One-dimensional cellular automata: Difference between revisions

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(One-dimensional cellular automata in BASIC256)
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It halts when a stable state has been reached:
It halts when a stable state has been reached:
<pre>00110000000000000000 9</pre>
<pre>00110000000000000000 9</pre>

=={{header|BASIC256}}==
<lang BASIC256>arraybase 1
dim start = {0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0}
dim sgtes(start[?]+1)

for k = 0 to 9
print "Generation "; k; ": ";
for j = 0 to start[?]-1

if start[j] then print "#"; else print "_";
if start[j-1] + start[j] + start[j+1] = 2 then sgtes[j] = 1 else sgtes[j] = 0
next j
print
for j = 0 to start[?]-1
start[j] = sgtes[j]
next j
next k</lang>


=={{header|Batch File}}==
=={{header|Batch File}}==

Revision as of 19:56, 15 June 2022

Task
One-dimensional cellular automata
You are encouraged to solve this task according to the task description, using any language you may know.

Assume an array of cells with an initial distribution of live and dead cells, and imaginary cells off the end of the array having fixed values.

Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation.

If, in the following table, a live cell is represented by 1 and a dead cell by 0 then to generate the value of the cell at a particular index in the array of cellular values you use the following table:

000 -> 0  # 
001 -> 0  #
010 -> 0  # Dies without enough neighbours
011 -> 1  # Needs one neighbour to survive
100 -> 0  #
101 -> 1  # Two neighbours giving birth
110 -> 1  # Needs one neighbour to survive
111 -> 0  # Starved to death.

11l

Translation of: Python

<lang 11l>V gen = ‘_###_##_#_#_#_#__#__’.map(ch -> Int(ch == ‘#’)) L(n) 10

  print(gen.map(cell -> (I cell != 0 {‘#’} E ‘_’)).join(‘’))
  gen = [0] [+] gen [+] [0]
  gen = (0 .< gen.len - 2).map(m -> Int(sum(:gen[m .+ 3]) == 2))</lang>
Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________

8th

<lang forth> \ one-dimensional automaton

\ direct map of input state to output state: {

 "   " : 32,
 "  #" : 32,
 " # " : 32,
 " ##" : 35,
 "#  " : 32,
 "# #" : 35,
 "## " : 35,
 "###" : 32,

} var, lifemap

transition \ s ix (r:s') -- (r:s')
   >r dup r@ n:1- 3 s:slice
   lifemap @ swap caseof
   r> swap r@ -rot s:! >r ;

\ run over 'state' and generate new state

gen \ s -- s'
 clone >r
 dup s:len 2 n:-
 ' transition 1 rot loop
 drop r> ;
life \ s -- s'
 dup . cr gen  ;

" ### ## # # # # # " ' life 10 times bye

</lang>

ACL2

<lang lisp>(defun rc-step-r (cells)

  (if (endp (rest cells))
      nil
      (cons (if (second cells)
                (xor (first cells) (third cells))
                (and (first cells) (third cells)))
            (rc-step-r (rest cells)))))

(defun rc-step (cells)

  (cons (and (first cells) (second cells))
        (rc-step-r cells)))

(defun rc-steps-r (cells n prev)

  (declare (xargs :measure (nfix n)))
  (if (or (zp n) (equal cells prev))
      nil
      (let ((new (rc-step cells)))
         (cons new (rc-steps-r new (1- n) cells)))))

(defun rc-steps (cells n)

 (cons cells (rc-steps-r cells n nil)))

(defun pretty-row (row)

  (if (endp row)
      (cw "~%")
      (prog2$ (cw (if (first row) "#" "-"))
              (pretty-row (rest row)))))

(defun pretty-output (out)

  (if (endp out)
      nil
      (prog2$ (pretty-row (first out))
              (pretty-output (rest out)))))</lang>

Action!

<lang Action!>CHAR FUNC CalcCell(CHAR prev,curr,next)

 IF prev='. AND curr='# AND next='# THEN
   RETURN ('#)
 ELSEIF prev='# AND curr='. AND next='# THEN
   RETURN ('#)
 ELSEIF prev='# AND curr='# AND next='. THEN
   RETURN ('#)
 FI

RETURN ('.)

PROC NextGeneration(CHAR ARRAY s)

 BYTE i
 CHAR prev,curr,next
 IF s(0)<4 THEN RETURN FI
 prev=s(1) curr=s(2) next=s(3)
 i=2
 DO
   s(i)=CalcCell(prev,curr,next)
   i==+1
   IF i=s(0) THEN EXIT FI
   prev=curr curr=next next=s(i+1)
 OD

RETURN

PROC Main()

 DEFINE MAXGEN="9"
 CHAR ARRAY s=".###.##.#.#.#.#..#.."
 BYTE i
 FOR i=0 TO MAXGEN
 DO
   PrintF("Generation %I: %S%E",i,s)
   IF i<MAXGEN THEN
     NextGeneration(s)
   FI
 OD

RETURN</lang>

Output:

Screenshot from Atari 8-bit computer

Generation 0: .###.##.#.#.#.#..#..
Generation 1: .#.#####.#.#.#......
Generation 2: ..##...##.#.#.......
Generation 3: ..##...###.#........
Generation 4: ..##...#.##.........
Generation 5: ..##....###.........
Generation 6: ..##....#.#.........
Generation 7: ..##.....#..........
Generation 8: ..##................
Generation 9: ..##................

Ada

<lang ada>with Ada.Text_IO; use Ada.Text_IO;

procedure Cellular_Automata is

  type Petri_Dish is array (Positive range <>) of Boolean;
  procedure Step (Culture : in out Petri_Dish) is
     Left  : Boolean := False;
     This  : Boolean;
     Right : Boolean;
  begin
     for Index in Culture'First..Culture'Last - 1 loop
        Right := Culture (Index + 1);
        This  := Culture (Index);
        Culture (Index) := (This and (Left xor Right)) or (not This and Left and Right);
        Left := This;
     end loop;
     Culture (Culture'Last) := Culture (Culture'Last) and not Left;
  end Step;
  
  procedure Put (Culture : Petri_Dish) is
  begin
     for Index in Culture'Range loop
        if Culture (Index) then
           Put ('#');
        else
           Put ('_');
        end if;
     end loop;
  end Put;
  Culture : Petri_Dish :=
     (  False, True, True,  True, False, True,  True, False, True, False, True,
        False, True, False, True, False, False, True, False, False
     );

begin

  for Generation in 0..9 loop
     Put ("Generation" & Integer'Image (Generation) & ' ');
     Put (Culture);
     New_Line;
     Step (Culture);
  end loop;

end Cellular_Automata;</lang>

The implementation defines Petri dish type with Boolean items identifying whether a place is occupied by a living cell. State transition is determined by a simple Boolean expression of three arguments.

Output:
Generation 0 _###_##_#_#_#_#__#__
Generation 1 _#_#####_#_#_#______
Generation 2 __##___##_#_#_______
Generation 3 __##___###_#________
Generation 4 __##___#_##_________
Generation 5 __##____###_________
Generation 6 __##____#_#_________
Generation 7 __##_____#__________
Generation 8 __##________________
Generation 9 __##________________

ALGOL 68

Using the low level packed arrays of BITS manipulation operators

Works with: ALGOL 68 version Revision 1 - no extensions to language used
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny

<lang algol68>INT stop generation = 9; INT universe width = 20; FORMAT alive or dead = $b("#","_")$;

BITS universe := 2r01110110101010100100;

  # universe := BIN ( ENTIER ( random * max int ) ); #

INT upb universe = bits width; INT lwb universe = bits width - universe width + 1;

PROC couple = (BITS parent, INT lwb, upb)BOOL: (

 SHORT INT sum := 0;
 FOR bit FROM lwb TO upb DO
   sum +:= ABS (bit ELEM parent)
 OD;
 sum = 2

);

FOR generation FROM 0 WHILE

 printf(($"Generation "d": "$, generation,
        $f(alive or dead)$, []BOOL(universe)[lwb universe:upb universe],
        $l$));
  1. WHILE # generation < stop generation DO
 BITS next universe := 2r0;  
 
 # process the first event horizon manually #
 IF couple(universe,lwb universe,lwb universe + 1) THEN 
   next universe := 2r10
 FI;
 
 # process the middle kingdom in a loop #
 FOR bit FROM lwb universe + 1 TO upb universe - 1 DO 
   IF couple(universe,bit-1,bit+1) THEN
     next universe := next universe OR 2r1
   FI;
   next universe := next universe SHL 1
 OD; 
 # process the last event horizon manually #
 IF couple(universe, upb universe - 1, upb universe) THEN 
   next universe := next universe OR 2r1
 FI;
 universe := next universe

OD</lang>

Output:
Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________

Using high level BOOL arrays

Works with: ALGOL 68 version Revision 1 - no extensions to language used
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny

<lang algol68>INT stop generation = 9; INT upb universe = 20; FORMAT alive or dead = $b("#","_")$;

BITS bits universe := 2r01110110101010100100;

  # bits universe := BIN ( ENTIER ( random * max int ) ); #

[upb universe] BOOL universe := []BOOL(bits universe)[bits width - upb universe + 1:];

PROC couple = (REF[]BOOL parent)BOOL: (

 SHORT INT sum := 0;
 FOR bit FROM LWB parent TO UPB parent DO
   sum +:= ABS (parent[bit])
 OD;
 sum = 2

);

FOR generation FROM 0 WHILE

 printf(($"Generation "d": "$, generation,
        $f(alive or dead)$, universe,
        $l$));
  1. WHILE # generation < stop generation DO
 [UPB universe]BOOL next universe;
 
 # process the first event horizon manually #
 next universe[1] := couple(universe[:2]);
 
 # process the middle kingdom in a loop #
 FOR bit FROM LWB universe + 1 TO UPB universe - 1 DO 
   next universe[bit] := couple(universe[bit-1:bit+1])
 OD; 
 # process the last event horizon manually #
 next universe[UPB universe] := couple(universe[UPB universe - 1: ]);
 universe := next universe

OD</lang>

Output:
Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________

ALGOL W

Using a string to represent the cells and stopping when the next state is th same as the previous one. <lang algolw>begin

   string(20) state;
   string(20) nextState;
   integer    generation;
   generation := 0;
   state := "_###_##_#_#_#_#__#__";
   while begin
       write( i_w := 1, s_w := 1, "Generation ", generation, state );
       nextState := "____________________";
       for cPos := 1 until 18 do begin
           string(3) curr;
           curr := state( cPos - 1 // 3 );
           nextState( cPos // 1 ) := if curr = "_##" or curr = "#_#" or curr = "##_" then "#" else "_"
       end for_cPos ;
       ( state not = nextState )
   end do begin
       state := nextState;
       generation := generation + 1
   end while_not_finished

end.</lang>

Output:
Generation 0 _###_##_#_#_#_#__#__
Generation 1 _#_#####_#_#_#______
Generation 2 __##___##_#_#_______
Generation 3 __##___###_#________
Generation 4 __##___#_##_________
Generation 5 __##____###_________
Generation 6 __##____#_#_________
Generation 7 __##_____#__________
Generation 8 __##________________

Arturo

<lang rebol>evolve: function [arr][

   ary: [0] ++ arr ++ [0]
   ret: new []
   loop 1..(size ary)-2 'i [
       a: ary\[i-1]
       b: ary\[i]
       c: ary\[i+1]
       if? 2 = a+b+c -> 'ret ++ 1
       else          -> 'ret ++ 0
   ]
   ret

]

printIt: function [arr][

   print replace replace join map arr => [to :string] "0" "_" "1" "#"

]

arr: [0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0] printIt arr

newGen: evolve arr while [newGen <> arr][

   arr: newGen
   newGen: evolve arr
   printIt newGen

]</lang>

Output:
_###_##_#_#_#_#__#__
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________

AutoHotkey

ahk discussion <lang autohotkey>n := 22, n1 := n+1, v0 := v%n1% := 0  ; set grid dimensions, and fixed cells

Loop % n {  ; draw a line of checkboxes

  v%A_Index% := 0
  Gui Add, CheckBox, % "y10 w17 h17 gCheck x" A_Index*17-5 " vv" A_Index

} Gui Add, Button, x+5 y6, step  ; button to step to next generation Gui Show Return

Check:

  GuiControlGet %A_GuiControl%             ; set cells by the mouse

Return

ButtonStep:  ; move to next generation

  Loop % n
     i := A_Index-1, j := i+2, w%A_Index% := v%i%+v%A_Index%+v%j% = 2
  Loop % n
     GuiControl,,v%A_Index%, % v%A_Index% := w%A_Index%

Return

GuiClose:  ; exit when GUI is closed ExitApp</lang>

AWK

<lang awk>#!/usr/bin/awk -f BEGIN {

   edge = 1
   ruleNum = 104 # 01101000
   maxGen = 9
   mark = "@"
   space = "."
   initialState = ".@@@.@@.@.@.@.@..@.."
   width = length(initialState)
   delete rules
   delete state
   
   initRules(ruleNum)
   initState(initialState, mark)
   for (g = 0; g < maxGen; g++) {
       showState(g, mark, space)
       nextState()
   }
   showState(g, mark, space)

}

function nextState( newState, i, n) {

   delete newState
   for (i = 1; i < width - 1; i++) {
       n = getRuleNum(i)
       newState[i] = rules[n]
   }
   for (i = 0; i < width; i++) { # copy, can't assign arrays
       state[i] = newState[i]
   }

}

  1. Convert a three cell neighborhood from binary to decimal

function getRuleNum(i, rn, j, p) {

   rn = 0
   for (j = -1; j < 2; j++) {
       p = i + j
       rn = rn * 2 + (p < 0 || p > width ? edge : state[p])
   }
   return rn

}

function showState(gen, mark, space, i) {

   printf("%3d: ", gen)
   for (i = 1; i <= width; i++) {
       printf(" %s", (state[i] ? mark : space))
   }
   print ""

}

  1. Make state transition lookup table from rule number.

function initRules(ruleNum, i, r) {

   delete rules;
   r = ruleNum
   for (i = 0; i < 8; i++) {
       rules[i] = r % 2
       r = int(r / 2)
   }

}

function initState(init, mark, i) {

   delete state
   srand()
   for (i = 0; i < width; i++) {
       state[i] = (substr(init, i, 1) == mark ? 1 : 0) # Given an initial string.
       # state[int(width/2)] = '@'  # middle cell
       # state[i] = int(rand() * 100) < 30 ? 1 : 0 # 30% of cells
   }

} </lang>

Output:
  0:  . @ @ @ . @ @ . @ . @ . @ . @ . . @ . .
  1:  . @ . @ @ @ @ @ . @ . @ . @ . . . . . .
  2:  . . @ @ . . . @ @ . @ . @ . . . . . . .
  3:  . . @ @ . . . @ @ @ . @ . . . . . . . .
  4:  . . @ @ . . . @ . @ @ . . . . . . . . .
  5:  . . @ @ . . . . @ @ @ . . . . . . . . .
  6:  . . @ @ . . . . @ . @ . . . . . . . . .
  7:  . . @ @ . . . . . @ . . . . . . . . . .
  8:  . . @ @ . . . . . . . . . . . . . . . .
  9:  . . @ @ . . . . . . . . . . . . . . . .

<lang awk>Another new solution (twice size as previous solution) : cat automata.awk :

  1. !/usr/local/bin/gawk -f
  1. User defined functions

function ASCII_to_Binary(str_) { gsub("_","0",str_); gsub("@","1",str_) return str_ }

function Binary_to_ASCII(bit_) { gsub("0","_",bit_); gsub("1","@",bit_) return bit_ }

function automate(b1,b2,b3) { a = and(b1,b2,b3) b = or(b1,b2,b3) c = xor(b1,b2,b3) d = a + b + c return d == 1 ? 1 : 0 }

  1. For each line in input do

{ str_ = $0 gen = 0 taille = length(str_) print "0: " str_ do { gen ? str_previous = str_ : str_previous = "" gen += 1 str_ = ASCII_to_Binary(str_) split(str_,tab,"") str_ = and(tab[1],tab[2]) for (i=1; i<=taille-2; i++) { str_ = str_ automate(tab[i],tab[i+1],tab[i+2]) } str_ = str_ and(tab[taille-1],tab[taille]) print gen ": " Binary_to_ASCII(str_)

  } while (str_ != str_previous)

} </lang>

Output:
$ echo ".@@@.@@.@.@.@.@..@.." | awk -f automata.awk
0: .@@@.@@.@.@.@.@..@..
1: _@_@@@@@_@_@_@______
2: __@@___@@_@_@_______
3: __@@___@@@_@________
4: __@@___@_@@_________
5: __@@____@@@_________
6: __@@____@_@_________
7: __@@_____@__________
8: __@@________________
9: __@@________________

BASIC

Works with: QBasic version 1.1
Works with: QuickBasic version 4.5
Translation of: Java

<lang qbasic>DECLARE FUNCTION life$ (lastGen$) DECLARE FUNCTION getNeighbors! (group$) CLS start$ = "_###_##_#_#_#_#__#__" numGens = 10 FOR i = 0 TO numGens - 1 PRINT "Generation"; i; ": "; start$ start$ = life$(start$) NEXT i

FUNCTION getNeighbors (group$) ans = 0 IF (MID$(group$, 1, 1) = "#") THEN ans = ans + 1 IF (MID$(group$, 3, 1) = "#") THEN ans = ans + 1 getNeighbors = ans END FUNCTION

FUNCTION life$ (lastGen$) newGen$ = "" FOR i = 1 TO LEN(lastGen$) neighbors = 0 IF (i = 1) THEN 'left edge IF MID$(lastGen$, 2, 1) = "#" THEN neighbors = 1 ELSE neighbors = 0 END IF ELSEIF (i = LEN(lastGen$)) THEN 'right edge IF MID$(lastGen$, LEN(lastGen$) - 1, 1) = "#" THEN neighbors = 1 ELSE neighbors = 0 END IF ELSE 'middle neighbors = getNeighbors(MID$(lastGen$, i - 1, 3)) END IF

IF (neighbors = 0) THEN 'dies or stays dead with no neighbors newGen$ = newGen$ + "_" END IF IF (neighbors = 1) THEN 'stays with one neighbor newGen$ = newGen$ + MID$(lastGen$, i, 1) END IF IF (neighbors = 2) THEN 'flips with two neighbors IF MID$(lastGen$, i, 1) = "#" THEN newGen$ = newGen$ + "_" ELSE newGen$ = newGen$ + "#" END IF END IF NEXT i life$ = newGen$ END FUNCTION</lang>

Output:
Generation 0 : _###_##_#_#_#_#__#__
Generation 1 : _#_#####_#_#_#______
Generation 2 : __##___##_#_#_______
Generation 3 : __##___###_#________
Generation 4 : __##___#_##_________
Generation 5 : __##____###_________
Generation 6 : __##____#_#_________
Generation 7 : __##_____#__________
Generation 8 : __##________________
Generation 9 : __##________________

FreeBASIC

<lang freebasic>#define SIZE 640

randomize timer

dim as ubyte arr(0 to SIZE-1, 0 to 1) dim as uinteger i for i = 0 to SIZE - 1 'initialise array with zeroes and ones

   arr(i, 0)=int(rnd+0.5)

next i

screen 12 'display graphically

dim as string ch=" " dim as uinteger j = 0, cur = 0, nxt, prv, neigh while not ch = "q" or ch = "Q"

   for i = 0 to SIZE - 1
       pset(i, j), 8+7*arr(i,cur)   'print off cells as grey, on cells as bright white
       nxt = (i + 1) mod SIZE
       prv = (i - 1)
       if prv < 0 then prv = SIZE - 1   'let's have a wrap-around array for fun
       neigh = arr(prv, cur) + arr(nxt, cur)
       if arr(i, cur) = 0 then    'evolution rules
           if neigh = 2 then
               arr(i, 1-cur) = 1
           else
               arr(i, 1-cur) = 0
           end if
       else
           if neigh = 0 or neigh = 2 then
               arr(i, 1-cur) = 0
           else
               arr(i, 1-cur) = 1
           end if
       end if
   next i
   j = j + 1
   cur = 1 - cur
   do
       ch = inkey
       if ch <> "" then exit do   'press any key to advance the sim
                                  'or Q to exit
   loop

wend</lang>

Sinclair ZX81 BASIC

Works with the unexpanded (1k RAM) ZX81. <lang basic> 10 LET N$="01110110101010100100"

20 LET G=1
30 PRINT N$
40 LET O$=N$
50 LET N$=""
60 PRINT AT 0,28;G
70 LET N=0
80 FOR I=1 TO LEN O$
90 IF I=1 THEN GOTO 120

100 LET N=VAL O$(I-1) 110 IF I=LEN O$ THEN GOTO 130 120 LET N=N+VAL O$(I+1) 130 IF N=0 THEN LET N$=N$+"0" 140 IF N=1 THEN LET N$=N$+O$(I) 150 IF N=2 THEN LET N$=N$+STR$ NOT VAL O$(I) 160 PRINT AT 0,I-1;N$(I) 170 NEXT I 180 LET G=G+1 190 IF N$<>O$ THEN GOTO 40</lang>

Output:

The program overwrites each cell on the screen as it updates it (which it does quite slowly—there is no difficulty about watching what it is doing), with a counter to the right showing the generation it is currently working on. When it is part of the way through, for example, the display looks like this:

00110001011000000000        5

It halts when a stable state has been reached:

00110000000000000000        9

BASIC256

<lang BASIC256>arraybase 1 dim start = {0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0} dim sgtes(start[?]+1)

for k = 0 to 9

   print "Generation "; k; ": ";
   for j = 0 to start[?]-1
       if start[j] then print "#"; else print "_";
       if start[j-1] + start[j] + start[j+1] = 2 then sgtes[j] = 1 else sgtes[j] = 0
   next j
   print
   for j = 0 to start[?]-1
       start[j] = sgtes[j]
   next j

next k</lang>

Batch File

This implementation will not stop showing generations, unless the cellular automata is already stable. <lang dos>@echo off setlocal enabledelayedexpansion

THE MAIN THING

call :one-dca __###__##_#_##_###__######_###_#####_#__##_____#_#_#######__ pause>nul exit /b

/THE MAIN THING
THE PROCESSOR
one-dca

echo.&set numchars=0&set proc=%1

COUNT THE NUMBER OF CHARS

set bef=%proc:_=_,% set bef=%bef:#=#,% set bef=%bef:~0,-1% for %%x in (%bef%) do set /a numchars+=1

set /a endchar=%numchars%-1

nextgen

echo. ^| %proc% ^| set currnum=0 set newgen=

editeachchar

set neigh=0 set /a testnum2=%currnum%+1 set /a testnum1=%currnum%-1 if %currnum%==%endchar% ( set testchar=!proc:~%testnum1%,1! if !testchar!==# (set neigh=1) ) else ( if %currnum%==0 ( set testchar=%proc:~1,1% if !testchar!==# (set neigh=1) ) else ( set testchar1=!proc:~%testnum1%,1! set testchar2=!proc:~%testnum2%,1! if !testchar1!==# (set /a neigh+=1) if !testchar2!==# (set /a neigh+=1) ) ) if %neigh%==0 (set newgen=%newgen%_) if %neigh%==1 ( set testchar=!proc:~%currnum%,1! set newgen=%newgen%!testchar! ) if %neigh%==2 ( set testchar=!proc:~%currnum%,1! if !testchar!==# (set newgen=%newgen%_) else (set newgen=%newgen%#) ) if %currnum%==%endchar% (goto :cond) else (set /a currnum+=1&goto :editeachchar)

cond

if %proc%==%newgen% (echo.&echo ...The sample is now stable.&goto :EOF) set proc=%newgen% goto :nextgen

/THE (LLLLLLOOOOOOOOOOOOONNNNNNNNGGGGGG.....) PROCESSOR</lang>
Output:
   | __###__##_#_##_###__######_###_#####_#__##_____#_#_#######__ |
   | __#_#__###_#####_#__#____###_###___##___##______#_##_____#__ |
   | ___#___#_###___##________#_###_#___##___##_______###________ |
   | ________##_#___##_________##_##____##___##_______#_#________ |
   | ________###____##_________#####____##___##________#_________ |
   | ________#_#____##_________#___#____##___##__________________ |
   | _________#_____##__________________##___##__________________ |
   | _______________##__________________##___##__________________ |

         ...The sample is now stable.

BBC BASIC

<lang bbcbasic> DIM rule$(7)

     rule$() = "0", "0", "0", "1", "0", "1", "1", "0"
     
     now$ = "01110110101010100100"
     
     FOR generation% = 0 TO 9
       PRINT "Generation " ; generation% ":", now$
       next$ = ""
       FOR cell% = 1 TO LEN(now$)
         next$ += rule$(EVAL("%"+MID$("0"+now$+"0", cell%, 3)))
       NEXT cell%
       SWAP now$, next$
     NEXT generation%</lang>
Output:
Generation 0:       01110110101010100100
Generation 1:       01011111010101000000
Generation 2:       00110001101010000000
Generation 3:       00110001110100000000
Generation 4:       00110001011000000000
Generation 5:       00110000111000000000
Generation 6:       00110000101000000000
Generation 7:       00110000010000000000
Generation 8:       00110000000000000000
Generation 9:       00110000000000000000

Befunge

<lang befunge>v

" !!! !! ! ! ! !  !  "                                                          ,*25                    <v
"                    "                                                           ,*25,,,,,,,,,,,,,,,,,,,,<v
"                    "                                                            ,*25,,,,,,,,,,,,,,,,,,,,<v
"                    "                                                             ,*25,,,,,,,,,,,,,,,,,,,,<v
"                    "                                                              ,*25,,,,,,,,,,,,,,,,,,,,<v
"                    "                                                               ,*25,,,,,,,,,,,,,,,,,,,,<v
"                    "                                                                ,*25,,,,,,,,,,,,,,,,,,,,<v
"                    "                                                                 ,*25,,,,,,,,,,,,,,,,,,,,<v
"                    "                                                                  ,*25,,,,,,,,,,,,,,,,,,,,<v
                                                                     v$<                @,*25,,,,,,,,,,,,,,,,,,,,<

>110p3>:1-10gg" "-4* \:10gg" "-2* \:1+10gg" "-\:54*1+`#v_20p++ :2`#v_ >:4`#v_> >$" "v

                                                                  >:3`#^_v>:6`|                          
     ^                                                >$$$$320p10g1+:9`v >    >$"!"> 20g10g1+p 20g1+:20p 
     ^                                                                v_10p10g                           
                                                                      >                                 ^</lang>

Bracmat

<lang bracmat> ( ( evolve

   =   n z
     .   @( !arg
          : %?n ? @?z
          :   ?
              ( (   ( 000
                    | 001
                    | 010
                    | 100
                    | 111
                    )
                  & 0 !n:?n
                |   (011|101|110)
                  & 1 !n:?n
                )
              & ~`
              )
              ?
          )
       | rev$(str$(!z !n))
   )
 & 11101101010101001001:?S
 & :?seen
 &   whl
   ' ( ~(!seen:? !S ?)
     & out$!S
     & !S !seen:?seen
     & evolve$!S:?S
     )
 );</lang>
Output:
11101101010101001001
10111110101010000001
11100011010100000001
10100011101000000001
11000010110000000001
11000001110000000001
11000001010000000001
11000000100000000001
11000000000000000001

C

<lang c>#include <stdio.h>

  1. include <string.h>

char trans[] = "___#_##_";

  1. define v(i) (cell[i] != '_')

int evolve(char cell[], char backup[], int len) { int i, diff = 0;

for (i = 0; i < len; i++) { /* use left, self, right as binary number bits for table index */ backup[i] = trans[ v(i-1) * 4 + v(i) * 2 + v(i + 1) ]; diff += (backup[i] != cell[i]); }

strcpy(cell, backup); return diff; }

int main() { char c[] = "_###_##_#_#_#_#__#__\n", b[] = "____________________\n";

do { printf(c + 1); } while (evolve(c + 1, b + 1, sizeof(c) - 3)); return 0; }</lang>

Output:
###_##_#_#_#_#__#__
#_#####_#_#_#______
_##___##_#_#_______
_##___###_#________
_##___#_##_________
_##____###_________
_##____#_#_________
_##_____#__________
_##________________

Similar to above, but without a backup string: <lang c>#include <stdio.h>

char trans[] = "___#_##_";

int evolve(char c[], int len) { int i, diff = 0;

  1. define v(i) ((c[i] & 15) == 1)
  2. define each for (i = 0; i < len; i++)

each c[i] = (c[i] == '#'); each c[i] |= (trans[(v(i-1)*4 + v(i)*2 + v(i+1))] == '#') << 4; each diff += (c[i] & 0xf) ^ (c[i] >> 4); each c[i] = (c[i] >> 4) ? '#' : '_';

  1. undef each
  2. undef v

return diff; }

int main() { char c[] = "_###_##_#_#_#_#__#__\n";

do { printf(c + 1); } while (evolve(c + 1, sizeof(c) - 3)); return 0; }</lang>

C#

<lang csharp>using System; using System.Collections.Generic;

namespace prog { class MainClass { const int n_iter = 10; static int[] f = { 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0 };

public static void Main (string[] args) { for( int i=0; i<f.Length; i++ ) Console.Write( f[i]==0 ? "-" : "#" ); Console.WriteLine("");

int[] g = new int[f.Length]; for( int n=n_iter; n!=0; n-- ) { for( int i=1; i<f.Length-1; i++ ) { if ( (f[i-1] ^ f[i+1]) == 1 ) g[i] = f[i]; else if ( f[i] == 0 && (f[i-1] & f[i+1]) == 1 ) g[i] = 1; else g[i] = 0; } g[0] = ( (f[0] & f[1]) == 1 ) ? 1 : 0; g[g.Length-1] = ( (f[f.Length-1] & f[f.Length-2]) == 1 ) ? 1 : 0;

int[] tmp = f; f = g; g = tmp;

for( int i=0; i<f.Length; i++ ) Console.Write( f[i]==0 ? "-" : "#" ); Console.WriteLine(""); } } } }</lang>

C++

Uses std::bitset for efficient packing of bit values. <lang Cpp>#include <iostream>

  1. include <bitset>
  2. include <string>

const int ArraySize = 20; const int NumGenerations = 10; const std::string Initial = "0011101101010101001000";

int main() {

   // + 2 for the fixed ends of the array
   std::bitset<ArraySize + 2> array(Initial);
   for(int j = 0; j < NumGenerations; ++j)
   {
       std::bitset<ArraySize + 2> tmpArray(array);
       for(int i = ArraySize; i >= 1 ; --i)
       {
           if(array[i])
               std::cout << "#";
           else
               std::cout << "_";
           int val = (int)array[i-1] << 2 | (int)array[i] << 1 | (int)array[i+1];
           tmpArray[i] = (val == 3 || val == 5 || val == 6);
       }
       array = tmpArray;
       std::cout << std::endl;
   }

}</lang>

Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________

Ceylon

<lang ceylon>shared abstract class Cell(character) of alive | dead { shared Character character; string => character.string; shared formal Cell opposite; }

shared object alive extends Cell('#') { opposite => dead; } shared object dead extends Cell('_') { opposite => alive; }

shared Map<Character, Cell> cellsByCharacter = map { for (cell in `Cell`.caseValues) cell.character->cell };

shared class Automata1D({Cell*} initialCells) {


value permanentFirstCell = initialCells.first else dead; value permanentLastCell = initialCells.last else dead;

value cells = Array { *initialCells.rest.exceptLast };

shared Boolean evolve() {

value newCells = Array { for (index->cell in cells.indexed) let (left = cells[index - 1] else permanentFirstCell, right = cells[index + 1] else permanentLastCell, neighbours = [left, right], bothAlive = neighbours.every(alive.equals), bothDead = neighbours.every(dead.equals)) if (bothAlive) then cell.opposite else if (cell == alive && bothDead) then dead else cell };

if (newCells == cells) { return false; }

newCells.copyTo(cells); return true; }

string => permanentFirstCell.string + "".join(cells) + permanentLastCell.string; }

shared Automata1D? automata1d(String string) => let (cells = string.map((Character element) => cellsByCharacter[element])) if (cells.every((Cell? element) => element exists)) then Automata1D(cells.coalesced) else null;

shared void run() {

assert (exists automata = automata1d("__###__##_#_##_###__######_###_#####_#__##_____#_#_#######__"));

variable value generation = 0; print("generation ``generation`` ``automata``"); while (automata.evolve() && generation<10) { print("generation `` ++generation `` ``automata``"); } }</lang>

Clojure

<lang clojure>(ns one-dimensional-cellular-automata

 (:require (clojure.contrib (string :as s))))

(defn next-gen [cells]

 (loop [cs cells ncs (s/take 1 cells)]
   (let [f3 (s/take 3 cs)]
     (if (= 3 (count f3))
       (recur (s/drop 1 cs)
              (str ncs (if (= 2 (count (filter #(= \# %) f3))) "#" "_")))
       (str ncs (s/drop 1 cs))))))

(defn generate [n cells]

 (if (= n 0)
   '()
   (cons cells (generate (dec n) (next-gen cells)))))

</lang> <lang clojure>one-dimensional-cellular-automata> (doseq [cells (generate 9 "_###_##_#_#_#_#__#__")]

 (println cells))

_###_##_#_#_#_#__#__ _#_#####_#_#_#______ __##___##_#_#_______ __##___###_#________ __##___#_##_________ __##____###_________ __##____#_#_________ __##_____#__________ __##________________ nil </lang>

Another way:

<lang clojure>#!/usr/bin/env lein-exec

(require '[clojure.string :as str])

(def first-genr "_###_##_#_#_#_#__#__")

(def hospitable #{"_##"

                 "##_"
                 "#_#"})

(defn compute-next-genr

 [genr]
 (let [genr      (str "_" genr "_")
       groups    (map str/join (partition 3 1 genr))
       next-genr (for [g groups]
                   (if (hospitable g) \# \_))]
   (str/join next-genr)))
---------------- main -----------------

(loop [g first-genr

      i  0]
 (if (not= i 10)
   (do (println g)
       (recur (compute-next-genr g)
              (inc i)))))</lang>

Yet another way, easier to understand

<lang clojure> (def rules

{
   [0 0 0] 0
   [0 0 1] 0
   [0 1 0] 0
   [0 1 1] 1
   [1 0 0] 0
   [1 0 1] 1
   [1 1 0] 1
   [1 1 1] 0
 })

(defn nextgen [gen]

 (concat [0] 
         (->> gen
              (partition 3 1)
              (map vec)
              (map rules))
         [0]))
Output time!

(doseq [g (take 10 (iterate nextgen [0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0]))]

 (println g))

</lang>

COBOL

<lang cobol>

Identification division.                                        
Program-id. rc-1d-cell.                                         

Data division.                                                  
Working-storage section.                                        

  • > "Constants."
01 max-gens            pic  999  value   9.                     
01 state-width         pic   99  value  20.                     
01 state-table-init    pic x(20) value ".@@@.@@.@.@.@.@..@..".  
01 alive               pic    x  value "@".                     
01 dead                pic    x  value ".".                     

  • > The current state.
01 state-gen           pic  999  value   0.                     
01 state-row.                                                  
   05 state-row-gen   pic zz9.                                
   05 filler          pic  xx   value ": ".                   
   05 state-table.                                            
       10 state-cells pic   x   occurs 20 times.              

  • > The new state.
01 new-state-table.                                            
   05 new-state-cells pic   x   occurs 20 times.              

  • > Pointer into cell table during generational production.
01 cell-index          pic   99.                               
   88 at-beginning    value  1.                               
   88 is-inside       values 2 thru 19.                       
   88 at-end          value 20.                               

  • > The cell's neighborhood.
01 neighbor-count-def.                          
  03 neighbor-count      pic   9.
    88 is-comfy        value 1.                    
    88 is-ripe         value 2.                    

Procedure division.                                
    Perform Init-state-table.                      
    Perform max-gens times                         
        perform Display-row                        
        perform Next-state                         
    end-perform.                                   
    Perform Display-row.                           
    Stop run.                                      

Display-row.                                       
    Move state-gen to state-row-gen.     
    Display state-row.                   

  • > Determine who lives and who dies.
Next-state.                              
    Add 1 to state-gen.                  
    Move state-table to new-state-table. 

    Perform with test after              
        varying cell-index from 1 by 1   
        until at-end                     
        perform Count-neighbors          
        perform Die-off                             
        perform New-births                          
    end-perform                                     

    move new-state-table to state-table.            

  • > Living cell with wrong number of neighbors...
Die-off.                                            
    if state-cells(cell-index) =                    
    alive and not is-comfy    
        then move dead to new-state-cells(cell-index)           
    end-if                                                      
    .                                                           

  • > Empty cell with exactly two neighbors are...
New-births.                                                     
    if state-cells(cell-index) = dead and is-ripe
        then move alive to new-state-cells(cell-index)          
    end-if                                                      
   .                                                           
  • > How many living neighbors does a cell have?
Count-neighbors.                                                
    Move 0 to neighbor-count                        
    if at-beginning or at-end then                              
        add 1 to neighbor-count                      
    else                                                        
      if is-inside and state-cells(cell-index - 1) = alive        
      then                                                        
          add 1 to neighbor-count                     
      end-if                                                      
      if is-inside and state-cells(cell-index + 1) = alive        
      then                                                        
          add 1 to neighbor-count                     
      end-if                                                       
    end-if                                                        
    .                                                             

  • > String is easier to enter, but table is easier to work with,
  • > so move each character of the initialization string to the
  • > state table.
Init-state-table.                                                 
    Perform with test after                    
        varying cell-index from 1 by 1         
        until at-end                           
        move state-table-init(cell-index:1)    
          to state-cells(cell-index)           
     end-perform
     .                                                                             

</lang>

Output:
  0: .@@@.@@.@.@.@.@..@..
  1: .@.@@@@@.@.@.@......
  2: ..@@...@@.@.@.......
  3: ..@@...@@@.@........
  4: ..@@...@.@@.........
  5: ..@@....@@@.........
  6: ..@@....@.@.........
  7: ..@@.....@..........
  8: ..@@................
  9: ..@@................

=pre>###_##_#_#_#_#__#__

  1. _#####_#_#_#______

_##___##_#_#_______ _##___###_#________ _##___#_##_________ _##____###_________ _##____#_#_________ _##_____#__________ _##________________=CoffeeScript== <lang coffeescript>

  1. We could cheat and count the bits, but let's keep this general.
  2. . = dead, # = alive, middle cells survives iff one of the configurations
  3. below is satisified.

survival_scenarios = [

 '.##' # happy neighbors
 '#.#' # birth
 '##.' # happy neighbors

]

b2c = (b) -> if b then '#' else '.'

cell_next_gen = (left_alive, me_alive, right_alive) ->

 fingerprint = b2c(left_alive) + b2c(me_alive) + b2c(right_alive)
 fingerprint in survival_scenarios
 

cells_for_next_gen = (cells) ->

 # This function assumes a finite array, i.e. cells can't be born outside
 # the original array.
 (cell_next_gen(cells[i-1], cells[i], cells[i+1]) for i in [0...cells.length])
 

display = (cells) ->

 (b2c(is_alive) for is_alive in cells).join 
   

simulate = (cells) ->

 while true
   console.log display cells
   new_cells = cells_for_next_gen cells
   break if display(cells) == display(new_cells)
   cells = new_cells
 console.log "equilibrium achieved"
   

simulate (c == '#' for c in ".###.##.#.#.#.#..#..") </lang>

Output:
> coffee cellular_automata.coffee 
.###.##.#.#.#.#..#..
.#.#####.#.#.#......
..##...##.#.#.......
..##...###.#........
..##...#.##.........
..##....###.........
..##....#.#.........
..##.....#..........
..##................
equilibrium achieved

Common Lisp

Based upon the Ruby version. <lang lisp>(defun value (x)

 (assert (> (length x) 1))
 (coerce x 'simple-bit-vector))

(defun count-neighbors-and-self (value i)

 (flet ((ref (i)
          (if (array-in-bounds-p value i)
              (bit value i)
              0)))
   (declare (inline ref))
   (+ (ref (1- i))
      (ref i)
      (ref (1+ i)))))

(defun next-cycle (value)

 (let ((new-value (make-array (length value) :element-type 'bit)))
   (loop for i below (length value)
         do (setf (bit new-value i)
                  (if (= 2 (count-neighbors-and-self value i))
                      1
                      0)))
   new-value))

(defun print-world (value &optional (stream *standard-output*))

 (loop for i below (length value)
       do (princ (if (zerop (bit value i)) #\. #\#)
                 stream))
 (terpri stream))</lang>

<lang lisp>CL-USER> (loop for previous-value = nil then value

              for value = #*01110110101010100100 then (next-cycle value)
              until (equalp value previous-value)
              do (print-world value))

.###.##.#.#.#.#..#.. .#.#####.#.#.#...... ..##...##.#.#....... ..##...###.#........ ..##...#.##......... ..##....###......... ..##....#.#......... ..##.....#.......... ..##................</lang>

D

<lang d>void main() {

  import std.stdio, std.algorithm;
  enum nGenerations = 10;
  enum initial = "0011101101010101001000";
  enum table = "00010110";
  char[initial.length + 2] A = '0', B = '0';
  A[1 .. $-1] = initial;
  foreach (immutable _; 0 .. nGenerations) {
     foreach (immutable i; 1 .. A.length - 1) {
        write(A[i] == '0' ? '_' : '#');
        const val = (A[i-1]-'0' << 2) | (A[i]-'0' << 1) | (A[i+1]-'0');
        B[i] = table[val];
     }
     A.swap(B);
     writeln;
  }

}</lang>

Output:
__###_##_#_#_#_#__#___
__#_#####_#_#_#_______
___##___##_#_#________
___##___###_#_________
___##___#_##__________
___##____###__________
___##____#_#__________
___##_____#___________
___##_________________
___##_________________

Alternative Version

Translation of: Raku

<lang d>void main() {

   import std.stdio, std.algorithm, std.range;
   auto A = "_###_##_#_#_#_#__#__".map!q{a == '#'}.array;
   auto B = A.dup;
   do {
       A.map!q{ "_#"[a] }.writeln;
       A.zip(A.cycle.drop(1), A.cycle.drop(A.length - 1))
       .map!(t => [t[]].sum == 2).copy(B);
       A.swap(B);
   } while (A != B);

}</lang>

Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________

Alternative Version II

This version saves memory representing the state in an array of bits. For a higher performance a SWAR approach should be tried.

Translation of: C++

<lang d>void main() {

   import std.stdio, std.algorithm, std.range, std.bitmanip;
   immutable initial = "__###_##_#_#_#_#__#___";
   enum nGenerations = 10;
   BitArray A, B;
   A.init(initial.map!(c => c == '#').array);
   B.length = initial.length;
   foreach (immutable _; 0 .. nGenerations) {
       //A.map!(b => b ? '#' : '_').writeln;
       //foreach (immutable i, immutable b; A) {
       foreach (immutable i; 1 .. A.length - 1) {
           "_#"[A[i]].write;
           immutable val = (uint(A[i - 1]) << 2) |
                           (uint(A[i])     << 1) |
                            uint(A[i + 1]);
           B[i] = val == 3 || val == 5 || val == 6;
       }
       writeln;
       A.swap(B);
   }

}</lang> The output is the same as the second version.

DWScript

<lang delphi>const ngenerations = 10; const table = [0, 0, 0, 1, 0, 1, 1, 0];

var a := [0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0]; var b := a;

var i, j : Integer; for i := 1 to ngenerations do begin

  for j := a.low+1 to a.high-1 do begin
     if a[j] = 0 then
        Print('_')
     else Print('#');
     var val := (a[j-1] shl 2) or (a[j] shl 1) or a[j+1];
     b[j] := table[val];
  end;
  var tmp := a;
  a := b;
  b := tmp;
  PrintLn();

end; </lang>

Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________

Déjà Vu

<lang dejavu>new-state size: 0 ] repeat size: random-range 0 2 [ 0

update s1 s2: for i range 1 - len s1 2: s1! -- i s1! i s1! ++ i + + set-to s2 i = 2 s2 s1

print-state s: for i range 1 - len s 2: !print\ s! i !print ""

same-state s1 s2: for i range 1 - len s1 2: if /= s1! i s2! i: return false true

run size: new-state size new-state size while true: update print-state over if same-state over over: return print-state drop

run 60</lang>

Output:
001110011010110111001111110111011111010011000001010111111100
001010011101111101001000011101110001100011000000101100000100
000100010111000110000000010111010001100011000000011100000000
000000001101000110000000001101100001100011000000010100000000
000000001110000110000000001111100001100011000000001000000000
000000001010000110000000001000100001100011000000000000000000
000000000100000110000000000000000001100011000000000000000000
000000000000000110000000000000000001100011000000000000000000
000000000000000110000000000000000001100011000000000000000000

E

<lang e>def step(state, rule) {

   var result := state(0, 1) # fixed left cell
   for i in 1..(state.size() - 2) {
       # Rule function receives the substring which is the neighborhood
       result += E.toString(rule(state(i-1, i+2)))
   }
   result += state(state.size() - 1) # fixed right cell
   return result

}

def play(var state, rule, count, out) {

   out.print(`0 | $state$\n`)
   for i in 1..count {
       state := step(state, rosettaRule)
       out.print(`$i | $state$\n`)
   }
   return state

}</lang>

<lang e>def rosettaRule := [

   "   " => " ",
   "  #" => " ",
   " # " => " ",
   " ##" => "#",
   "#  " => " ",
   "# #" => "#",
   "## " => "#",
   "###" => " ",

].get

? play(" ### ## # # # # # ", rosettaRule, 9, stdout) 0 | ### ## # # # # # 1 | # ##### # # # 2 | ## ## # # 3 | ## ### # 4 | ## # ## 5 | ## ### 6 | ## # # 7 | ## # 8 | ## 9 | ##

  1. value: " ## "</lang>

Eiffel

<lang Eiffel> class APPLICATION

create make

feature

make -- First 10 states of the cellular automata. local r: RANDOM automata: STRING do create r.make create automata.make_empty across 1 |..| 10 as c loop if r.double_item < 0.5 then automata.append ("0") else automata.append ("1") end r.forth end across 1 |..| 10 as c loop io.put_string (automata + "%N") automata := update (automata) end end

update (s: STRING): STRING -- Next state of the cellular automata 's'. require enough_states: s.count > 1 local i: INTEGER do create Result.make_empty -- Dealing with the left border. if s [1] = '1' and s [2] = '1' then Result.append ("1") else Result.append ("0") end -- Dealing with the middle cells. from i := 2 until i = s.count loop if (s [i] = '0' and (s [i - 1] = '0' or (s [i - 1] = '1' and s [i + 1] = '0'))) or ((s [i] = '1') and ((s [i - 1] = '1' and s [i + 1] = '1') or (s [i - 1] = '0' and s [i + 1] = '0'))) then Result.append ("0") else Result.append ("1") end i := i + 1 end -- Dealing with the right border. if s [s.count] = '1' and s [s.count - 1] = '1' then Result.append ("1") else Result.append ("0") end ensure has_same_length: s.count = Result.count end

end </lang>

Output:
1011101110
0110111010
0111101100
0100111100
0000100100
0000000000
0000000000
0000000000
0000000000
0000000000

Elixir

Translation of: Ruby

<lang elixir>defmodule RC do

 def run(list, gen \\ 0) do
   print(list, gen)
   next = evolve(list)
   if next == list, do: print(next, gen+1), else: run(next, gen+1)
 end
 
 defp evolve(list), do: evolve(Enum.concat([[0], list, [0]]), [])
 
 defp evolve([a,b,c],      next), do: Enum.reverse([life(a,b,c) | next])
 defp evolve([a,b,c|rest], next), do: evolve([b,c|rest], [life(a,b,c) | next])
 
 defp life(a,b,c), do: (if a+b+c == 2, do: 1, else: 0)
 
 defp print(list, gen) do
   str = "Generation #{gen}: "
   IO.puts Enum.reduce(list, str, fn x,s -> s <> if x==0, do: ".", else: "#" end)
 end

end

RC.run([0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0])</lang>

Output:
Generation 0: .###.##.#.#.#.#..#..
Generation 1: .#.#####.#.#.#......
Generation 2: ..##...##.#.#.......
Generation 3: ..##...###.#........
Generation 4: ..##...#.##.........
Generation 5: ..##....###.........
Generation 6: ..##....#.#.........
Generation 7: ..##.....#..........
Generation 8: ..##................
Generation 9: ..##................

Elm

<lang elm>import Maybe exposing (withDefault) import List exposing (length, tail, reverse, concat, head, append, map3) import Html exposing (Html, div, h1, text) import String exposing (join) import Svg exposing (svg) import Svg.Attributes exposing (version, width, height, viewBox,cx,cy, fill, r) import Html.App exposing (program) import Random exposing (step, initialSeed, bool, list) import Matrix exposing (fromList, mapWithLocation, flatten) -- chendrix/elm-matrix import Time exposing (Time, second, every)

type alias Model = { history : List (List Bool)

                  , cols : Int
                  , rows : Int
                  }

view : Model -> Html Msg view model =

 let 
   circleInBox (row,col) value = 
     if value 
     then [ Svg.circle [ r "0.3"
                       , fill ("purple")
                       , cx (toString (toFloat col + 0.5))
                       , cy (toString (toFloat row + 0.5))
                       ]            
                       []  
          ]
     else []
   showHistory model = 
     model.history 
       |> reverse
       |> fromList
       |> mapWithLocation circleInBox 
       |> flatten 
       |> concat 
 in
   div []
       [ h1 [] [text "One Dimensional Cellular Automata"]
       , svg [ version "1.1"
             , width "700"
             , height "700"
             , viewBox (join " "
                          [ 0 |> toString
                          , 0 |> toString
                          , model.cols |> toString
                          , model.rows |> toString
                          ]
                       )
             ] 
             (showHistory model)
       ]

update : Msg -> Model -> (Model, Cmd Msg) update msg model =

 if length model.history == model.rows
 then (model, Cmd.none)
 else
   let s1 = model.history |> head |> withDefault []
       s0 = False :: s1
       s2 = append (tail s1 |> withDefault []) [False]
   
       gen d0 d1 d2 = 
         case (d0,d1,d2) of
           (False,  True,  True) -> True
           ( True, False,  True) -> True
           ( True,  True, False) -> True
           _                     -> False
       updatedHistory = map3 gen s0 s1 s2 :: model.history
       updatedModel = {model | history = updatedHistory}
   in (updatedModel, Cmd.none)
   

init : Int -> (Model, Cmd Msg) init n =

 let gen1 = fst (step (list n bool) (initialSeed 34))
 in ({ history = [gen1], rows = n, cols= n }, Cmd.none)

type Msg = Tick Time

subscriptions model = every (0.2 * second) Tick

main = program

        {  init = init 40
        ,  view = view
        ,  update = update
        ,  subscriptions = subscriptions
        }</lang>

Link to live demo: https://dc25.github.io/oneDimensionalCellularAutomataElm/

Erlang

<lang erlang> -module(ca). -compile(export_all).

run(N,G) ->

   run(N,G,0).

run(GN,G,GN) ->

   io:fwrite("~B: ",[GN]),
   print(G);

run(N,G,GN) ->

   io:fwrite("~B: ",[GN]),
   print(G),
   run(N,next(G),GN+1).

print([]) ->

   io:fwrite("~n");

print([0|T]) ->

   io:fwrite("_"),
   print(T);

print([1|T]) ->

   io:fwrite("#"),
   print(T).

next([]) ->

   [];

next([_]) ->

   [0];

next([H,1|_]=G) ->

   next(G,[H]);

next([_|_]=G) ->

   next(G,[0]).

next([],Acc) ->

   lists:reverse(Acc);

next([0,_],Acc) ->

   next([],[0|Acc]);

next([1,X],Acc) ->

   next([],[X|Acc]);

next([0,X,0|T],Acc) ->

   next([X,0|T],[0|Acc]);

next([1,X,0|T],Acc) ->

   next([X,0|T],[X|Acc]);

next([0,X,1|T],Acc) ->

   next([X,1|T],[X|Acc]);

next([1,0,1|T],Acc) ->

   next([0,1|T],[1|Acc]);

next([1,1,1|T],Acc) ->

   next([1,1|T],[0|Acc]).

</lang> Example execution: <lang erlang> 44> ca:run(9,[0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0]). 0: __###_##_#_#_#_#__#___ 1: __#_#####_#_#_#_______ 2: ___##___##_#_#________ 3: ___##___###_#_________ 4: ___##___#_##__________ 5: ___##____###__________ 6: ___##____#_#__________ 7: ___##_____#___________ 8: ___##_________________ 9: ___##_________________ </lang>

ERRE

<lang ERRE> PROGRAM ONEDIM_AUTOMATA

! for rosettacode.org !

!VAR I,J,N,W,K

!$DYNAMIC DIM X[0],X2[0]

BEGIN

  DATA(20,0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0)
  PRINT(CHR$(12);)
  N=20      ! number of generation required
  READ(W)
  !$DIM X[W+1],X2[W+1]
  FOR I=1 TO W DO
     READ(X[I])
  END FOR
  FOR K=1 TO N DO
     PRINT("Generation";K;TAB(16);)
     FOR J=1 TO W DO
        IF X[J]=1 THEN PRINT("#";)  ELSE PRINT("_";) END IF
        IF X[J-1]+X[J]+X[J+1]=2 THEN X2[J]=1 ELSE X2[J]=0 END IF
     END FOR
     PRINT
     FOR J=1 TO W DO
        X[J]=X2[J]
     END FOR
  END FOR

END PROGRAM </lang>

Output:
Generation 1   _###_##_#_#_#_#__#__
Generation 2   _#_#####_#_#_#______
Generation 3   __##___##_#_#_______
Generation 4   __##___###_#________
Generation 5   __##___#_##_________
Generation 6   __##____###_________
Generation 7   __##____#_#_________
Generation 8   __##_____#__________
Generation 9   __##________________
Generation 10  __##________________
Generation 11  __##________________
Generation 12  __##________________
Generation 13  __##________________
Generation 14  __##________________
Generation 15  __##________________
Generation 16  __##________________
Generation 17  __##________________
Generation 18  __##________________
Generation 19  __##________________
Generation 20  __##________________

Euphoria

<lang euphoria>include machine.e

function rules(integer tri)

   return tri = 3 or tri = 5 or tri = 6

end function

function next_gen(atom gen)

   atom new, bit
   new = rules(and_bits(gen,3)*2) -- work with the first bit separately
   bit = 2
   while gen > 0 do
       new += bit*rules(and_bits(gen,7))
       gen = floor(gen/2) -- shift right
       bit *= 2 -- shift left
   end while
   return new

end function

constant char_clear = '_', char_filled = '#'

procedure print_gen(atom gen)

   puts(1, int_to_bits(gen,32) * (char_filled - char_clear) + char_clear)
   puts(1,'\n')

end procedure

function s_to_gen(sequence s)

   s -= char_clear
   return bits_to_int(s)

end function

atom gen, prev integer n

n = 0 prev = 0 gen = bits_to_int(rand(repeat(2,32))-1) while gen != prev do

   printf(1,"Generation %d: ",n)
   print_gen(gen)
   prev = gen
   gen = next_gen(gen)
   n += 1

end while

printf(1,"Generation %d: ",n) print_gen(gen)</lang>

Output:
Generation 0: ####__#_###_#_#_#_#_##___##_##__
Generation 1: ___#___##_##_#_#_#_###___#####__
Generation 2: _______######_#_#_##_#___#___#__
Generation 3: _______#____##_#_####___________
Generation 4: ____________###_##__#___________
Generation 5: ____________#_####______________
Generation 6: _____________##__#______________
Generation 7: _____________##_________________
Generation 8: _____________##_________________

Factor

<lang factor>USING: bit-arrays io kernel locals math sequences ; IN: cellular

bool-sum ( bool1 bool2 -- sum )
   [ [ 2 ] [ 1 ] if ]
   [ [ 1 ] [ 0 ] if ] if ;
neighbours ( index world -- # )
   index [ 1 - ] [ 1 + ] bi [ world ?nth ] bi@ bool-sum ;
count-neighbours ( world -- neighbours )
   [ length iota ] keep [ neighbours ] curry map ;
life-law ( alive? neighbours -- alive? )
   swap [ 1 = ] [ 2 = ] if ;
step ( world -- world' )
   dup count-neighbours [ life-law ] ?{ } 2map-as ;
print-cellular ( world -- )
   [ CHAR: # CHAR: _ ? ] "" map-as print ;
main-cellular ( -- )
   ?{ f t t t f t t f t f t f t f t f f t f f }
   10 [ dup print-cellular step ] times print-cellular ;

MAIN: main-cellular </lang>

( scratchpad ) "cellular" run
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________

Fantom

<lang fantom> class Automaton {

 static Int[] evolve (Int[] array)
 {
   return array.map |Int x, Int i -> Int|
   {
     if (i == 0) 
       return ( (x + array[1] == 2) ? 1 : 0)
     else if (i == array.size-1)
       return ( (x + array[-2] == 2) ? 1 : 0)
     else if (x + array[i-1] + array[i+1] == 2)
       return 1
     else
       return 0      
   }
 }
 public static Void main () 
 {
   Int[] array := [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]
   echo (array.join(""))
   Int[] newArray := evolve(array)
   while (newArray != array)
   {
     echo (newArray.join(""))
     array = newArray
     newArray = evolve(array)
   }
 }

} </lang>

FOCAL

<lang FOCAL>1.1 S OLD(2)=1; S OLD(3)=1; S OLD(4)=1; S OLD(6)=1; S OLD(7)=1 1.2 S OLD(9)=1; S OLD(11)=1; S OLD(13)=1; S OLD(15)=1; S OLD(18)=1 1.3 F N=1,10; D 2 1.4 Q

2.1 F X=1,20; D 3 2.2 F X=1,20; D 6 2.3 F X=1,20; S OLD(X)=NEW(X) 2.4 T !

3.1 I (OLD(X-1)+OLD(X)+OLD(X+1)-2)4.1,5.1,4.1

4.1 S NEW(X)=0

5.1 S NEW(X)=1

6.1 I (-OLD(X))7.1,8.1,8.1

7.1 T "#"

8.1 T "."</lang>

Output:
.###.##.#.#.#.#..#..
.#.#####.#.#.#......
..##...##.#.#.......
..##...###.#........
..##...#.##.........
..##....###.........
..##....#.#.........
..##.....#..........
..##................
..##................

Forth

<lang forth>: init ( bits count -- )

 0 do dup 1 and c, 2/ loop drop ;

20 constant size create state $2556e size init 0 c,

.state
 cr size 0 do
   state i + c@ if ." #" else space then
 loop ;
ctable create does> + c@ ;

ctable rules $68 8 init

gen
 state c@ ( window )
 size 0 do
   2*  state i + 1+ c@ or  7 and
   dup rules state i + c!
 loop drop ;
life1d ( n -- )
 .state 1 do gen .state loop ;

10 life1d</lang>

ouput <lang>

### ## # # # #  #  
# ##### # # #      
 ##   ## # #       
 ##   ### #        
 ##   # ##         
 ##    ###         
 ##    # #         
 ##     #          
 ##                
 ##                 ok

</lang>

Fortran

Works with: Fortran version 90 and later

<lang fortran>PROGRAM LIFE_1D

 IMPLICIT NONE
 LOGICAL :: cells(20) = (/ .FALSE., .TRUE., .TRUE., .TRUE., .FALSE., .TRUE., .TRUE., .FALSE., .TRUE., .FALSE., &
                           .TRUE., .FALSE., .TRUE., .FALSE., .TRUE., .FALSE., .FALSE., .TRUE., .FALSE., .FALSE. /)
 INTEGER :: i
 
 DO i = 0, 9
    WRITE(*, "(A,I0,A)", ADVANCE = "NO") "Generation ", i, ": "
    CALL Drawgen(cells)
    CALL Nextgen(cells)
 END DO

CONTAINS

 SUBROUTINE Nextgen(cells)
   LOGICAL, INTENT (IN OUT) :: cells(:)
   LOGICAL :: left, centre, right
   INTEGER :: i
  
   left = .FALSE.
   DO i = 1, SIZE(cells)-1
      centre = cells(i)
      right = cells(i+1)
      IF (left .AND. right) THEN
         cells(i) = .NOT. cells(i)
      ELSE IF (.NOT. left .AND. .NOT. right) THEN
         cells(i) = .FALSE.
      END IF
      left = centre
   END DO
   cells(SIZE(cells)) = left .AND. right
 END SUBROUTINE Nextgen
 SUBROUTINE Drawgen(cells)
   LOGICAL, INTENT (IN OUT) :: cells(:)
   INTEGER :: i
  
   DO i = 1, SIZE(cells)
      IF (cells(i)) THEN
         WRITE(*, "(A)", ADVANCE = "NO") "#"
      ELSE
         WRITE(*, "(A)", ADVANCE = "NO") "_"
      END IF
   END DO
   WRITE(*,*)
 END SUBROUTINE Drawgen
 

END PROGRAM LIFE_1D</lang>

Output:
 Generation 0: _###_##_#_#_#_#__#__ 
 Generation 1: _#_#####_#_#_#______ 
 Generation 2: __##___##_#_#_______ 
 Generation 3: __##___###_#________ 
 Generation 4: __##___#_##_________ 
 Generation 5: __##____###_________ 
 Generation 6: __##____#_#_________ 
 Generation 7: __##_____#__________ 
 Generation 8: __##________________ 
 Generation 9: __##________________

GFA Basic

<lang> ' ' One Dimensional Cellular Automaton ' start$="01110110101010100100" max_cycles%=20 ! give a maximum depth ' ' Global variables hold the world, with two rows ' world! is set up with 2 extra cells width, so there is a FALSE on either side ' cur% gives the row for current world, ' new% gives the row for the next world. ' size%=LEN(start$) DIM world!(size%+2,2) cur%=0 new%=1 clock%=0 ' @setup_world(start$) OPENW 1 CLEARW 1 DO

 @display_world
 @update_world
 EXIT IF @same_state
 clock%=clock%+1
 EXIT IF clock%>max_cycles% ! safety net

LOOP ~INP(2) CLOSEW 1 ' ' parse given string to set up initial states in world ' -- assumes world! is of correct size ' PROCEDURE setup_world(defn$)

 LOCAL i%
 ' clear out the array
 ARRAYFILL world!(),FALSE
 ' for each 1 in string, set cell to true
 FOR i%=1 TO LEN(defn$)
   IF MID$(defn$,i%,1)="1"
     world!(i%,0)=TRUE
   ENDIF
 NEXT i%
 ' set references to cur and new
 cur%=0
 new%=1

RETURN ' ' Display the world ' PROCEDURE display_world

 LOCAL i%
 FOR i%=1 TO size%
   IF world!(i%,cur%)
     PRINT "#";
   ELSE
     PRINT ".";
   ENDIF
 NEXT i%
 PRINT ""

RETURN ' ' Create new version of world ' PROCEDURE update_world

 LOCAL i%
 FOR i%=1 TO size%
   world!(i%,new%)=@new_state(@get_value(i%))
 NEXT i%
 ' reverse cur/new
 cur%=1-cur%
 new%=1-new%

RETURN ' ' Test if cur/new states are the same ' FUNCTION same_state

 LOCAL i%
 FOR i%=1 TO size%
   IF world!(i%,cur%)<>world!(i%,new%)
     RETURN FALSE
   ENDIF
 NEXT i%
 RETURN TRUE

ENDFUNC ' ' Return new state of cell given value ' FUNCTION new_state(value%)

 SELECT value%
 CASE 0,1,2,4,7
   RETURN FALSE
 CASE 3,5,6
   RETURN TRUE
 ENDSELECT

ENDFUNC ' ' Compute value for cell + neighbours ' FUNCTION get_value(cell%)

 LOCAL result%
 result%=0
 IF world!(cell%-1,cur%)
   result%=result%+4
 ENDIF
 IF world!(cell%,cur%)
   result%=result%+2
 ENDIF
 IF world!(cell%+1,cur%)
   result%=result%+1
 ENDIF
 RETURN result%

ENDFUNC </lang>

Go

Sequential

<lang go>package main

import "fmt"

const (

   start    = "_###_##_#_#_#_#__#__"
   offLeft  = '_'
   offRight = '_'
   dead     = '_'

)

func main() {

   fmt.Println(start)
   g := newGenerator(start, offLeft, offRight, dead)
   for i := 0; i < 10; i++ {
       fmt.Println(g())
   }

}

func newGenerator(start string, offLeft, offRight, dead byte) func() string {

   g0 := string(offLeft) + start + string(offRight)
   g1 := []byte(g0)
   last := len(g0) - 1
   return func() string {
       for i := 1; i < last; i++ {
           switch l := g0[i-1]; {
           case l != g0[i+1]:
               g1[i] = g0[i]
           case g0[i] == dead:
               g1[i] = l
           default:
               g1[i] = dead
           }
       }
       g0 = string(g1)
       return g0[1:last]
   }

}</lang>

Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________

Concurrent

Computations run on each cell concurrently. Separate read and write phases. Single array of cells. <lang go>package main

import (

   "fmt"
   "sync"

)

const (

   start    = "_###_##_#_#_#_#__#__"
   offLeft  = '_'
   offRight = '_'
   dead     = '_'

)

func main() {

   fmt.Println(start)
   a := make([]byte, len(start)+2)
   a[0] = offLeft
   copy(a[1:], start)
   a[len(a)-1] = offRight
   var read, write sync.WaitGroup
   read.Add(len(start) + 1)
   for i := 1; i <= len(start); i++ {
       go cell(a[i-1:i+2], &read, &write)
   }
   for i := 0; i < 10; i++ {
       write.Add(len(start) + 1)
       read.Done()
       read.Wait()
       read.Add(len(start) + 1)
       write.Done()
       write.Wait()
       fmt.Println(string(a[1 : len(a)-1]))
   }

}

func cell(kernel []byte, read, write *sync.WaitGroup) {

   var next byte
   for {
       l, v, r := kernel[0], kernel[1], kernel[2]
       read.Done()
       switch {
       case l != r:
           next = v
       case v == dead:
           next = l
       default:
           next = dead
       }
       read.Wait()
       kernel[1] = next
       write.Done()
       write.Wait()
   }

}</lang> Output is same as sequential version.

Groovy

Solution: <lang groovy>def life1D = { self ->

   def right = self[1..-1] + [false]
   def left = [false] + self[0..-2]
   [left, self, right].transpose().collect { hood -> hood.count { it } == 2 }

}</lang>

Test: <lang groovy>def cells = ('_###_##_#_#_#_#__#__' as List).collect { it == '#' } println "Generation 0: ${cells.collect { g -> g ? '#' : '_' }.join()}" (1..9).each {

   cells = life1D(cells)
   println "Generation ${it}: ${cells.collect { g -> g ? '#' : '_' }.join()}"

}</lang>

Output:
Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________

Haskell

<lang haskell>import Data.List (unfoldr) import System.Random (newStdGen, randomRs)

bnd :: String -> Char bnd "_##" = '#' bnd "#_#" = '#' bnd "##_" = '#' bnd _ = '_'

nxt :: String -> String nxt = unfoldr go . ('_' :) . (<> "_")

 where
   go [_, _] = Nothing
   go xs = Just (bnd $ take 3 xs, drop 1 xs)

lahmahgaan :: String -> [String] lahmahgaan xs =

 init
   . until
     ((==) . last <*> last . init)
     ((<>) <*> pure . nxt . last)
   $ [xs, nxt xs]

main :: IO () main =

 newStdGen
   >>= ( mapM_ putStrLn . lahmahgaan
           . map ("_#" !!)
           . take 36
           . randomRs (0, 1)
       )</lang>
Output:

For example:

_##_#_#__#_#_#_#_###_#######_#_#__##
_###_#____#_#_#_##_###_____##_#___##
_#_##______#_#_#####_#_____###____##
__###_______#_##___##______#_#____##
__#_#________###___##_______#_____##
___#_________#_#___##_____________##
______________#____##_____________##
___________________##_____________##

Icon and Unicon

<lang icon>

  1. One dimensional Cellular automaton

record Automaton(size, cells)

procedure make_automaton (size, items)

 automaton := Automaton (size, items)
 while (*items < size) do push (automaton.cells, 0)
 return automaton

end

procedure automaton_display (automaton)

 every (write ! automaton.cells)

end

procedure automaton_evolve (automaton)

 revised := make_automaton (automaton.size, [])
 # do the left-most cell
 if ((automaton.cells[1] + automaton.cells[2]) = 2) then
   revised.cells[1] := 1
 # do the right-most cell
 if ((automaton.cells[automaton.size] + automaton.cells[automaton.size-1]) = 2) then
   revised.cells[revised.size] := 1
 # do the intermediate cells
 every (i := 2 to (automaton.size-1)) do {
   if ((automaton.cells[i-1] + automaton.cells[i] + automaton.cells[i+1]) = 2) then
     revised.cells[i] := 1
 }
 return revised

end

procedure main ()

 automaton := make_automaton (20, [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0])
 every (1 to 10) do { # generations
   automaton_display (automaton)
   automaton := automaton_evolve (automaton)
 }

end </lang>

An alternative approach is to represent the automaton as a string. The following solution takes advantage of the implicit type coercions between string and numeric values in Icon and Unicon. It also surrounds the automaton with a border of 'dead' (always 0) cells to eliminate the need to special case the first and last cells in the automaton. Although the main procedure displays up to the first 10 generations, the evolve procedure fails if a new generation is unchanged from the previous, stopping the generation cycle early.

<lang unicon>procedure main(A)

 A := if *A = 0 then ["01110110101010100100"]
 CA := show("0"||A[1]||"0")        # add always dead border cells
 every CA := show(|evolve(CA)\10)  # limit to max of 10 generations

end

procedure show(ca)

 write(ca[2:-1])                   # omit border cells
 return ca

end

procedure evolve(CA)

 newCA := repl("0",*CA)
 every newCA[i := 2 to (*CA-1)] := (CA[i-1]+CA[i]+CA[i+1] = 2, "1")
 return CA ~== newCA               # fail if no change

end</lang>

A couple of sample runs:
->odca
01110110101010100100
01011111010101000000
00110001101010000000
00110001110100000000
00110001011000000000
00110000111000000000
00110000101000000000
00110000010000000000
00110000000000000000
->odca 01110110
01110110
01011110
00110010
00110000
->

J

<lang j>life1d=: '_#'{~ (2 = 3+/\ 0,],0:)^:a:</lang>

Example use:

<lang j> life1d ? 20 # 2 _###_##_#_#_#_#__#__ _#_#####_#_#_#______ __##___##_#_#_______ __##___###_#________ __##___#_##_________ __##____###_________ __##____#_#_________ __##_____#__________ __##________________</lang>

Alternative implementation:

<lang j>Rule=:2 :0 NB. , m: number of generations, n: rule number

 '_#'{~ (3 ((|.n#:~8#2) {~ #.)\ 0,],0:)^:(i.m)

)</lang>

Example use:

<lang j> 9 Rule 104 '#'='_###_##_#_#_#_#__#__' _###_##_#_#_#_#__#__ _#_#####_#_#_#______ __##___##_#_#_______ __##___###_#________ __##___#_##_________ __##____###_________ __##____#_#_________ __##_____#__________ __##________________</lang>

Java

This example requires a starting generation of at least length two (which is what you need for anything interesting anyway). <lang java>public class Life{ public static void main(String[] args) throws Exception{ String start= "_###_##_#_#_#_#__#__"; int numGens = 10; for(int i= 0; i < numGens; i++){ System.out.println("Generation " + i + ": " + start); start= life(start); } }

public static String life(String lastGen){ String newGen= ""; for(int i= 0; i < lastGen.length(); i++){ int neighbors= 0; if (i == 0){//left edge neighbors= lastGen.charAt(1) == '#' ? 1 : 0; } else if (i == lastGen.length() - 1){//right edge neighbors= lastGen.charAt(i - 1) == '#' ? 1 : 0; } else{//middle neighbors= getNeighbors(lastGen.substring(i - 1, i + 2)); }

if (neighbors == 0){//dies or stays dead with no neighbors newGen+= "_"; } if (neighbors == 1){//stays with one neighbor newGen+= lastGen.charAt(i); } if (neighbors == 2){//flips with two neighbors newGen+= lastGen.charAt(i) == '#' ? "_" : "#"; } } return newGen; }

public static int getNeighbors(String group){ int ans= 0; if (group.charAt(0) == '#') ans++; if (group.charAt(2) == '#') ans++; return ans; } }</lang>

Output:
Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______ 
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________
Translation of: C

In this version, b is replaced by a backup which is local to the evolve method, and the evolve method returns a boolean. <lang java>public class Life{ private static char[] trans = "___#_##_".toCharArray();

private static int v(StringBuilder cell, int i){ return (cell.charAt(i) != '_') ? 1 : 0; }

public static boolean evolve(StringBuilder cell){ boolean diff = false; StringBuilder backup = new StringBuilder(cell.toString());

for(int i = 1; i < cell.length() - 3; i++){ /* use left, self, right as binary number bits for table index */ backup.setCharAt(i, trans[v(cell, i - 1) * 4 + v(cell, i) * 2 + v(cell, i + 1)]); diff = diff || (backup.charAt(i) != cell.charAt(i)); }

cell.delete(0, cell.length());//clear the buffer cell.append(backup);//replace it with the new generation return diff; }

public static void main(String[] args){ StringBuilder c = new StringBuilder("_###_##_#_#_#_#__#__\n");

do{ System.out.printf(c.substring(1)); }while(evolve(c)); } }</lang>

Output:
###_##_#_#_#_#__#__
#_#####_#_#_#______
_##___##_#_#_______
_##___###_#________
_##___#_##_________
_##____###_________
_##____#_#_________
_##_____#__________
_##________________

JavaScript

The example below expects an array of 1s or 0s, as in the example. It also adds dead cells to both ends, which aren't included in the returned next generation.

state[i-1] refers to the new cell in question, (old[i] == 1) checks if the old cell was alive. <lang javascript>function caStep(old) {

 var old = [0].concat(old, [0]); // Surround with dead cells.
 var state = []; // The new state.
 
 for (var i=1; i<old.length-1; i++) {
   switch (old[i-1] + old[i+1]) {
     case 0: state[i-1] = 0; break;
     case 1: state[i-1] = (old[i] == 1) ? 1 : 0; break;
     case 2: state[i-1] = (old[i] == 1) ? 0 : 1; break;
   }
 }
 return state;

}</lang>

Example usage:

<lang javascript>alert(caStep([0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]));</lang> shows an alert with "0,1,0,1,1,1,1,1,0,1,0,1,0,1,0,0,0,0,0,0".

jq

The main point of interest in the following is perhaps the way the built-in function "recurse" is used to continue the simulation until quiescence. <lang jq># The 1-d cellular automaton: def next:

  # Conveniently, jq treats null as 0 when it comes to addition
  # so there is no need to fiddle with the boundaries
 . as $old
 | reduce range(0; length) as $i
   ([];
    ($old[$i-1] + $old[$i+1]) as $s
    | if   $s == 0 then .[$i] = 0
      elif $s == 1 then .[$i] = (if $old[$i] == 1 then 1 else 0 end)
      else              .[$i] = (if $old[$i] == 1 then 0 else 1 end)
      end);


  1. pretty-print an array:

def pp: reduce .[] as $i (""; . + (if $i == 0 then " " else "*" end));

  1. continue until quiescence:

def go: recurse(. as $prev | next | if . == $prev then empty else . end) | pp;

  1. Example:

[0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0] | go</lang>

Output:

<lang sh>$ jq -c -r -n -f One-dimensional_cellular_automata.jq

*** ** * * * *  *  
* ***** * * *      
 **   ** * *       
 **   *** *        
 **   * **         
 **    ***         
 **    * *         
 **     *          
 **</lang>

Julia

This solution creates an automaton with with either empty or periodic bounds. The empty bounds case, is typical of many of the solutions here. The periodic bounds case is a typical physics approach where, in effect, the beginning and end of the list touch each other to form a circular rather than linear array. In practice, the effects of boundary conditions are subtle for long arrays. <lang Julia> function next_gen(a::BitArray{1}, isperiodic=false)

   b = copy(a)
   if isperiodic
       ncnt = prepend!(a[1:end-1], [a[end]]) + append!(a[2:end], [a[1]])
   else
       ncnt = prepend!(a[1:end-1], [false]) + append!(a[2:end], [false])
   end
   b[ncnt .== 0] = false
   b[ncnt .== 2] = ~b[ncnt .== 2]
   return b

end

function show_gen(a::BitArray{1})

   s = join([i ? "\u2588" : " " for i in a], "")
   s = "\u25ba"*s*"\u25c4"

end

hi = 70 a = bitrand(hi) b = falses(hi) println("A 1D Cellular Atomaton with ", hi, " cells and empty bounds.") while any(a) && any(a .!= b)

   println("    ", show_gen(a))
   b = copy(a)
   a = next_gen(a)

end a = bitrand(hi) b = falses(hi) println() println("A 1D Cellular Atomaton with ", hi, " cells and periodic bounds.") while any(a) && any(a .!= b)

   println("    ", show_gen(a))
   b = copy(a)
   a = next_gen(a, true)

end </lang>

Output:
A 1D Cellular Atomaton with 70 cells and empty bounds.
    ► ███  ██  █ ██   ███ █  ███  ██  █ █   ██████ █   ██ █ █ █  █ ██  ███ ◄
    ► █ █  ██   ███   █ ██   █ █  ██   █    █    ██    ███ █ █    ███  █ █ ◄
    ►  █   ██   █ █    ███    █   ██             ██    █ ██ █     █ █   █  ◄
    ►      ██    █     █ █        ██             ██     ████       █       ◄
    ►      ██           █         ██             ██     █  █               ◄
    ►      ██                     ██             ██                        ◄

A 1D Cellular Atomaton with 70 cells and periodic bounds.
    ►████   ██ █    █ █  ██  ██ █ █      ████   █    ███  ███ ██     ██ ██ ◄
    ►█  █   ███      █   ██  ███ █       █  █        █ █  █ ████     ██████◄
    ►█      █ █          ██  █ ██                     █    ██  █     █     ◄
    ►        █           ██   ███                          ██              ◄
    ►                    ██   █ █                          ██              ◄
    ►                    ██    █                           ██              ◄
    ►                    ██                                ██              ◄

K

<lang K>f:{2=+/(0,x,0)@(!#x)+/:!3}</lang>

Example usage:

<lang K> `0:"_X"@f\0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0 _XXX_XX_X_X_X_X__X__ _X_XXXXX_X_X_X______ __XX___XX_X_X_______ __XX___XXX_X________ __XX___X_XX_________ __XX____XXX_________ __XX____X_X_________ __XX_____X__________ __XX________________ </lang>

Kotlin

Translation of: C

<lang scala>// version 1.1.4-3

val trans = "___#_##_"

fun v(cell: StringBuilder, i: Int) = if (cell[i] != '_') 1 else 0

fun evolve(cell: StringBuilder, backup: StringBuilder): Boolean {

   val len = cell.length - 2
   var diff = 0
   for (i in 1 until len) {
       /* use left, self, right as binary number bits for table index */
       backup[i] = trans[v(cell, i - 1) * 4 + v(cell, i) * 2 + v(cell, i + 1)]
       diff += if (backup[i] != cell[i]) 1 else 0
   }
   cell.setLength(0)
   cell.append(backup)
   return diff != 0

}

fun main(args: Array<String>) {

   val c = StringBuilder("_###_##_#_#_#_#__#__")
   val b = StringBuilder("____________________")
   do {
      println(c.substring(1))
   }
   while (evolve(c,b))

}</lang>

Output:
###_##_#_#_#_#__#__
#_#####_#_#_#______
_##___##_#_#_______
_##___###_#________
_##___#_##_________
_##____###_________
_##____#_#_________
_##_____#__________
_##________________

Liberty BASIC

Works with: Just BASIC
Works with: Run BASIC

<lang lb>' [RC] 'One-dimensional cellular automata'

' does not wrap so fails for some rules rule$ ="00010110" ' Rule 22 decimal

state$ ="0011101101010101001000"

for j =1 to 20

   print state$
   oldState$ =state$
   state$ ="0"
   for k =2 to len( oldState$) -1
       NHood$ =mid$( oldState$, k -1, 3)  '   pick 3 char neighbourhood and turn binary string to decimal
       vNHood =0
       for kk =3 to 1 step -1
           vNHood =vNHood +val( mid$( NHood$, kk, 1)) *2^( 3 -kk)
       next kk
                                       '  .... & use it to index into rule$ to find appropriate new value
       state$ =state$ +mid$( rule$, vNHood +1, 1)
   next k
   state$ =state$ +"0" 

next j

end</lang>

Locomotive Basic

<lang locobasic>10 MODE 1:n=10:READ w:DIM x(w+1),x2(w+1):FOR i=1 to w:READ x(i):NEXT 20 FOR k=1 TO n 30 FOR j=1 TO w 40 IF x(j) THEN PRINT "#"; ELSE PRINT "_"; 50 IF x(j-1)+x(j)+x(j+1)=2 THEN x2(j)=1 ELSE x2(j)=0 60 NEXT:PRINT 70 FOR j=1 TO w:x(j)=x2(j):NEXT 80 NEXT 90 DATA 20,0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0</lang>

Output:

Works with: UCB Logo

<lang logo>make "cell_list [0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0] make "generations 9

to evolve :n ifelse :n=1 [make "nminus1 item :cell_count :cell_list][make "nminus1 item :n-1 :cell_list] ifelse :n=:cell_count[make "nplus1 item 1 :cell_list][make "nplus1 item :n+1 :cell_list] ifelse ((item :n :cell_list)=0) [ ifelse (and (:nminus1=1) (:nplus1=1)) [output 1][output (item :n :cell_list)] ][ ifelse (and (:nminus1=1) (:nplus1=1)) [output 0][ ifelse and (:nminus1=0) (:nplus1=0) [output 0][output (item :n :cell_list)]] ] end

to CA_1D :cell_list :generations make "cell_count count :cell_list (print ") make "printout " repeat :cell_count [ make "printout word :printout ifelse (item repcount :cell_list)=1 ["#]["_] ] (print "Generation "0: :printout)

repeat :generations [

      (make "cell_list_temp [])
      repeat :cell_count[
            (make "cell_list_temp (lput (evolve repcount) :cell_list_temp))
      ]
      make "cell_list :cell_list_temp
      make "printout "
      repeat :cell_count [
      	      make "printout word :printout ifelse (item repcount :cell_list)=1 ["#]["_]
      ]
      (print "Generation  word repcount ": :printout)

] end

CA_1D :cell_list :generations</lang>

Output:
Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________

Lua

<lang lua>num_iterations = 9 f = { 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0 }

function Output( f, l )

   io.write( l, ":  " )
   for i = 1, #f do
       local c
       if f[i] == 1 then c = '#' else c = '_' end
       io.write( c )
   end
   print ""

end

Output( f, 0 )

for l = 1, num_iterations do

   local g = {}
   for i = 2, #f-1 do
       if f[i-1] + f[i+1] == 1 then 
           g[i] = f[i]
       elseif f[i] == 0 and f[i-1] + f[i+1] == 2 then
           g[i] = 1
       else
           g[i] = 0 
       end
   end
   if f[1]  == 1 and f[2]    == 1 then g[1]  = 1 else g[1]  = 0 end
   if f[#f] == 1 and f[#f-1] == 1 then g[#f] = 1 else g[#f] = 0 end        
   f, g = g, f
   Output( f, l )

end </lang>

Output:
0:  _###_##_#_#_#_#__#__
1:  _#_#####_#_#_#______
2:  __##___##_#_#_______
3:  __##___###_#________
4:  __##___#_##_________
5:  __##____###_________
6:  __##____#_#_________
7:  __##_____#__________
8:  __##________________
9:  __##________________

M4

<lang M4>divert(-1) define(`set',`define(`$1[$2]',`$3')') define(`get',`defn(`$1[$2]')') define(`setrange',`ifelse(`$3',`',$2,`define($1[$2],$3)`'setrange($1,

  incr($2),shift(shift(shift($@))))')')

dnl throw in sentinels at each end (0 and size+1) to make counting easy define(`new',`set($1,size,eval($#-1))`'setrange($1,1,

  shift($@))`'set($1,0,0)`'set($1,$#,0)')

define(`for',

  `ifelse($#,0,``$0,
  `ifelse(eval($2<=$3),1,
  `pushdef(`$1',$2)$4`'popdef(`$1')$0(`$1',incr($2),$3,`$4')')')')

define(`show',

  `for(`k',1,get($1,size),`get($1,k) ')')

dnl swap(`a',a,`b') using arg stack for temp define(`swap',`define(`$1',$3)`'define(`$3',$2)') define(`nalive',

  `eval(get($1,decr($2))+get($1,incr($2)))')

setrange(`live',0,0,1,0) setrange(`dead',0,0,0,1) define(`nv',

  `ifelse(get($1,z),0,`get(dead,$3)',`get(live,$3)')')

define(`evolve',

  `for(`z',1,get($1,size),
     `set($2,z,nv($1,z,nalive($1,z)))')')

new(`a',0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0) set(`b',size,get(`a',size))`'set(`b',0,0)`'set(`b',incr(get(`a',size)),0) define(`x',`a') define(`y',`b') divert for(`j',1,10,

  `show(x)`'evolve(`x',`y')`'swap(`x',x,`y')

')`'show(x)</lang>

Output:
0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0
0 1 0 1 1 1 1 1 0 1 0 1 0 1 0 0 0 0 0 0
0 0 1 1 0 0 0 1 1 0 1 0 1 0 0 0 0 0 0 0
0 0 1 1 0 0 0 1 1 1 0 1 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 1 0 1 1 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Mathematica / Wolfram Language

Built-in function: <lang Mathematica>CellularAutomaton[{{0,0,_}->0,{0,1,0}->0,{0,1,1}->1,{1,0,0}->0,{1,0,1}->1,{1,1,0}->1,{1,1,1}->0},{{1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1},0},12] Print @@@ (% /. {1 -> "#", 0 -> "."});</lang> For succinctness, an integral rule can be used: <lang Mathematica>CellularAutomaton[2^^01101000 (* == 104 *), {{1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1}, 0}, 12];</lang>

Output:

<lang Mathematica>###.##.#.#.#.#..#

  1. .#####.#.#.#....

.##...##.#.#..... .##...###.#...... .##...#.##....... .##....###....... .##....#.#....... .##.....#........ .##.............. .##.............. .##.............. .##.............. .##..............</lang>

MATLAB / Octave

<lang MATLAB>function one_dim_cell_automata(v,n)

  V='_#';
  while n>=0;

disp(V(v+1)); n = n-1; v = filter([1,1,1],1,[0,v,0]); v = v(3:end)==2;

  end; 

end</lang>

Output:
octave:27> one_dim_cell_automata('01110110101010100100'=='1',20);
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________
...

Modula-3

Translation of: Ada

Modula-3 provides a module Word for doing bitwise operations, but it segfaults when trying to use BOOLEAN types, so we use INTEGER instead. <lang modula3>MODULE Cell EXPORTS Main;

IMPORT IO, Fmt, Word;

VAR culture := ARRAY [0..19] OF INTEGER {0, 1, 1, 1,

                                        0, 1, 1, 0, 
                                        1, 0, 1, 0, 
                                        1, 0, 1, 0, 
                                        0, 1, 0, 0};

PROCEDURE Step(VAR culture: ARRAY OF INTEGER) =

 VAR left: INTEGER := 0;
     this, right: INTEGER;
 BEGIN
   FOR i := FIRST(culture) TO LAST(culture) - 1 DO
     right := culture[i + 1];
     this := culture[i];
     culture[i] := 
         Word.Or(Word.And(this, Word.Xor(left, right)), Word.And(Word.Not(this), Word.And(left, right)));
     left := this;
   END;
   culture[LAST(culture)] := Word.And(culture[LAST(culture)], Word.Not(left));
 END Step;

PROCEDURE Put(VAR culture: ARRAY OF INTEGER) =

 BEGIN
   FOR i := FIRST(culture) TO LAST(culture) DO
     IF culture[i] = 1 THEN
       IO.PutChar('#');
     ELSE
       IO.PutChar('_');
     END;
   END;
 END Put;

BEGIN

 FOR i := 0 TO 9 DO
   IO.Put("Generation " & Fmt.Int(i) & " ");
   Put(culture);
   IO.Put("\n");
   Step(culture);
 END;

END Cell.</lang>

Output:
Generation 0 _###_##_#_#_#_#__#__
Generation 1 _#_#####_#_#_#______
Generation 2 __##___##_#_#_______
Generation 3 __##___###_#________
Generation 4 __##___#_##_________
Generation 5 __##____###_________
Generation 6 __##____#_#_________
Generation 7 __##_____#__________
Generation 8 __##________________
Generation 9 __##________________

MontiLang

<lang MontiLang>30 VAR length . 35 VAR height . FOR length 0 ENDFOR 1 0 ARR VAR list . length 1 - VAR topLen . FOR topLen 0 ENDFOR 1 ARR VAR topLst .

DEF getNeighbors

   1 - VAR tempIndex . 
   GET tempIndex SWAP 
   tempIndex 1 + VAR tempIndex .
   GET tempIndex SWAP 
   tempIndex 1 + VAR tempIndex .
   GET tempIndex SWAP .
   FOR 3 TOSTR ROT ENDFOR
   FOR 2 SWAP + ENDFOR  

ENDDEF

DEF printArr

   LEN 1 - VAR stLen .
   0 VAR j .
   FOR stLen
       GET j 
       TOSTR OUT .
       j 1 + VAR j .
   ENDFOR
   || PRINT .

ENDDEF

FOR height

   FOR length 0 ENDFOR ARR VAR next .
   1 VAR i .
   FOR length
       list i getNeighbors VAR last . 
       i 1 - VAR ind .
       last |111| == 
       IF : .
           next 0 INSERT ind
       ENDIF
       last |110| ==
       IF : .
           next 1 INSERT ind
       ENDIF
       last |101| ==
       IF : .
           next 1 INSERT ind
       ENDIF
       last |100| ==
       IF : .
           next 0 INSERT ind
       ENDIF
       last |011| ==
       IF : .
           next 1 INSERT ind
       ENDIF
       last |010| ==
       IF : .
           next 1 INSERT ind
       ENDIF
       last |001| ==
       IF : .
           next 1 INSERT ind
       ENDIF
       last |000| ==
       IF : .
           next 0 INSERT ind
       ENDIF
       clear
       i 1 + VAR i .
   ENDFOR 
   next printArr .
   next 0 ADD APPEND . VAR list .

ENDFOR</lang>

Nial

(life.nial) <lang nial>% we need a way to write a values and pass the same back wi is rest link [write, pass] % calculate the neighbors by rotating the array left and right and joining them neighbors is pack [pass, sum [-1 rotate, 1 rotate]] % calculate the individual birth and death of a single array element igen is fork [ = [ + [first, second], 3 first], 0 first, = [ + [first, second], 2 first], 1 first, 0 first ] % apply that to the array nextgen is each igen neighbors % 42 life is fork [ > [sum pass, 0 first], life nextgen wi, pass ]</lang>

Using it:

<lang nial>|loaddefs 'life.nial' |I := [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0] |life I</lang>

Nim

<lang Nim>import random


type

 BoolArray  = array[30, bool]
 Symbols    = array[bool, char]


proc neighbours(map: BoolArray, i: int): int =

 if i > 0:             inc(result, int(map[i - 1]))
 if i + 1 < len(map):  inc(result, int(map[i + 1]))

proc print(map: BoolArray, symbols: Symbols) =

 for i in map: write(stdout, symbols[i])
 write(stdout, "\l")

proc randomMap: BoolArray =

 randomize()
 for i in mitems(result): i = sample([true, false])


const

 num_turns = 20
 symbols   = ['_', '#']
 T = true
 F = false

var map =

 [F, T, T, T, F, T, T, F, T, F, T, F, T, F, T,
   F, F, T, F, F, F, F, F, F, F, F, F, F, F, F]
  1. map = randomMap() # uncomment for random start

print(map, symbols)

for _ in 0 ..< num_turns:

 var map2 = map
 for i, v in pairs(map):
   map2[i] =
     if v: neighbours(map, i) == 1
     else: neighbours(map, i) == 2
 print(map2, symbols)
 if map2 == map: break
 map = map2</lang>
Output:
_###_##_#_#_#_#__#____________
_#_#####_#_#_#________________
__##___##_#_#_________________
__##___###_#__________________
__##___#_##___________________
__##____###___________________
__##____#_#___________________
__##_____#____________________
__##__________________________
__##__________________________

Using a string character counting method: <lang nim>import strutils

const

 s_init: string = "_###_##_#_#_#_#__#__"
 arrLen: int = 20
 

var q0: string = s_init & repeat('_',arrLen-20) var q1: string = q0

proc life(s:string): char =

  var str: string = s
  if len(normalize(str)) == 2:      # normalize eliminates underscores
     return '#'
  return '_'
  

proc evolve(q: string): string =

  result = repeat('_',arrLen)
  #result[0] = '_'
  for i in 1 .. q.len-1:
     result[i] = life(substr(q & '_',i-1,i+1))

echo(q1) q1 = evolve(q0) echo(q1) while q1 != q0:

  q0 = q1
  q1 = evolve(q0)
  echo(q1)</lang>
Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________

Using nested functions and method calling style: <lang Nim>proc cellAutomata =

 proc evolveInto(x, t : var string) =
   for i in x.low..x.high:
     let
       alive = x[i] == 'o'
       left  = if i == x.low:  false else: x[i - 1] == 'o'
       right = if i == x.high: false else: x[i + 1] == 'o'
     t[i] =
       if alive: (if left xor right: 'o' else: '.')
       else:     (if left and right: 'o' else: '.')
 var
   x = ".ooo.oo.o.o.o.o..o.."
   t = x
 for i in 1..10:
   x.echo
   x.evolveInto t
   swap t, x

cellAutomata()</lang>

Output:
.ooo.oo.o.o.o.o..o..
.o.ooooo.o.o.o......
..oo...oo.o.o.......
..oo...ooo.o........
..oo...o.oo.........
..oo....ooo.........
..oo....o.o.........
..oo.....o..........
..oo................
..oo................

OCaml

<lang ocaml>let get g i =

 try g.(i)
 with _ -> 0

let next_cell g i =

 match get g (i-1), get g (i), get g (i+1) with
 | 0, 0, 0 -> 0
 | 0, 0, 1 -> 0
 | 0, 1, 0 -> 0
 | 0, 1, 1 -> 1
 | 1, 0, 0 -> 0
 | 1, 0, 1 -> 1
 | 1, 1, 0 -> 1
 | 1, 1, 1 -> 0
 | _ -> assert(false)

let next g =

 let old_g = Array.copy g in
 for i = 0 to pred(Array.length g) do
   g.(i) <- (next_cell old_g i)
 done

let print_g g =

 for i = 0 to pred(Array.length g) do
   if g.(i) = 0
   then print_char '_'
   else print_char '#'
 done;
 print_newline()</lang>

put the code above in a file named "life.ml", and then use it in the ocaml toplevel like this:

#use "life.ml" ;;

let iter n g =
  for i = 0 to n do
    Printf.printf "Generation %d: " i; print_g g;
    next g;
  done
;;

let g_of_string str =
  let f = (function '_' -> 0 | '#' -> 1 | _ -> assert false) in
  Array.init (String.length str) (fun i -> f str.[i])
;;

# iter 9 (g_of_string "_###_##_#_#_#_#__#__") ;;
Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________
- : unit = ()

Oforth

<lang Oforth>: nextGen( l ) | i s |

  l byteSize dup ->s String newSize
  s loop: i [ 
     i 1 if=: [ 0 ] else: [ i 1- l byteAt '#' = ]
     i l byteAt '#' = + 
     i s if=: [ 0 ] else: [ i 1+ l byteAt '#' = ] + 
     2 if=: [ '#' ] else: [ '_' ] over add
     ]
gen( l n -- )
   l dup .cr #[ nextGen dup .cr ] times( n ) drop ;</lang>
Output:
"_###_##_#_#_#_#__#__" 10 gen
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________
ok

Oz

<lang oz>declare

 A0 = {List.toTuple unit "_###_##_#_#_#_#__#__"}
 MaxGenerations = 9
 Rules = unit('___':&_
              '__#':&_
              '_#_':&_
              '_##':&#
              '#__':&_
              '#_#':&#
              '##_':&#
              '###':&_)
 fun {Evolve A}
    {Record.mapInd A
     fun {$ I V}
        Left = {CondSelect A I-1 &_}
        Right = {CondSelect A I+1 &_}
        Env = {String.toAtom [Left V Right]}
     in
        Rules.Env
     end
    }
 end
 fun lazy {Iterate X F}
    X|{Iterate {F X} F}
 end

in

 for
    I in 0..MaxGenerations
    A in {Iterate A0 Evolve}
 do
    {System.showInfo "Gen. "#I#": "#{Record.toList A}}
 end</lang>
Output:
Gen. 0: _###_##_#_#_#_#__#__
Gen. 1: _#_#####_#_#_#______
Gen. 2: __##___##_#_#_______
Gen. 3: __##___###_#________
Gen. 4: __##___#_##_________
Gen. 5: __##____###_________
Gen. 6: __##____#_#_________
Gen. 7: __##_____#__________
Gen. 8: __##________________
Gen. 9: __##________________

PARI/GP

This version defines the fixed cells to the left and right as dead; of course other versions are possible. This function generates one generation from a previous one, passed as a 0-1 vector. <lang parigp>step(v)=my(u=vector(#v),k);u[1]=v[1]&v[2];u[#u]=v[#v]&v[#v-1];for(i=2,#v-1,k=v[i-1]+v[i+1];u[i]=if(v[i],k==1,k==2));u;</lang>

To simulate a run of 10 generations of the automaton, the function above can be put in a loop that spawns a new generation as a function of nth generations passed (n=0 is the initial state):

<lang parigp>cur = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]; for(n=0, 9, print(cur); cur = step(cur));</lang>

Output

<lang> [0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0] [0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0] [0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0] [0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0] [0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0] [0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0] [0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0] [0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0] [0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0] [0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0] </lang>

Pascal

<lang pascal>program Test; {$IFDEF FPC}{$MODE DELPHI}{$ELSE}{$APPTYPE}{$ENDIF} uses

 sysutils;

const

 cCHAR: array[0..1] of char = ('_','#');

type

 TRow =  array of byte;

function ConvertToRow(const s:string):tRow; var

 i : NativeInt;

Begin

 i := length(s);
 setlength(Result,length(s));
 For i := i downto 0 do
   result[i-1]:= ORD(s[i]=cChar[1]);

end;

function OutRow(const row:tRow):string; //create output string var

 i: NativeInt;

Begin

 i := length(row);
 setlength(result,i);
 For i := i downto 1 do
   result[i]:= cChar[row[i-1]];

end;

procedure NextRow(row:pByteArray;MaxIdx:NativeInt); //compute next row in place by the using a small storage for the //2 values, that would otherwise be overridden var

 leftValue,Value: NativeInt;
 i,trpCnt: NativeInt;

Begin

 leftValue := 0;
 trpCnt := row[0]+row[1];
 i := 0;
 while i < MaxIdx do
 Begin
   Value := row[i];
   //the rule for survive : PopCnt == 2
   row[i] := ORD(trpCnt= 2);
   //reduce popcnt of element before
   dec(trpCnt,leftValue);
   //goto next element
   inc(i);
   leftValue := Value;
   //increment popcnt by right element
   inc(trpCnt,row[i+1]);
   //move to next position in ring buffer
 end;
 row[MaxIdx] := ORD(trpCnt= 2);

end;

const

 TestString: string='  ### ## # # # #  #  ';

var

 s: string;
 row:tRow;
 i: NativeInt;

begin

 s := Teststring;
 row:= ConvertToRow(s);
 For i := 0 to 9 do
 Begin
   writeln(OutRow(row));
   NextRow(@row[0],High(row));
 end;

end.</lang>

Output:

__###_##_#_#_#_#__#__ __#_#####_#_#_#______ ___##___##_#_#_______ ___##___###_#________ ___##___#_##_________ ___##____###_________ ___##____#_#_________ ___##_____#__________ ___##________________

___##________________

Perl

Use regexp to extract and substitute cells while the string changes

Convert cells to zeros and ones to set complement state <lang perl> $_="_###_##_#_#_#_#__#__\n"; do {

 y/01/_#/;
 print;
 y/_#/01/;
 s/(?<=(.))(.)(?=(.))/$1 == $3 ? $1 ? 1-$2 : 0 : $2/eg;

} while ($x ne $_ and $x=$_); </lang>

Use hash for complement state <lang perl> $_="_###_##_#_#_#_#__#__\n"; %h=qw(# _ _ #); do {

 print;
 s/(?<=(.))(.)(?=(.))/$1 eq $3 ? $1 eq "_" ? "_" : $h{$2} : $2/eg;

} while ($x ne $_ and $x=$_); </lang>

Output:

for both versions

_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________

Phix

Ludicrously optimised:

string s = "_###_##_#_#_#_#__#__"
integer prev='_', curr, toggled = 1

while 1 do
    ?s
    for i=2 to length(s)-1 do
        curr = s[i]
        if prev=s[i+1] 
        and (curr='#' or prev='#') then
            s[i] = 130-curr
            toggled = 1
        end if
        prev = curr
    end for
    if not toggled then ?s exit end if
    toggled = 0
end while
Output:
"_###_##_#_#_#_#__#__"
"_#_#####_#_#_#______"
"__##___##_#_#_______"
"__##___###_#________"
"__##___#_##_________"
"__##____###_________"
"__##____#_#_________"
"__##_____#__________"
"__##________________"
"__##________________"

And of course I had to have a crack at that Sierpinski_Triangle:

string s = "________________________#________________________"
integer prev='_', curr, toggled = 1
 
for limit=1 to 24 do
    ?s
    for i=2 to length(s)-1 do
        curr = s[i]
        if (prev=s[i+1]) = (curr='#') then
            s[i] = 130-curr
        end if
        prev = curr
    end for
end for
Output:
"________________________#________________________"
"_______________________#_#_______________________"
"______________________#___#______________________"
"_____________________#_#_#_#_____________________"
"____________________#_______#____________________"
"___________________#_#_____#_#___________________"
"__________________#___#___#___#__________________"
"_________________#_#_#_#_#_#_#_#_________________"
"________________#_______________#________________"
"_______________#_#_____________#_#_______________"
"______________#___#___________#___#______________"
"_____________#_#_#_#_________#_#_#_#_____________"
"____________#_______#_______#_______#____________"
"___________#_#_____#_#_____#_#_____#_#___________"
"__________#___#___#___#___#___#___#___#__________"
"_________#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_________"
"________#_______________________________#________"
"_______#_#_____________________________#_#_______"
"______#___#___________________________#___#______"
"_____#_#_#_#_________________________#_#_#_#_____"
"____#_______#_______________________#_______#____"
"___#_#_____#_#_____________________#_#_____#_#___"
"__#___#___#___#___________________#___#___#___#__"
"_#_#_#_#_#_#_#_#_________________#_#_#_#_#_#_#_#_"

Phixmonti

<lang Phixmonti>0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0 stklen var w w tolist 0 0 put 0 w 1 + repeat var x2

10 for drop w for var j j get 1 == if "#" else "_" endif print j 1 - get var p1 j get swap j 1 + get rot p1 + + 2 == x2 swap j set var x2 endfor nl drop x2 endfor</lang>

Picat

<lang Picat>go =>

  %    _ # # # _ # # _ # _ # _ # _ # _ _ # _ _
  S = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0],
  println(init=S),
  run_ca(S),
  nl,
  println("Some random inits:"),
  _ = random2(),
  foreach(N in [5,10,20,50])
    S2 = [random() mod 2 : _I in 1..N],
    run_ca(S2),
    nl
   end.

% % Run a CA and show the result. %

% rule/1 is the default run_ca(S) =>

 run_ca(S,rule).

run_ca(S,Rules) =>

 Len = S.length,
 All := [S],
 Seen = new_map(), % detect fixpoint and cycle
 while (not Seen.has_key(S))
   Seen.put(S,1),
   T = [S[1]] ++ [apply(Rules, slice(S,I-1,I+1)) : I in 2..Len-1] ++ [S[Len]],
   All := All ++ [T],
   S := T
 end,
 foreach(A in All) println(A.convert()) end,
 writeln(len=All.length).

% Convert: % 0->"_" % 1->"#" convert(L) = Res =>

   B = "_#",
   Res = [B[L[I]+1] : I in 1..L.length].

% the rules rule([0,0,0]) = 0. % rule([0,0,1]) = 0. % rule([0,1,0]) = 0. % Dies without enough neighbours rule([0,1,1]) = 1. % Needs one neighbour to survive rule([1,0,0]) = 0. % rule([1,0,1]) = 1. % Two neighbours giving birth rule([1,1,0]) = 1. % Needs one neighbour to survive rule([1,1,1]) = 0. % Starved to death.</lang>

Output:
init = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
len = 10

Some random inits:
_###_
_#_#_
__#__
_____
_____
len = 5

_#___##_#_
_____###__
_____#_#__
______#___
__________
__________
len = 6

###__####_#___#___##
#_#__#__##________##
##______##________##
##______##________##
len = 4

______###_#_#___####__#_______#__#___#_####__#_###
______#_##_#____#__#__________________##__#___##_#
_______####___________________________##______####
_______#__#___________________________##______#__#
______________________________________##_________#
______________________________________##_________#
len = 6


The program is fairly general. Here's the additional code for the rule 30 CA. <lang Picat>go2 =>

  N = 4,
  Ns = [0 : _ in 1..N],
  S = Ns ++ [1] ++ Ns,
  run_ca(S, rule30).

% The rules for rule 30 rule30([0,0,0]) = 0. rule30([0,0,1]) = 1. rule30([0,1,0]) = 1. rule30([0,1,1]) = 1. rule30([1,0,0]) = 1. rule30([1,0,1]) = 0. rule30([1,1,0]) = 0. rule30([1,1,1]) = 0.</lang>

PicoLisp

<lang PicoLisp>(let Cells (chop "_###_##_#_#_#_#__#__")

  (do 10
     (prinl Cells)
     (setq Cells
        (make
           (link "_")
           (map
              '((L)
                 (case (head 3 L)
                    (`(mapcar chop '("___" "__#" "_#_" "#__" "###"))
                        (link "_") )
                    (`(mapcar chop '("_##" "#_#" "##_"))
                       (link "#") ) ) )
              Cells )
           (link "_") ) ) ) )</lang>
Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________

Prolog

Works ith SWI-Prolog. <lang Prolog>one_dimensional_cellular_automata(L) :- maplist(my_write, L), nl, length(L, N), length(LN, N), % there is a 0 before the beginning compute_next([0 |L], LN), ( L \= LN -> one_dimensional_cellular_automata(LN); true).

% All the possibilites compute_next([0, 0, 0 | R], [0 | R1]) :- compute_next([0, 0 | R], R1).

compute_next([0, 0, 1 | R], [0 | R1]) :- compute_next([0, 1 | R], R1).

compute_next([0, 1, 0 | R], [0 | R1]) :- compute_next([1, 0 | R], R1).

compute_next([0, 1, 1 | R], [1 | R1]) :- compute_next([1, 1 | R], R1).

compute_next([1, 0, 0 | R], [0 | R1]) :- compute_next([0, 0 | R], R1).

compute_next([1, 0, 1 | R], [1 | R1]) :- compute_next([0, 1 | R], R1).

compute_next([1, 1, 0 | R], [1 | R1]) :- compute_next([1, 0 | R], R1).

compute_next([1, 1, 1 | R], [0 | R1]) :- compute_next([1, 1 | R], R1).

% the last four possibilies => % we consider that there is à 0 after the end complang jq># The 1-d cellular automaton: def next:

  # Conveniently, jq treats null as 0 when it comes to addition
  # so there is no need to fiddle with the boundaries
 . as $old
 | reduce range(0; length) as $i
   ([];
    ($old[$i-1] + $old[$i+1]) as $s
    | if   $s == 0 then .[$i] = 0
      elif $s == 1 then .[$i] = (if $old[$i] == 1 then 1 else 0 end)
      else              .[$i] = (if $old[$i] == 1 then 0 else 1 end)
      end);


  1. pretty-print an array:

def pp: reduce .[] as $i (""; . + (if $i == 0 then " " else "*" end));

  1. continue until quiescence:

def go: recurse(. as $prev | next | if . == $prev then empty else . end) | pp;

  1. Example:

[0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0] | goute_next([0, 0], [0]).

compute_next([1, 0], [0]).

compute_next([0, 1], [0]).

compute_next([1, 1], [1]).

my_write(0) :- write(.).

my_write(1) :- write(#).

one_dimensional_cellular_automata :- L = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0], one_dimensional_cellular_automata(L). </lang>

Output:
 ?- one_dimensional_cellular_automata.
.###.##.#.#.#.#..#..
.#.#####.#.#.#......
..##...##.#.#.......
..##...###.#........
..##...#.##.........
..##....###.........
..##....#.#.........
..##.....#..........
..##................
true .

PureBasic

<lang PureBasic>EnableExplicit Dim cG.i(21) Dim nG.i(21) Define.i n, Gen

DataSection

 Data.i 0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0

EndDataSection For n=1 To 20

 Read.i cG(n)

Next

OpenConsole() Repeat

 Print("Generation "+Str(Gen)+": ")
 For n=1 To 20
   Print(Chr(95-cG(n)*60))
 Next
 Gen +1
 PrintN("")
 For n=1 To 20
   If (cG(n) And (cG(n-1) XOr cg(n+1))) Or (Not cG(n) And (cG(n-1) And cg(n+1)))
    nG(n)=1
  Else
    nG(n)=0   
  EndIf    
 Next 
 CopyArray(nG(), cG())

Until Gen > 9

PrintN("Press any key to exit"): Repeat: Until Inkey() <> ""</lang>

Output:
Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________

Python

Procedural

Python: Straightforward interpretation of spec

<lang python>import random

printdead, printlive = '_#' maxgenerations = 10 cellcount = 20 offendvalue = '0'

universe = .join(random.choice('01') for i in range(cellcount))

neighbours2newstate = {

'000': '0',
'001': '0',
'010': '0',
'011': '1',
'100': '0',
'101': '1',
'110': '1',
'111': '0',
}

for i in range(maxgenerations):

   print "Generation %3i:  %s" % ( i,
         universe.replace('0', printdead).replace('1', printlive) )
   universe = offendvalue + universe + offendvalue
   universe = .join(neighbours2newstate[universe[i:i+3]] for i in range(cellcount))</lang>
Output:
Generation   0:  _###_##_#_#_#_#__#__
Generation   1:  _#_#####_#_#_#______
Generation   2:  __##___##_#_#_______
Generation   3:  __##___###_#________
Generation   4:  __##___#_##_________
Generation   5:  __##____###_________
Generation   6:  __##____#_#_________
Generation   7:  __##_____#__________
Generation   8:  __##________________
Generation   9:  __##________________

Python: Using boolean operators on bits

The following implementation uses boolean operations to realize the function. <lang python>import random

nquads = 5 maxgenerations = 10 fmt = '%%0%ix'%nquads nbits = 4*nquads a = random.getrandbits(nbits) << 1

  1. a = int('01110110101010100100', 2) << 1

endmask = (2<<nbits)-2; endvals = 0<<(nbits+1) | 0 tr = ('____', '___#', '__#_', '__##', '_#__', '_#_#', '_##_', '_###',

     '#___', '#__#', '#_#_', '#_##', '##__', '##_#', '###_', '####' )

for i in range(maxgenerations):

  print "Generation %3i:  %s" % (i,(.join(tr[int(t,16)] for t in (fmt%(a>>1)))))
  a |= endvals
  a = ((a&((a<<1) | (a>>1))) ^ ((a<<1)&(a>>1))) & endmask</lang>

Python: Sum neighbours == 2

This example makes use of the observation that a cell is alive in the next generation if the sum with its current neighbours of alive cells is two. <lang python>>>> gen = [ch == '#' for ch in '_###_##_#_#_#_#__#__'] >>> for n in range(10): print(.join('#' if cell else '_' for cell in gen)) gen = [0] + gen + [0] gen = [sum(gen[m:m+3]) == 2 for m in range(len(gen)-2)]


_###_##_#_#_#_#__#__ _#_#####_#_#_#______ __##___##_#_#_______ __##___###_#________ __##___#_##_________ __##____###_________ __##____#_#_________ __##_____#__________ __##________________ __##________________ >>> </lang>

Composition of pure functions

Interpreting the rule shown in the task description as Wolfram rule 104, and generalising enough to allow for other rules of this kind: <lang python>Cellular Automata

from itertools import islice, repeat from functools import reduce from random import randint


  1. nextRowByRule :: Int -> [Bool] -> [Bool]

def nextRowByRule(intRule):

   A row of booleans derived by Wolfram rule n
      from another boolean row of the same length.
   
   # step :: (Bool, Bool, Bool) -> Bool
   def step(l, x, r):
       return bool(intRule & 2**intFromBools([l, x, r]))
   # go :: [Bool] -> [Bool]
   def go(xs):
       return [False] + list(map(
           step,
           xs, xs[1:], xs[2:]
       )) + [False]
   return go


  1. intFromBools :: [Bool] -> Int

def intFromBools(xs):

   Integer derived by binary interpretation
      of a list of booleans.
   
   def go(b, pn):
       power, n = pn
       return (2 * power, n + power if b else n)
   return foldr(go)([1, 0])(xs)[1]


  1. ------------------------- TEST -------------------------
  2. main :: IO ()

def main():

   Samples of Wolfram rule evolutions.
   
   print(
       unlines(map(showRuleSample, [104, 30, 110]))
   )


  1. ----------------------- DISPLAY ------------------------
  1. showRuleSample :: Int -> String

def showRuleSample(intRule):

   16 steps in the evolution
      of a given Wolfram rule.
   
   return 'Rule ' + str(intRule) + ':\n' + (
       unlines(map(
           showCells,
           take(16)(
               iterate(nextRowByRule(intRule))(
                   onePixelInLineOf(64) if (
                       bool(randint(0, 1))
                   ) else randomPixelsInLineOf(64)
               )
           )
       ))
   )


  1. boolsFromInt :: Int -> [Bool]

def boolsFromInt(n):

   List of booleans derived by binary
      decomposition of an integer.
   
   def go(x):
       return Just((x // 2, bool(x % 2))) if x else Nothing()
   return unfoldl(go)(n)


  1. nBoolsFromInt :: Int -> Int -> [Bool]

def nBoolsFromInt(n):

   List of bools, left-padded to given length n,
      derived by binary decomposition of an integer x.
   
   def go(n, x):
       bs = boolsFromInt(x)
       return list(repeat(False, n - len(bs))) + bs
   return lambda x: go(n, x)


  1. onePixelInLineOf :: Int -> [Bool]

def onePixelInLineOf(n):

   A row of n (mainly False) booleans,
      with a single True value in the middle.
   
   return nBoolsFromInt(n)(
       2**(n // 2)
   )


  1. randomPixelsInLineOf :: Int -> [Bool]

def randomPixelsInLineOf(n):

   A row of n booleans with pseudorandom values.
   
   return [bool(randint(0, 1)) for _ in range(1, 1 + n)]


  1. showCells :: [Bool] -> String

def showCells(xs):

   A block string representation of a list of booleans.
   
   return .join([chr(9608) if x else ' ' for x in xs])


  1. ----------------------- GENERIC ------------------------
  1. Just :: a -> Maybe a

def Just(x):

   Constructor for an inhabited Maybe (option type) value.
      Wrapper containing the result of a computation.
   
   return {'type': 'Maybe', 'Nothing': False, 'Just': x}


  1. Nothing :: () -> Maybe a

def Nothing():

   Constructor for an empty Maybe (option type) value.
      Empty wrapper returned where a computation is not possible.
   
   return {'type': 'Maybe', 'Nothing': True}


  1. foldr :: (a -> b -> b) -> b -> [a] -> b

def foldr(f):

   Right to left reduction of a list,
      using the binary operator f, and
      starting with an initial accumulator value.
   
   def g(a, x):
       return f(x, a)
   return lambda acc: lambda xs: reduce(
       g, xs[::-1], acc
   )


  1. iterate :: (a -> a) -> a -> Gen [a]

def iterate(f):

   An infinite list of repeated
      applications of f to x.
   
   def go(x):
       v = x
       while True:
           yield v
           v = f(v)
   return go


  1. take :: Int -> [a] -> [a]
  2. take :: Int -> String -> String

def take(n):

   The prefix of xs of length n,
      or xs itself if n > length xs.
   
   def go(xs):
       return (
           xs[0:n]
           if isinstance(xs, (list, tuple))
           else list(islice(xs, n))
       )
   return go


  1. unfoldl :: (b -> Maybe (b, a)) -> b -> [a]

def unfoldl(f):

   Dual to reduce or foldl.
      Where these reduce a list to a summary value, unfoldl
      builds a list from a seed value.
      Where f returns Just(a, b), a is appended to the list,
      and the residual b is used as the argument for the next
      application of f.
      When f returns Nothing, the completed list is returned.
   
   def go(v):
       x, r = v, v
       xs = []
       while True:
           mb = f(x)
           if mb.get('Nothing'):
               return xs
           else:
               x, r = mb.get('Just')
               xs.insert(0, r)
       return xs
   return go


  1. unlines :: [String] -> String

def unlines(xs):

   A single string formed by the intercalation
      of a list of strings with the newline character.
   
   return '\n'.join(xs)


  1. MAIN -------------------------------------------------

if __name__ == '__main__':

   main()</lang>
Output:
Rule 104:
    █  █  ████  ██    █   █      █ █ █ ██    █████ ██  ██  █ ██ 
          █  █  ██                █ █ ███    █   ████  ██   ███ 
                ██                 █ ██ █        █  █  ██   █ █ 
                ██                  ████               ██    █  
                ██                  █  █               ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
                ██                                     ██       
Rule 30:
                               █                                
                              ███                               
                             ██  █                              
                            ██ ████                             
                           ██  █   █                            
                          ██ ████ ███                           
                         ██  █    █  █                          
                        ██ ████  ██████                         
                       ██  █   ███     █                        
                      ██ ████ ██  █   ███                       
                     ██  █    █ ████ ██  █                      
                    ██ ████  ██ █    █ ████                     
                   ██  █   ███  ██  ██ █   █                    
                  ██ ████ ██  ███ ███  ██ ███                   
                 ██  █    █ ███   █  ███  █  █                  
                ██ ████  ██ █  █ █████  ███████                 
Rule 110:
█  █  ██ ██  ██  █ █  ██  ███ █ █ ███     ██ ██    █    █   █   
  ██ ██████ ███ ████ ███ ██ ███████ █    ██████   ██   ██  ██   
 █████    ███ ███  ███ ██████     ███   ██    █  ███  ███ ███   
 █   █   ██ ███ █ ██ ███    █    ██ █  ███   ██ ██ █ ██ ███ █   
 █  ██  █████ ████████ █   ██   █████ ██ █  █████████████ ███   
 █ ███ ██   ███      ███  ███  ██   ██████ ██           ███ █   
 ███ ████  ██ █     ██ █ ██ █ ███  ██    ████          ██ ███   
 █ ███  █ █████    ████████████ █ ███   ██  █         █████ █   
 ███ █ ████   █   ██          █████ █  ███ ██        ██   ███   
 █ █████  █  ██  ███         ██   ███ ██ ████       ███  ██ █   
 ███   █ ██ ███ ██ █        ███  ██ ██████  █      ██ █ █████   
 █ █  ███████ ██████       ██ █ █████    █ ██     ███████   █   
 ███ ██     ███    █      ███████   █   █████    ██     █  ██   
 █ ████    ██ █   ██     ██     █  ██  ██   █   ███    ██ ███   
 ███  █   █████  ███    ███    ██ ███ ███  ██  ██ █   █████ █   
 █ █ ██  ██   █ ██ █   ██ █   █████ ███ █ ███ █████  ██   ███   

Quackery

<lang Quackery> [ stack 0 ] is cells ( --> s )

[ dup size cells replace
  0 swap witheach 
    [ char # = 
      | 1 << ] ]                is setup    ( $ --> n )
[ 0 swap 
  cells share times 
    [ dup i >> 7 & 
      [ table 0 0 0 1 0 1 1 0 ]
      rot 1 << | swap ] 
  drop 1 << ]                   is nextline ( n --> n )
 [ cells share times
     [ dup i 1+ bit & 
       iff [ char # ]
       else [ char _ ] 
       emit ] 
   cr drop ]                    is echoline ( n -->   )
 [ setup
   [ dup echoline 
     dup nextline 
     tuck = until ]
   echoline ]                   is automate ( $ -->   )
 $ "_###_##_#_#_#_#__#__" automate</lang>
Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________


R

<lang R>set.seed(15797, kind="Mersenne-Twister")

maxgenerations = 10 cellcount = 20 offendvalue = FALSE

    1. Cells are alive if TRUE, dead if FALSE

universe <- c(offendvalue,

             sample( c(TRUE, FALSE), cellcount, replace=TRUE),
             offendvalue)
    1. List of patterns in which the cell stays alive

stayingAlive <- lapply(list(c(1,1,0),

                           c(1,0,1),
                           c(0,1,0)), as.logical)
    1. x : length 3 logical vector
    2. map: list of length 3 logical vectors that map to patterns
    3. in which x stays alive

deadOrAlive <- function(x, map) list(x) %in% map

cellularAutomata <- function(x, map) {

   c(x[1], apply(embed(x, 3), 1, deadOrAlive, map=map), x[length(x)])

}

deadOrAlive2string <- function(x) {

   paste(ifelse(x, '#', '_'), collapse="")

}

for (i in 1:maxgenerations) {

   universe <- cellularAutomata(universe, stayingAlive)
   cat(format(i, width=3), deadOrAlive2string(universe), "\n")

}</lang>

Output:
  1 _##_____####_#___#_#__ 
  2 _##_____#__##_____#___ 
  3 _##________##_________ 
  4 _##________##_________ 
  5 _##________##_________ 
  6 _##________##_________ 
  7 _##________##_________ 
  8 _##________##_________ 
  9 _##________##_________ 
 10 _##________##_________ 

Racket

<lang racket>#lang racket

(define (update cells)

 (for/list ([crowding (map +
                           (append '(0) (drop-right cells 1))
                           cells
                           (append (drop cells 1) '(0)))])
   (if (= 2 crowding) 1 0)))

(define (life-of cells time)

 (unless (zero? time)
   (displayln cells)
   (life-of (update cells) (sub1 time))))

(life-of '(0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0)

        10)
  1. | (0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0)
  (0 1 0 1 1 1 1 1 0 1 0 1 0 1 0 0 0 0 0 0)
  (0 0 1 1 0 0 0 1 1 0 1 0 1 0 0 0 0 0 0 0)
  (0 0 1 1 0 0 0 1 1 1 0 1 0 0 0 0 0 0 0 0)
  (0 0 1 1 0 0 0 1 0 1 1 0 0 0 0 0 0 0 0 0)
  (0 0 1 1 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0)
  (0 0 1 1 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0)
  (0 0 1 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0)
  (0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0)
  (0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0) |#</lang>

Below is an alternative implementation using graphical output in the Racket REPL. It works with DrRacket and Emacs + Geiser. <lang racket>#lang slideshow

Simulation of cellular automata, as described by Stephen Wolfram in his 1983 paper.
Uses Racket's inline image display capability for visual presentation

(require racket/draw) (require slideshow)

(define *rules* '((1 1 1) (1 1 0) (1 0 1) (1 0 0) (0 1 1) (0 1 0) (0 0 1) (0 0 0)))

(define (bordered-square n)

 (filled-rectangle n n #:draw-border? #t))

(define (draw-row lst)

 (apply hc-append 2 (map (λ (x) (colorize (bordered-square 10) (cond ((= x 0) "gray")

((= x 1) "red") (else "gray")))) lst)))

(define (extract-neighborhood nth prev-row)

 (take (drop (append '(0) prev-row '(0)) nth) 3))

(define (automaton-to-bits n)

 (reverse (map (λ (y) (if (zero? (bitwise-and y n)) 0 1)) 

(map (λ (x) (expt 2 x)) (range 0 8)))))

(define (get-rules bits)

 (map cdr (filter (λ (x) (= (car x) 1)) (map cons bits *rules*))))

(define (advance-row old-row rules)

 (let ([new '()])
   (for ([i (in-range 0 (length old-row))])
     (set! new (cons (if (member (extract-neighborhood i old-row)

rules) 1 0) new)))

   (reverse new)))

(define (draw-automaton automaton init-row row-number)

 (let* ([bit-representation (automaton-to-bits automaton)]

[rules (get-rules bit-representation)] [rows (list init-row)])

   (for ([i (in-range 1 row-number)])
     (set! rows (cons (advance-row (car rows) rules)

rows)))

   (apply vc-append 2 (map draw-row (reverse rows)))))

(draw-automaton 104 '(0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0) 10)</lang>

Raku

(formerly Perl 6)

Works with: rakudo version 2014-02-27

We'll make a general algorithm capable of computing any cellular automata as defined by Stephen Wolfram's famous book A new kind of Science. We will take the liberty of wrapping the array of cells as it does not affect the result much and it makes the implementation a lot easier.

<lang perl6>class Automaton {

   has $.rule;
   has @.cells;
   has @.code = $!rule.fmt('%08b').flip.comb».Int;

   method gist { "|{ @!cells.map({+$_ ?? '#' !! ' '}).join }|" }

   method succ {
       self.new: :$!rule, :@!code, :cells( 
           @!code[
                   4 «*« @!cells.rotate(-1)
               »+« 2 «*« @!cells
               »+«       @!cells.rotate(1)
           ]
       )
   }

}

  1. The rule proposed for this task is rule 0b01101000 = 104

my @padding = 0 xx 5; my Automaton $a .= new:

   rule  => 104,
   cells => flat @padding, '111011010101'.comb, @padding

say $a++ for ^10;


  1. Rule 104 is not particularly interesting so here is Rule 90,
  2. which shows a Sierpinski Triangle.

say ; @padding = 0 xx 25; $a = Automaton.new: :rule(90), :cells(flat @padding, 1, @padding);

say $a++ for ^20;</lang>

Output:
|     ### ## # # #     |
|     # ##### # #      |
|      ##   ## #       |
|      ##   ###        |
|      ##   # #        |
|      ##    #         |
|      ##              |
|      ##              |
|      ##              |
|      ##              |

|                         #                         |
|                        # #                        |
|                       #   #                       |
|                      # # # #                      |
|                     #       #                     |
|                    # #     # #                    |
|                   #   #   #   #                   |
|                  # # # # # # # #                  |
|                 #               #                 |
|                # #             # #                |
|               #   #           #   #               |
|              # # # #         # # # #              |
|             #       #       #       #             |
|            # #     # #     # #     # #            |
|           #   #   #   #   #   #   #   #           |
|          # # # # # # # # # # # # # # # #          |
|         #                               #         |
|        # #                             # #        |
|       #   #                           #   #       |
|      # # # #                         # # # #      |

Red

<lang Rebol>Red [

   Purpose: "One-dimensional cellular automata"
   Author: "Joe Smith"

]

vals: [0 1 0] kill: [[0 0] [#[none] 0] [0 #[none]]] evo: function [petri] [ new-petri: copy petri while [petri/1] [ if all [petri/-1 = 1 petri/2 = 1] [new-petri/1: select vals petri/1] if find/only kill reduce [petri/-1 petri/2] [new-petri/1: 0] petri: next petri new-petri: next new-petri ] petri: head petri new-petri: head new-petri clear insert petri new-petri ]

display: function [petri] [ print replace/all (replace/all to-string petri "0" "_") "1" "#" petri ]

loop 10 [ evo display [1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0] ] </lang>

Output:
###_##_#_#_#_#__#_
#_#####_#_#_#_____
_##___##_#_#______
_##___###_#_______
_##___#_##________
_##____###________
_##____#_#________
_##_____#_________
_##_______________
_##_______________

Retro

<lang Retro># 1D Cellular Automota

Assume an array of cells with an initial distribution of live and dead cells, and imaginary cells off the end of the array having fixed values.

Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbors in the current generation.

If, in the following table, a live cell is represented by 1 and a dead cell by 0 then to generate the value of the cell at a particular index in the array of cellular values you use the following table:

000 -> 0 # 001 -> 0 # 010 -> 0 # Dies without enough neighbours 011 -> 1 # Needs one neighbour to survive 100 -> 0 # 101 -> 1 # Two neighbours giving birth 110 -> 1 # Needs one neighbour to survive 111 -> 0 # Starved to death.

I had originally written an implementation of this in RETRO 11. For RETRO 12 I took advantage of new language features and some further considerations into the rules for this task.

The first word, `string,` inlines a string to `here`. I'll use this to setup the initial input.

~~~

string, (s-) [ , ] s:for-each #0 , ;

~~~

The next two lines setup an initial generation and a buffer for the evolved generation. In this case, `This` is the current generation and `Next` reflects the next step in the evolution.

~~~ 'This d:create

 '.###.##.#.#.#.#..#.. string, 

'Next d:create

 '.................... string, 

~~~

I use `display` to show the current generation.

~~~

display (-)
 &This s:put nl ; 

~~~

As might be expected, `update` copies the `Next` generation to the `This` generation, setting things up for the next cycle.

~~~

update (-)
 &Next &This dup s:length copy ; 

~~~

The word `group` extracts a group of three cells. This data will be passed to `evolve` for processing.

~~~

group (a-nnn)
 [ fetch ] 
 [ n:inc fetch ] 
 [ n:inc n:inc fetch ] tri ; 

~~~

I use `evolve` to decide how a cell should change, based on its initial state with relation to its neighbors.

In the prior implementation this part was much more complex as I tallied things up and had separate conditions for each combination. This time I take advantage of the fact that only cells with two neighbors will be alive in the next generation. So the process is:

- take the data from `group` - compare to `$#` (for living cells) - add the flags - if the result is `#-2`, the cell should live - otherwise it'll be dead

~~~

evolve (nnn-c)
 [ $# eq? ] tri@ + + 
 #-2 eq? [ $# ] [ $. ] choose ; 

~~~

For readability I separated out the next few things. `at` takes an index and returns the address in `This` starting with the index.

~~~

at (n-na)
 &This over + ; 

~~~

The `record` word adds the evolved value to a buffer. In this case my `generation` code will set the buffer to `Next`.

~~~

record (c-)
 buffer:add n:inc ; 

~~~

And now to tie it all together. Meet `generation`, the longest bit of code in this sample. It has several bits:

- setup a new buffer pointing to `Next`

 - this also preserves the old buffer

- setup a loop for each cell in `This`

 - initial loop index at -1, to ensure proper dummy state for first cell
 - get length of `This` generation

- perform a loop for each item in the generation, updating `Next` as it goes

- copy `Next` to `This` using `update`.

~~~

generation (-)
 [ &Next buffer:set 
   #-1 &This s:length 
   [ at group evolve record ] times drop 
   update 
 ] buffer:preserve ; 

~~~

The last bit is a helper. It takes a number of generations and displays the state, then runs a `generation`.

~~~

generations (n-)
 [ display generation ] times ; 

~~~

And a text. The output should be:

   .###.##.#.#.#.#..#..
   .#.#####.#.#.#......
   ..##...##.#.#.......
   ..##...###.#........
   ..##...#.##.........
   ..##....###.........
   ..##....#.#.........
   ..##.....#..........
   ..##................
   ..##................

~~~

  1. 10 generations

~~~</lang>

REXX

This REXX version will show (as a default)   40   generations,   or less if the generations of cellular automata repeat. <lang rexx>/*REXX program generates & displays N generations of one─dimensional cellular automata. */ parse arg $ gens . /*obtain optional arguments from the CL*/ if $== | $=="," then $=001110110101010 /*Not specified? Then use the default.*/ if gens== | gens=="," then gens=40 /* " " " " " " */

  do #=0  for gens                              /* process the  one-dimensional  cells.*/
  say  " generation"    right(#,length(gens))       ' '       translate($, "#·", 10)
  @=0                                                                /* [↓] generation.*/
         do j=2  for length($) - 1;          x=substr($, j-1, 3)     /*obtain the cell.*/
         if x==011 | x==101 | x==110  then @=overlay(1, @, j)        /*the cell lives. */
                                      else @=overlay(0, @, j)        /* "   "    dies. */
         end   /*j*/
  if $==@  then do;  say right('repeats', 40);  leave;  end          /*does it repeat? */
  $=@                                           /*now use the next generation of cells.*/
  end       /*#*/                               /*stick a fork in it,  we're all done. */</lang>

output when using the default input:

 generation  0   ··###·##·#·#·#·
 generation  1   ··#·#####·#·#··
 generation  2   ···##···##·#···
 generation  3   ···##···###····
 generation  4   ···##···#·#····
 generation  5   ···##····#·····
 generation  6   ···##··········
                                 repeats

Ring

<lang ring>

  1. Project : One-dimensional cellular automata

rule = ["0", "0", "0", "1", "0", "1", "1", "0"] now = "01110110101010100100"

for generation = 0 to 9

   see "generation " + generation + ": " + now + nl
   nxt = ""
   for cell = 1 to len(now)
       str = "bintodec(" + '"' +substr("0"+now+"0", cell, 3) + '"' + ")"
       eval("p=" + str) 
       nxt = nxt + rule[p+1]
   next 
   temp = nxt
   nxt = now
   now = temp

next

func bintodec(bin)

    binsum = 0
    for n=1  to len(bin)
        binsum = binsum + number(bin[n]) *pow(2, len(bin)-n)
    next
    return binsum

</lang> Output:

generation 0: 01110110101010100100
generation 1: 01011111010101000000
generation 2: 00110001101010000000
generation 3: 00110001110100000000
generation 4: 00110001011000000000
generation 5: 00110000111000000000
generation 6: 00110000101000000000
generation 7: 00110000010000000000
generation 8: 00110000000000000000
generation 9: 00110000000000000000

Ruby

<lang ruby>def evolve(ary)

 ([0]+ary+[0]).each_cons(3).map{|a,b,c| a+b+c == 2 ? 1 : 0}

end

def printit(ary)

 puts ary.join.tr("01",".#")

end

ary = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0] printit ary until ary == (new = evolve(ary))

 printit ary = new

end</lang>

Output:
.###.##.#.#.#.#..#..
.#.#####.#.#.#......
..##...##.#.#.......
..##...###.#........
..##...#.##.........
..##....###.........
..##....#.#.........
..##.....#..........
..##................

Rust

<lang rust>fn get_new_state(windowed: &[bool]) -> bool {

   match windowed {
       [false, true, true] | [true, true, false] => true,
       _ => false
   }

}

fn next_gen(cell: &mut [bool]) {

   let mut v = Vec::with_capacity(cell.len());
   v.push(cell[0]);
   for i in cell.windows(3) {
       v.push(get_new_state(i));
   }
   v.push(cell[cell.len() - 1]);
   cell.copy_from_slice(&v);

}

fn print_cell(cell: &[bool]) {

   for v in cell {
       print!("{} ", if *v {'#'} else {' '});
   }
   println!();

}

fn main() {

   const MAX_GENERATION: usize = 10;
   const CELLS_LENGTH: usize = 30;
   let mut cell: [bool; CELLS_LENGTH] = rand::random();
   for i in 1..=MAX_GENERATION {
       print!("Gen {:2}: ", i);
       print_cell(&cell);
       next_gen(&mut cell);
   }

} </lang>

Scala

Works with: Scala version 2.8

<lang scala>def cellularAutomata(s: String) = {

 def it = Iterator.iterate(s) ( generation =>
   ("_%s_" format generation).iterator 
   sliding 3 
   map (_ count (_ == '#')) 
   map Map(2 -> "#").withDefaultValue("_") 
   mkString
 )
 
 (it drop 1) zip it takeWhile Function.tupled(_ != _) map (_._2) foreach println

}</lang>

Sample:

scala> cellularAutomata("_###_##_#_#_#_#__#__")
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________

Scheme

Works with: Scheme version RRS

<lang scheme>(define (next-generation left petri-dish right)

 (if (null? petri-dish)
     (list)
     (cons (if (= (+ left
                     (car petri-dish)
                     (if (null? (cdr petri-dish))
                         right
                         (cadr petri-dish)))
                  2)
               1
               0)
           (next-generation (car petri-dish) (cdr petri-dish) right))))

(define (display-evolution petri-dish generations)

 (if (not (zero? generations))
     (begin (display petri-dish)
            (newline)
            (display-evolution (next-generation 0 petri-dish 0)
                               (- generations 1)))))

(display-evolution (list 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0) 10)</lang> Output:

(1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0)
(1 0 1 1 1 1 1 0 1 0 1 0 1 0 0 0 0 0)
(0 1 1 0 0 0 1 1 0 1 0 1 0 0 0 0 0 0)
(0 1 1 0 0 0 1 1 1 0 1 0 0 0 0 0 0 0)
(0 1 1 0 0 0 1 0 1 1 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0)

Seed7

A graphical cellular automaton can be found here.

<lang seed7>$ include "seed7_05.s7i";

const string: start is "_###_##_#_#_#_#__#__";

const proc: main is func

 local
   var string: g0 is start;
   var string: g1 is start;
   var integer: generation is 0;
   var integer: i is 0;
 begin
   writeln(g0);
   for generation range 0 to 9 do
     for i range 2 to pred(length(g0)) do
       if g0[i-1] <> g0[i+1] then
         g1 @:= [i] g0[i];
       elsif g0[i] = '_' then
         g1 @:= [i] g0[i-1];
       else
         g1 @:= [i] '_'
       end if;
     end for;
     writeln(g1);
     g0 := g1;
   end for;
 end func;</lang>

Output:

_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________

==Seed7==

A graphical cellular automaton can be found here.

> petriCache(i) Then stable = False

           If petriCache(i) Then dead = False
       Next
       PetriDish = petriCache
       If dead Then Return PetriStatus.Dead
       If stable Then Return PetriStatus.Stable
       Return PetriStatus.Active
   End Function
   Private Function BuildDishString(ByVal PetriDish As BitArray) As String
       Dim sw As New StringBuilder()
       For Each b As Boolean In PetriDish
           sw.Append(IIf(b, "#", "_"))
       Next
       Return sw.ToString()
   End Function

End Module

SequenceL

<lang sequencel>import <Utilities/Conversion.sl>;

main(args(2)) :=

   run(args[1], stringToInt(args[2])) when size(args) = 2 

else

   "Usage error: exec <initialCells> <generations>";

stringToCells(string(1))[i] := 0 when string[i] = '_' else 1; cellsToString(cells(1))[i] := '#' when cells[i] = 1 else '_';

run(cellsString(1), generations) :=

       runHelper(stringToCells(cellsString), generations, cellsString);

runHelper(cells(1), generations, result(1)) :=

   let
       nextCells := step(cells);
   in
       result when generations = 0
   else
       runHelper(nextCells, generations - 1, 
                 result ++ "\n" ++ cellsToString(nextCells));

step(cells(1))[i] :=

   let
       left := cells[i-1] when i > 1 else 0;
       right := cells[i + 1] when i < size(cells) else 0;
   in
       1 when (left + cells[i] + right) = 2
   else
       0;</lang>
Output:
"_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________"

Sidef

Translation of: Perl

<lang ruby>var seq = "_###_##_#_#_#_#__#__"; var x = ;

loop {

   seq.tr!('01', '_#');
   say seq;
   seq.tr!('_#', '01');
   seq.gsub!(/(?<=(.))(.)(?=(.))/, {|s1,s2,s3| s1 == s3 ? (s1 ? 1-s2 : 0) : s2});
   (x != seq) && (x = seq) || break;

}</lang>

Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
Translation of: Raku

<lang ruby>class Automaton(rule, cells) {

   method init {
       rule = sprintf("%08b", rule).chars.map{.to_i}.reverse;
   }
   method next {
       var previous = cells.map{_};
       var len = previous.len;
       cells[] = rule[
               previous.range.map { |i|
                   4*previous[i-1 % len] +
                   2*previous[i]         +
                     previous[i+1 % len]
               }...
           ]
   }
   method to_s {
       cells.map { _ ? '#' : ' ' }.join;
   }

}

var size = 10; var auto = Automaton(

   rule: 104,
   cells: [(size/2).of(0)..., 111011010101.digits..., (size/2).of(0)...],

);

size.times {

   say "|#{auto}|";
   auto.next;

}</lang>

Output:
|     ### ## # # #     |
|     # ##### # #      |
|      ##   ## #       |
|      ##   ###        |
|      ##   # #        |
|      ##    #         |
|      ##              |
|      ##              |
|      ##              |
|      ##              |

Tcl

<lang tcl>proc evolve {a} {

   set new [list]
   for {set i 0} {$i < [llength $a]} {incr i} {
       lappend new [fate $a $i]
   }
   return $new

}

proc fate {a i} {

   return [expr {[sum $a $i] == 2}]

}

proc sum {a i} {

   set sum 0
   set start [expr {$i - 1 < 0 ? 0 : $i - 1}]
   set end [expr {$i + 1 >= [llength $a] ? $i : $i + 1}]
   for {set j $start} {$j <= $end} {incr j} {
       incr sum [lindex $a $j]        
   }
   return $sum

}

proc print {a} {

   puts [string map {0 _ 1 #} [join $a ""]]

}

proc parse {s} {

   return [split [string map {_ 0 # 1} $s] ""]

}

set array [parse "_###_##_#_#_#_#__#__"] print $array while {[set new [evolve $array]] ne $array} {

   set array $new
   print $array

}</lang>

Ursala

Three functions are defined. Rule takes a neighborhood of three cells to the succeeding value of the middle one, step takes a list of cells to its successor by applying the rule across a sliding window, and evolve takes an initial list of cells to a list of those evolving from it according to the rule. The cells are maintained as a list of booleans (0 and &) but are converted to characters for presentation in the example code. <lang Ursala>#import std

  1. import nat

rule = -$<0,0,0,&,0,&,&,0>@rSS zipp0*ziD iota8

step = rule*+ swin3+ :/0+ --<0>

evolve "n" = @iNC ~&x+ rep"n" ^C/step@h ~&

  1. show+

example = ~&?(`#!,`.!)** evolve10 <0,&,&,&,0,&,&,0,&,0,&,0,&,0,0,&,0,0></lang> output:

.###.##.#.#.#..#..
.#.#####.#.#......
..##...##.#.......
..##...###........
..##...#.#........
..##....#.........
..##..............
..##..............
..##..............
..##..............
..##..............

Vedit macro language

This implementation writes the calculated patterns into an edit buffer, where the results can viewed and saved into a file if required. The edit buffer also acts as storage during calculations. <lang vedit>IT("Gen 0: ..###.##.#.#.#.#..#.....") // initial pattern

  1. 9 = Cur_Col

for (#8 = 1; #8 < 10; #8++) { // 10 generations

   Goto_Col(7)
   Reg_Empty(20)
   while (Cur_Col < #9-1) {
       if (Match("|{##|!#,#.#,|!###}")==0) {
           Reg_Set(20, "#", APPEND)
       } else {
           Reg_Set(20, ".", APPEND)
       }
       Char
   }
   EOL IN
   IT("Gen ") Num_Ins(#8, LEFT+NOCR) IT(": ")
   Reg_Ins(20)

}</lang>

Sample output: <lang vedit>Gen 0: ..###.##.#.#.#.#..#..... Gen 1: ..#.#####.#.#.#......... Gen 2: ...##...##.#.#.......... Gen 3: ...##...###.#........... Gen 4: ...##...#.##............ Gen 5: ...##....###............ Gen 6: ...##....#.#............ Gen 7: ...##.....#............. Gen 8: ...##................... Gen 9: ...##...................</lang>

Visual Basic .NET

This implementation is run from the command line. The command is followed by a string of either 1's or #'s for an active cell, or 0's or _'s for an inactive one.

<lang Visual Basic .NET>Imports System.Text

Module CellularAutomata

   Private Enum PetriStatus
       Active
       Stable
       Dead
   End Enum
   Function Main(ByVal cmdArgs() As String) As Integer
       If cmdArgs.Length = 0 Or cmdArgs.Length > 1 Then
           Console.WriteLine("Command requires string of either 1s and 0s or #s and _s.")
           Return 1
       End If
       Dim petriDish As BitArray
       Try
           petriDish = InitialisePetriDish(cmdArgs(0))
       Catch ex As Exception
           Console.WriteLine(ex.Message)
           Return 1
       End Try
       Dim generation As Integer = 0
       Dim ps As PetriStatus = PetriStatus.Active
       Do While True
           If ps = PetriStatus.Stable Then
               Console.WriteLine("Sample stable after {0} generations.", generation - 1)
               Exit Do
           Else
               Console.WriteLine("{0}: {1}", generation.ToString("D3"), BuildDishString(petriDish))
               If ps = PetriStatus.Dead Then
                   Console.WriteLine("Sample dead after {0} generations.", generation)
                   Exit Do
               End If
           End If
           ps = GetNextGeneration(petriDish)
           generation += 1
       Loop
       Return 0
   End Function
   Private Function InitialisePetriDish(ByVal Sample As String) As BitArray
       Dim PetriDish As New BitArray(Sample.Length)
       Dim dead As Boolean = True
       For i As Integer = 0 To Sample.Length - 1
           Select Case Sample.Substring(i, 1)
               Case "1", "#"
                   PetriDish(i) = True
                   dead = False
               Case "0", "_"
                   PetriDish(i) = False
               Case Else
                   Throw New Exception("Illegal value in string position " & i)
                   Return Nothing
           End Select
       Next
       If dead Then
           Throw New Exception("Entered sample is dead.")
           Return Nothing
       End If
       Return PetriDish
   End Function
   Private Function GetNextGeneration(ByRef PetriDish As BitArray) As PetriStatus
       Dim petriCache = New BitArray(PetriDish.Length)
       Dim neighbours As Integer
       Dim stable As Boolean = True
       Dim dead As Boolean = True
       For i As Integer = 0 To PetriDish.Length - 1
           neighbours = 0
           If i > 0 AndAlso PetriDish(i - 1) Then neighbours += 1
           If i < PetriDish.Length - 1 AndAlso PetriDish(i + 1) Then neighbours += 1
           petriCache(i) = (PetriDish(i) And neighbours = 1) OrElse (Not PetriDish(i) And neighbours = 2)
           If PetriDish(i) <> petriCache(i) Then stable = False
           If petriCache(i) Then dead = False
       Next
       PetriDish = petriCache
       If dead Then Return PetriStatus.Dead
       If stable Then Return PetriStatus.Stable
       Return PetriStatus.Active
   End Function
   Private Function BuildDishString(ByVal PetriDish As BitArray) As String
       Dim sw As New StringBuilder()
       For Each b As Boolean In PetriDish
           sw.Append(IIf(b, "#", "_"))
       Next
       Return sw.ToString()
   End Function

End Module</lang>

Output:

C:\>CellularAutomata _###_##_#_#_#_#__#__
000: _###_##_#_#_#_#__#__
001: _#_#####_#_#_#______
002: __##___##_#_#_______
003: __##___###_#________
004: __##___#_##_________
005: __##____###_________
006: __##____#_#_________
007: __##_____#__________
008: __##________________
Sample stable after 8 generations.

Wart

Simple

<lang python>def (gens n l)

 prn l
 repeat n
   zap! gen l
   prn l

def (gen l)

 with (a nil  b nil  c l.0)
   collect nil  # won't insert paren without second token
     each x cdr.l
       shift! a b c x
       yield (next a b c)
     yield (next b c nil)

def (next a b c) # next state of b given neighbors a and c

 if (and a c)  not.b
    (or a c)  b</lang>

Output looks a little ugly:

ready! type in an expression, then hit enter twice. ctrl-d exits.
gens 5 '(1 1 1 nil 1)

(1 1 1 nil 1)
(1 nil 1 1 nil)
(nil 1 1 1 nil)
(nil 1 nil 1 nil)
(nil nil 1 nil nil)
(nil nil nil nil nil)

More sophisticated

Computing the next generation becomes much cleaner once you invest a few LoC in a new datatype.

<lang python>def (uca l) # new datatype: Uni-dimensional Cellular Automaton

 (tag uca (list l len.l))

def (len l) :case (isa uca l) # how to compute its length

 rep.l.1

defcoerce uca list # how to convert it to a list

 (fn(_) rep._.0)

def (pr l) :case (isa uca l) # how to print it

 each x l  # transparently coerces to a list for iterating over
   pr (if x "#" "_")
  1. (l i) returns ith cell when l is a uca, and nil when i is out-of-bounds

defcall uca (l i)

 if (0 <= i < len.l)
   rep.l.0.i

def (gens n l)

 prn l
 repeat n
   zap! gen l
   prn l

def (gen l)

 uca+collect+for i 0 (i < len.l) ++i
   yield (next  (l i-1)  l.i  (l i+1))
  1. next state of b, given neighbors a and c

def (next a b c)

 if (and a c) not.b
    (or a c)  b</lang>

Output is prettier now:

ready! type in an expression, then hit enter twice. ctrl-d exits.
gens 10 (uca '(nil 1 1 1 nil 1 1 nil 1 nil 1 nil 1 nil 1 nil nil 1 nil nil))

_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________

Wren

Translation of: Kotlin

<lang ecmascript>var trans = "___#_##_"

var v = Fn.new { |cell, i| (cell[i] != "_") ? 1 : 0 }

var evolve = Fn.new { |cell, backup|

   var len = cell.count - 2
   var diff = 0
   for (i in 1...len) {
       /* use left, self, right as binary number bits for table index */
       backup[i] = trans[v.call(cell, i - 1) * 4 + v.call(cell, i) * 2 + v.call(cell, i + 1)]
       diff = diff + ((backup[i] != cell[i]) ? 1 : 0)
   }
   cell.clear()
   cell.addAll(backup)
   return diff != 0

}

var c = "_###_##_#_#_#_#__#__".toList var b = "____________________".toList while(true) {

   System.print(c[1..-1].join())
   if (!evolve.call(c,b)) break

}</lang>

Output:
###_##_#_#_#_#__#__
#_#####_#_#_#______
_##___##_#_#_______
_##___###_#________
_##___#_##_________
_##____###_________
_##____#_#_________
_##_____#__________
_##________________

XPL0

<lang XPL0>code ChOut=8, CrLf=9; int Gen, Now, New, I; [Now:= $076A_A400; for Gen:= 1 to 10 do

   [for I:= 31 downto 0 do ChOut(0, if Now & 1<>(I-1) & 7 of %011, %101, %110: New:= New ! 1<<I other;
   Now:= New;
   ];

]</lang>

Output:
_____###_##_#_#_#_#__#__________
_____#_#####_#_#_#______________
______##___##_#_#_______________
______##___###_#________________
______##___#_##_________________
______##____###_________________
______##____#_#_________________
______##_____#__________________
______##________________________
______##________________________

Yabasic

Translation of: Locomotive_Basic

<lang Yabasic>10 n=10:READ w:DIM x(w+1),x2(w+1):FOR i=1 to w:READ x(i):NEXT 20 FOR k=1 TO n 30 FOR j=1 TO w 40 IF x(j) THEN PRINT "#"; ELSE PRINT "_"; END IF 50 IF x(j-1)+x(j)+x(j+1)=2 THEN x2(j)=1 ELSE x2(j)=0 END IF 60 NEXT:PRINT 70 FOR j=1 TO w:x(j)=x2(j):NEXT 80 NEXT 90 DATA 20,0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0</lang>

Other solution <lang Yabasic>start$ = "0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0"

dim x$(1)

for k = 1 to 10

   n = token(start$, x$(), ",")
   redim x$(n+1)
   start$ = ""
   for j = 1 to n
       if val(x$(j)) then print "#"; else print "_"; end if
       test = abs(val(x$(j-1)) + val(x$(j)) + val(x$(j+1)) = 2)
       start$ = start$ + str$(test) + ","
   next j
   print

next k</lang>

zkl

Translation of: Groovy

<lang zkl>fcn life1D(line){

  right:=line[1,*] + False;           // shift left, False fill
  left :=T(False).extend(line[0,-1]); // shift right
  left.zip(line,right).apply(fcn(hood){ hood.sum(0)==2 });

}</lang> <lang zkl>chars:=T("_","#"); cells:="_###_##_#_#_#_#__#__".split("").apply('==("#")); //-->L(False,True,True,True,False...) do(10){ cells.apply(chars.get).concat().println(); cells=life1D(cells); }</lang> Or, using strings instead of lists: <lang zkl>fcn life1D(line){

  right:=line[1,*] + "_";  // shift left, "_" fill
  left :="_" + line[0,-1]; // shift right
  Utils.Helpers.zipWith(
     fcn(a,b,c){ (String(a,b,c) - "_") == "##" and "#" or "_" },
     left,line,right).concat();

}</lang> <lang zkl>cells:="_###_##_#_#_#_#__#__"; do(10){ cells.println(); cells=life1D(cells); }</lang>

Output:
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
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/pre>