One-dimensional cellular automata: Difference between revisions

This REXX version will show (as a default)   40   generations,   or less if the generations of cellular automata repeat.

<lang rexx>/*REXX program displaysgenerates & displays N generations of one-dimensionalone─dimensional cellular automata. */

parse arg $ gens .; if $=='' | $==',' then $=001110110101010 /*useobtain optional arguments from the default?CL*/

if if gens$=='' | $=="," then gens$=40 001110110101010 /*Not "specified? Then use the " default.*/

if gens=='' | gens=="," then gens=40 /* " L=length($)-1 " " " " " /*adjusted len*/

do #=0 for gens /* process the one-dimensional /*process genscells.*/

say " generation" right(#,length(gens)) ' ' translate($, "#·", 10)

@=0 do j=2 for L; x=substr($,j-1,3) /*obtain cell[↓] generation.*/

if x=do j=0112 | x==101for |length($) x==110- 1; then @ x=overlaysubstr(1,@$, j-1, 3) /*cellobtain lives.the cell.*/

if x==011 | x==101 | x==110 elsethen @=overlay(01, @, j) /*the cell deathlives. */

if $==@ then do; say right('repeats',40); leave; end /*it repeats? j*/

$=@ /*stick a fork in it, we're all/*now done.use the next generation of cells.*/</lang>