Sum of squares

From Rosetta Code
Task
Sum of squares
You are encouraged to solve this task according to the task description, using any language you may know.
Task

Write a program to find the sum of squares of a numeric vector.

The program should work on a zero-length vector (with an answer of   0).


Related task



0815[edit]

{x{*%<:d:~$<:1:~>><:2:~>><:3:~>><:4:~>><:5:~>><:6:~>><:7:
~>><:8:~>><:9:~>><:a:~>><:b:~>><:c:~>><:ffffffffffffffff:
~>{x{*>}:8f:{x{*&{=+>{~>&=x<:ffffffffffffffff:/#:8f:{{~%
Output:
0
28A

11l[edit]

print(sum([1, 2, 3, 4, 5].map(x -> x^2)))
Output:
55

360 Assembly[edit]

*        Sum of squares            27/08/2015
SUMOFSQR CSECT
         USING  SUMOFSQR,R12
         LR     R12,R15
         LA     R7,A               a(1)
         SR     R6,R6              sum=0
         LA     R3,1               i=1
LOOPI    CH     R3,N               do i=1 to hbound(a)
         BH     ELOOPI
         L      R5,0(R7)           a(i)
         M      R4,0(R7)           a(i)*a(i)
         AR     R6,R5              sum=sum+a(i)**2
         LA     R7,4(R7)           next a
         LA     R3,1(R3)           i=i+1
         B      LOOPI              end i
ELOOPI   XDECO  R6,PG+23           edit sum
         XPRNT  PG,80
         XR     R15,R15
         BR     R14
A        DC     F'1',F'2',F'3',F'4',F'5',F'6',F'7',F'8',F'9',F'10'
PG       DC     CL80'The sum of squares is: '
N        DC     AL2((PG-A)/4)
         YREGS
         END    SUMOFSQR
Output:
The sum of squares is:          385

8086 Assembly[edit]

		;;; Sum of squares
		cpu	8086
		bits	16
section		.text
		org	100h
		jmp	demo
		;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		;;; Calculate the sum of the squares of the array in SI.
		;;; The array should contain 16-bit unsigned integers.
		;;; The output will be 32-bit.
		;;; Input: (DS:)SI = array, CX = array length
		;;; Output: DX:AX = sum of squares
		;;; Registers used: AX,BX,CX,DX,SI,DI
sumsqr:		xor	bx,bx	; Keep accumulator in BX:DI.
		xor	di,di	; (So zero it out first)
		and	cx,cx	; Counter register 0? "Program should work
		jz	.done	; on a zero-length vector"
.loop:		mov	ax,[si]	; Grab value from array
		mul	ax	; Calculate square of value (into DX:AX)
		add	di,ax	; Add low 16 bits to accumulator
		adc	bx,dx	; Add high 16 bits, plus carry
		inc	si	; Point to next value
		inc	si
		loop	.loop	; Next value in array
.done:		mov	ax,di	; Return the value in DX:AX as is tradition
		mov	dx,bx
		ret
		;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		;;; Demo: use the subroutine to calculate the sum of squares
		;;; in the included array, and show the result
demo:		mov	si,array
		mov	cx,arrlen
		call	sumsqr
		;;; Print the return value in DX:AX as a decimal number
		;;; (Note: max supported value 655359 - this is a limitation
		;;; of this rudimentary output code, not of the sum of squares
		;;; routine.)
		mov	di,outstr_end
		mov	cx,10
.decloop:	div	cx
		dec	di
		add	dl,'0'
		mov	[di],dl
		xor	dx,dx
		and	ax,ax
		jnz	.decloop
		mov	dx,di
		mov	ah,9
		int	21h
		ret
section		.data
outstr:		db	'######'	; Placeholder for decimal output 
outstr_end:	db	'$'
array:		dw	1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20
arrlen:		equ	($-array)/2	; length is in words

ACL2[edit]

(defun sum-of-squares (xs)
   (if (endp xs)
       0
       (+ (* (first xs) (first xs))
          (sum-of-squares (rest xs)))))

Action![edit]

CARD FUNC SumOfSqr(BYTE ARRAY a BYTE count)
  BYTE i
  CARD res

  IF count=0 THEN
    RETURN (0)
  FI

  res=0
  FOR i=0 TO count-1
  DO
    res==+a(i)*a(i)
  OD
RETURN (res)

PROC Test(BYTE ARRAY a BYTE count)
  BYTE i
  CARD res

  res=SumOfSqr(a,count)
  Print("[")
  IF count>0 THEN
    FOR i=0 to count-1
    DO
      PrintB(a(i))
      IF i<count-1 THEN
        Put(' )
      FI
    OD
  FI
  PrintF("]->%U%E%E",res)
RETURN

PROC Main()
  BYTE ARRAY a=[1 2 3 4 5]
  BYTE ARRAY b=[10 20 30 40 50 60 70 80 90]
  BYTE ARRAY c=[11]
  
  Test(a,5)
  Test(b,9)
  Test(c,1)
  Test(c,0)
RETURN
Output:

Screenshot from Atari 8-bit computer

[1 2 3 4 5]->55

[10 20 30 40 50 60 70 80 90]->28500

[11]->121

[]->0

ActionScript[edit]

function sumOfSquares(vector:Vector.<Number>):Number
{
	var sum:Number = 0;
	for(var i:uint = 0; i < vector.length; i++)
		sum += vector[i]*vector[i];
	return sum;
}

Ada[edit]

with Ada.Text_IO;  use Ada.Text_IO;

procedure Test_Sum_Of_Squares is
   type Float_Array is array (Integer range <>) of Float;

   function Sum_Of_Squares (X : Float_Array) return Float is
      Sum : Float := 0.0;
   begin
      for I in X'Range loop
         Sum := Sum + X (I) ** 2;
      end loop;
      return Sum;
   end Sum_Of_Squares;
   
begin
   Put_Line (Float'Image (Sum_Of_Squares ((1..0 => 1.0)))); -- Empty array
   Put_Line (Float'Image (Sum_Of_Squares ((3.0, 1.0, 4.0, 1.0, 5.0, 9.0))));
end Test_Sum_Of_Squares;
Output:
 0.00000E+00
 1.33000E+02

Aime[edit]

real
squaredsum(list l)
{
    integer i;
    real s;

    s = 0;
    i = -~l;
    while (i) {
        s += sq(l[i += 1]);
    }

    s;
}

integer
main(void)
{
    list l;

    l = list(0, 1, 2, 3);

    o_form("~\n", squaredsum(l));
    o_form("~\n", squaredsum(list()));
    o_form("~\n", squaredsum(list(.5, -.5, 2)));

    0;
}
Output:
14
0
4.5

ALGOL 68[edit]

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
Works with: ELLA ALGOL 68 version Any (with appropriate job cards) - tested with release 1.8-8d

The computation can be written as a loop.

PROC sum of squares = ([]REAL argv)REAL:(
  REAL sum := 0;
  FOR i FROM LWB argv TO UPB argv DO
    sum +:= argv[i]**2
  OD;
  sum
);
test:(
  printf(($g(0)l$,sum of squares([]REAL(3, 1, 4, 1, 5, 9))));
)
Output:
133

Another implementation could define a procedure (proc) or operator (op) called map.

Translation of: python
[]REAL data = (3, 1, 4, 1, 5, 9);

PROC map = ( PROC(REAL)REAL func, []REAL argv)REAL:
    ( REAL out:=0; FOR i FROM LWB argv TO UPB argv DO out:=func(argv[i]) OD; out);

test:(
  REAL sum := 0;
  printf(($xg(0)l$, map ( ((REAL argv)REAL: sum +:= argv ** 2), data) ));

  PRIO MAP = 5; # the same priority as the operators <, =<, >=, & > maybe... #
  OP MAP = ( PROC(REAL)REAL func, []REAL argv)REAL:
    ( REAL out:=0; FOR i FROM LWB argv TO UPB argv DO out:=func(argv[i]) OD; out);

  sum := 0;
  printf(($g(0)l$, ((REAL argv)REAL: sum +:= argv ** 2) MAP data ))
)
Output:
133
133
Works with: ALGOL 68 version Revision 1 - requires the Currying extension
Works with: ALGOL 68G version Any - tested with release a68g-2.8.3


The computation can be written as a generator.

#!/usr/bin/a68g --script #
# -*- coding: utf-8 -*- #

MODE YIELDREAL = PROC(REAL)VOID;
MODE GENREAL = PROC(YIELDREAL)VOID;

PROC gen real of vector = ([]REAL data, YIELDREAL yield)VOID:
  FOR i FROM LWB data TO UPB data DO yield(data[i]) OD;

PROC real sum sq of gen = (GENREAL gen real)REAL: (
  REAL sum:=0;
# FOR REAL value IN # gen real(#) DO (#
     (REAL value)VOID:(
       sum+:=value**2
# OD #));
  sum
);

PROC real sum map of gen = (PROC(REAL)REAL func, GENREAL gen real)REAL: (
  REAL sum:=0;
# FOR REAL value IN # gen real(#) DO (#
     (REAL value)VOID:(
       sum+:=func(value)
# OD #));
  sum
);

OP GEN = ([]REAL array)GENREAL:gen real of vector(array,);

OP (GENREAL #gen real#)REAL SUMSQ = real sum sq of gen;

PRIO SUMMAP = 5;
OP (PROC(REAL)REAL #func#, GENREAL #gen real#)REAL SUMMAP = real sum map of gen;

test:(
  []REAL data = (3, 1, 4, 1, 5, 9);
# Permutations of the above routines #
  printf(($"real sum sq GEN: "g(0)l$, real sum sq of gen(GEN data)));
  printf(($"real sum sq real gen: "g(0)l$, real sum sq of gen(gen real of vector(data,))));
  printf(($"real sum map real gen: "g(0)l$, real sum map of gen(((REAL x)REAL: x*x),gen real of vector(data,))));
  printf(($"SUMSQ real gen: "g(0)l$, SUMSQ gen real of vector(data,)));
  printf(($"SUMSQ GEN: "g(0)l$, SUMSQ GEN data));
  printf(($"sq SUMMAP GEN: "g(0)l$, ((REAL x)REAL: x*x)SUMMAP GEN data))
)
Output:
real sum sq GEN: 133
real sum sq real gen: 133
real sum map real gen: 133
SUMSQ real gen: 133
SUMSQ GEN: 133
sq SUMMAP GEN: 133

ALGOL W[edit]

begin
    % procedure to sum the elements of a vector. As the procedure can't find %
    % the bounds of the array for itself, we pass them in lb and ub          %
    real procedure sumSquares ( real    array vector ( * )
                              ; integer value lb
                              ; integer value ub
                              ) ;
    begin
        real sum;
        sum := 0;
        for i := lb until ub do sum := sum + ( vector( i ) * vector( i ) );
        sum
    end sumOfSquares ;

    % test the sumSquares procedure                                          %
    real array numbers ( 1 :: 5 );
    for i := 1 until 5 do numbers( i ) := i;
    r_format := "A"; r_w := 10; r_d := 1; % set fixed point output           %
    write( sumSquares( numbers, 1, 5 ) );
end.

Alore[edit]

def sum_squares(a)
   var sum = 0
   for i in a
      sum = sum + i**2
   end
   return sum
end

WriteLn(sum_squares([3,1,4,1,5,9]))
end

APL[edit]

      square_sum{+/*2}
      square_sum 1 2 3 4 5
55
      square_sum  ⍝The empty vector
0

AppleScript[edit]

Two ways of composing a sumOfSquares function:

------ TWO APPROACHES – SUM OVER MAP, AND DIRECT FOLD ----

-- sumOfSquares :: Num a => [a] -> a
on sumOfSquares(xs)
    script squared
        on |λ|(x)
            x ^ 2
        end |λ|
    end script
    
    sum(map(squared, xs))
end sumOfSquares


-- sumOfSquares2 :: Num a => [a] -> a
on sumOfSquares2(xs)
    script plusSquare
        on |λ|(a, x)
            a + x ^ 2
        end |λ|
    end script
    
    foldl(plusSquare, 0, xs)
end sumOfSquares2


--------------------------- TEST -------------------------
on run
    set xs to [3, 1, 4, 1, 5, 9]
    
    {sumOfSquares(xs), sumOfSquares2(xs)}
    
    -- {133.0, 133.0}
end run


-------------------- GENERIC FUNCTIONS -------------------

-- foldl :: (a -> b -> a) -> a -> [b] -> a
on foldl(f, startValue, xs)
    tell mReturn(f)
        set v to startValue
        set lng to length of xs
        repeat with i from 1 to lng
            set v to |λ|(v, item i of xs, i, xs)
        end repeat
        return v
    end tell
end foldl


-- map :: (a -> b) -> [a] -> [b]
on map(f, xs)
    tell mReturn(f)
        set lng to length of xs
        set lst to {}
        repeat with i from 1 to lng
            set end of lst to |λ|(item i of xs, i, xs)
        end repeat
        return lst
    end tell
end map


-- Lift 2nd class handler function into 1st class script wrapper 
-- mReturn :: Handler -> Script
on mReturn(f)
    if class of f is script then
        f
    else
        script
            property |λ| : f
        end script
    end if
end mReturn


-- sum :: Num a => [a] -> a
on sum(xs)
    script add
        on |λ|(a, b)
            a + b
        end |λ|
    end script
    
    foldl(add, 0, xs)
end sum
Output:
{133.0, 133.0}

Arturo[edit]

arr: 1..10

print sum map arr [x][x^2]
Output:
385

Astro[edit]

sum([1, 2, 3, 4]²)

Asymptote[edit]

int suma;
int[] a={1, 2, 3, 4, 5, 6};
  
for(var i : a)
    suma = suma + a[i] ^ 2;

write("The sum of squares is: ", suma);

AutoHotkey[edit]

list = 3 1 4 1 5 9
Loop, Parse, list, %A_Space%
 sum += A_LoopField**2
MsgBox,% sum

AWK[edit]

Vectors are read, space-separated, from stdin; sum of squares goes to stdout. The empty line produces 0.

$ awk '{s=0;for(i=1;i<=NF;i++)s+=$i*$i;print s}'
3 1 4 1 5 9
133

0

BASIC[edit]

Works with: QBasic

Assume the numbers are in an array called a.

sum = 0
FOR I = LBOUND(a) TO UBOUND(a)
  sum = sum + a(I) ^ 2
NEXT I
PRINT "The sum of squares is: " + sum

BaCon[edit]

' Sum of squares
FUNCTION ss(int arr[], NUMBER elem)
    sum = 0
    FOR i = 0 TO elem - 1
        sum = sum + POW(arr[i], 2)
    NEXT
    RETURN sum
END FUNCTION

' 1 to 10 in the test vector, or 1 to -s n
option = CMDLINE("s:")
IF option = ASC("s") THEN
    elem = VAL(ARGUMENT$)
ELSE
    elem = 10
END IF

DECLARE vector TYPE int ARRAY elem
FOR i = 0 TO elem - 1
    vector[i] = i + 1
NEXT
PRINT ss(vector, elem)
Output:
prompt$ ./sumsquares
385
prompt$ ./sumsquares -s 1000
333833500

BASIC256[edit]

arraybase 1

dim a(6)
a[1] = 1.0
a[2] = 2.0
a[3] = 3.0
a[4] = -1.0
a[5] = -2.0
a[6] = -3.0

sum = 0
for i = 1 to a[?]
	sum += a[i] ^ 2
next i
print "The sum of squares is: "; sum
end

BBC BASIC[edit]

BBC BASIC cannot have a zero-length array.

      DIM vector(5)
      vector() = 1, 2, 3, 4, 5, 6
      
      PRINT "Sum of squares = " ; MOD(vector()) ^ 2
Output:
Sum of squares = 91

IS-BASIC[edit]

100 INPUT PROMPT "Number of elements: ":N
110 NUMERIC A(1 TO N)
120 FOR I=1 TO N
130   PRINT I;:INPUT PROMPT ". = ":A(I)
140 NEXT
150 PRINT "The sum of squares is:";SQ(A)
160 DEF SQ(REF T)
170   LET S=0
180   FOR I=LBOUND(T) TO UBOUND(T)
190     LET S=S+T(I)^2
200   NEXT
210   LET SQ=S
220 END DEF

Yabasic[edit]

data 1.0, 2.0, 3.0, -1.0, -2.0, -3.0
dim a(5)
sum = 0

for i = 0 to arraysize(a(), 1)
    read a(i)
    sum = sum + a(i) ^ 2
next i
print "The sum of squares is: ", sum
end

bc[edit]

define s(a[], n) {
    auto i, s
    
    for (i = 0; i < n; i++) {
        s += a[i] * a[i]
    }
    
    return(s)
}

BCPL[edit]

get "libhdr"

let sumsquares(v, len) =
    len=0 -> 0,
    !v * !v + sumsquares(v+1, len-1)
    
let start() be
$(  let vector = table 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
    writef("%N*N", sumsquares(vector, 10))
$)
Output:
385

BQN[edit]

Similar to the BQN entry in Sum of a series.

SSq ← +´√⁼

•Show SSq 1‿2‿3‿4‿5
•Show SSq ⟨⟩
55
0

Bracmat[edit]

( ( sumOfSquares
  =   sum component
    .   0:?sum
      &   whl
        ' ( !arg:%?component ?arg
          & !component^2+!sum:?sum
          )
      & !sum
  )
& out$(sumOfSquares$(3 4))
& out$(sumOfSquares$(3 4 i*5))
& out$(sumOfSquares$(a b c))
);
Output:
25
0
a^2+b^2+c^2

Brat[edit]

p 1.to(10).reduce 0 { res, n | res = res + n ^ 2 }  #Prints 385

C[edit]

#include <stdio.h>

double squaredsum(double *l, int e)
{
   int i; double sum = 0.0;
   for(i = 0 ; i < e ; i++) sum += l[i]*l[i];
   return sum;
}

int main()
{
   double list[6] = {3.0, 1.0, 4.0, 1.0, 5.0, 9.0};
   
   printf("%lf\n", squaredsum(list, 6));
   printf("%lf\n", squaredsum(list, 0));
   /* the same without using a real list as if it were 0-element long */
   printf("%lf\n", squaredsum(NULL, 0));
   return 0;
}

C#[edit]

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static int SumOfSquares(IEnumerable<int> list)
    {
        return list.Sum(x => x * x);
    }
    static void Main(string[] args)
    {
        Console.WriteLine(SumOfSquares(new int[] { 4, 8, 15, 16, 23, 42 })); // 2854
        Console.WriteLine(SumOfSquares(new int[] { 1, 2, 3, 4, 5 })); // 55
        Console.WriteLine(SumOfSquares(new int[] { })); // 0
    }
}

C++[edit]

Using accumulate[edit]

#include <iostream>
#include <numeric>
#include <vector>

double add_square(double prev_sum, double new_val)
{
  return prev_sum + new_val*new_val;
}

double vec_add_squares(std::vector<double>& v)
{
  return std::accumulate(v.begin(), v.end(), 0.0, add_square);
}

int main()
{
  // first, show that for empty vectors we indeed get 0
  std::vector<double> v; // empty
  std::cout << vec_add_squares(v) << std::endl;

  // now, use some values
  double data[] = { 0, 1, 3, 1.5, 42, 0.1, -4 };
  v.assign(data, data+7);
  std::cout << vec_add_squares(v) << std::endl;
  return 0;
}

Using inner_product[edit]

#include <iostream>
#include <numeric>
#include <vector>

int main()
{
  // first, show that for empty vectors we indeed get 0
  std::vector<double> v; // empty
  std::cout << std::inner_product(begin(v), end(v), begin(v), 0.0) << std::endl;
  
  // now, use some values
  double data[] = { 0, 1, 3, 1.5, 42, 0.1, -4 };
  v.assign(data, data+7);
  std::cout << std::inner_product(begin(v), end(v), begin(v), 0.0) << std::endl;
  return 0;
}

Using Boost.Lambda[edit]

Library: Boost.Lambda
#include <numeric>
#include <vector>
#include "boost/lambda/lambda.hpp"

double vec_add_squares(std::vector<double>& v)
{
  using namespace boost::lambda;

  return std::accumulate(v.begin(), v.end(), 0.0, _1 + _2 * _2);
}

Chef[edit]

Sum of squares.

First input is length of vector, then rest of input is vector.

Ingredients.
1 g eggs
0 g bacon

Method.
Put bacon into the 1st mixing bowl.
Take eggs from refrigerator.
Square the eggs.
Take bacon from refrigerator.
Put bacon into 2nd mixing bowl.
Combine bacon into 2nd mixing bowl.
Fold bacon into 2nd mixing bowl.
Add the bacon into the 1st mixing bowl.
Ask the eggs until squared.
Pour contents of the 1st mixing bowl into the 1st baking dish.

Serves 1.

Clojure[edit]

(defn sum-of-squares [v]
  (reduce #(+ %1 (* %2 %2)) 0 v))

CLU[edit]

sum_squares = proc (ns: sequence[int]) returns (int)
    sum: int := 0
    for n: int in sequence[int]$elements(ns) do
        sum := sum + n ** 2
    end
    return(sum)
end sum_squares

start_up = proc ()
    po: stream := stream$primary_output()
    
    stream$putl(po, int$unparse(sum_squares(sequence[int]$[])))
    stream$putl(po, int$unparse(sum_squares(sequence[int]$[1,2,3,4,5])))
    stream$putl(po, int$unparse(sum_squares(sequence[int]$[42])))
end start_up
Output:
0
55
1764

CoffeeScript[edit]

sumOfSquares = ( list ) ->
    list.reduce (( sum, x ) -> sum + ( x * x )), 0

Common Lisp[edit]

(defun sum-of-squares (vector)
  (loop for x across vector sum (expt x 2)))

Cowgol[edit]

include "cowgol.coh";
include "argv.coh";

# Sum of squares
sub sumsquare(vec: [int32], len: intptr): (out: uint32) is  
    out := 0;    
    while len > 0 loop
        var cur := [vec];
        # make positive first so we can use extra range of uint32
        if cur < 0 then cur := -cur; end if;
        out := out + cur as uint32 * cur as uint32;
        vec := @next vec;
        len := len - 1;
    end loop;
end sub;


# Read array from command line, allowing empty line (giving 0)
var nums: int32[128];
var len: @indexof nums := 0;

ArgvInit();
loop
    var argmt := ArgvNext(); # read number
    if argmt == (0 as [uint8]) then
        break; # stop when no more numbers
    end if;
    
    var dummy: [uint8];
    (nums[len], dummy) := AToI(argmt);
    len := len + 1;
end loop;

# Print sum of squares of numbers
print_i32(sumsquare(&nums[0], len as intptr));
print_nl();
Output:
$ ./sumsq.386
0
$ ./sumsq.386 {1..30}
9455
$ ./sumsq.386 512
262144

Crystal[edit]

def sum_squares(a)
    a.map{|e| e*e}.sum()
end

puts sum_squares([1, 2, 3])
# => 14

D[edit]

Iterative Version[edit]

T sumSquares(T)(T[] a) pure nothrow @safe @nogc {
    T sum = 0;
    foreach (e; a)
        sum += e ^^ 2;
    return sum;
}

void main() {
    import std.stdio: writeln;

    [3.1, 1.0, 4.0, 1.0, 5.0, 9.0].sumSquares.writeln;
}
Output:
133.61

Polymorphic Functional Style[edit]

import std.stdio, std.algorithm, std.traits, std.range;

auto sumSquares(Range)(Range data) pure nothrow @safe @nogc {
    return reduce!q{a + b ^^ 2}(ForeachType!Range(0), data);
}

void main() {
    immutable items = [3.1, 1.0, 4.0, 1.0, 5.0, 9.0];
    items.sumSquares.writeln;
    10.iota.sumSquares.writeln;
}
Output:
133.61
285

Dart[edit]

Iterative Version[edit]

sumOfSquares(list) {
  var sum=0;
  list.forEach((var n) { sum+=(n*n); });
  return sum;
}
 
main() {
  print(sumOfSquares([]));
  print(sumOfSquares([1,2,3]));
  print(sumOfSquares([10]));
}
Output:
0
14
100

Functional Style Version[edit]

num sumOfSquares(List<num> l) => l.map((num x)=>x*x)
				  .fold(0, (num p,num n)=> p + n);

void main(){
  print(sumOfSquares([]));
  print(sumOfSquares([1,2,3]));
  print(sumOfSquares([10]));
}
Output:
0
14
100

Delphi[edit]

Delphi has standard SumOfSquares function in Math unit:

program SumOfSq;

{$APPTYPE CONSOLE}

uses Math;

type
  TDblArray = array of Double;

var
  A: TDblArray;

begin
  Writeln(SumOfSquares([]):6:2);            //  0.00
  Writeln(SumOfSquares([1, 2, 3, 4]):6:2);  // 30.00
  A:= nil;
  Writeln(SumOfSquares(A):6:2);             //  0.00
  A:= TDblArray.Create(1, 2, 3, 4);
  Writeln(SumOfSquares(A):6:2);             // 30.00
  Readln;
end.

Draco[edit]

proc nonrec sum_squares([*] int arr) ulong:
    ulong sum, item;
    word i, len;
    sum := 0;
    len := dim(arr,1);
    if len>0 then
        for i from 0 upto len-1 do 
            item := |arr[i];
            sum := sum + item * item
        od
    fi;
    sum
corp

proc nonrec main() void:
    type A0 = [0] int, 
         A1 = [1] int, 
         A5 = [5] int;
    
    writeln(sum_squares(A0()));
    writeln(sum_squares(A1(42)));
    writeln(sum_squares(A5(1,2,3,4,5)))
corp
Output:
0
1764
55

E[edit]

def sumOfSquares(numbers) {
    var sum := 0
    for x in numbers {
        sum += x**2
    }
    return sum
}

Eiffel[edit]

class
	APPLICATION

create
	make

feature -- Initialization

	make
		local
			a: ARRAY [INTEGER]
		do
			a := <<1, -2, 3>>
			print ("%NSquare sum of <<1, 2, 3>>: " + sum_of_square (a).out)

			a := <<>>
			print ("%NSquare sum of <<>>: " + sum_of_square (a).out)
		end

feature -- Access

	sum_of_square (a: ITERABLE [INTEGER]): NATURAL
			-- sum of square of each items
		do
			Result := 0
			across a as it loop
				Result := Result + (it.item * it.item).as_natural_32
			end
		end

end

Elena[edit]

ELENA 5.0 :

import system'routines;
import extensions;
 
SumOfSquares(list)
    = list.selectBy:(x => x * x).summarize(new Integer());
 
public program()
{
    console 
        .printLine(SumOfSquares(new int[]{4, 8, 15, 16, 23, 42}))
        .printLine(SumOfSquares(new int[]{1, 2, 3, 4, 5}))
        .printLine(SumOfSquares(Array.MinValue))
}
Output:
2854
55
0

Elixir[edit]

iex(1)> Enum.reduce([3,1,4,1,5,9], 0, fn x,sum -> sum + x*x end)
133

Emacs Lisp[edit]

(defun sum-of-squares (numbers)
  (apply #'+ (mapcar (lambda (k) (* k k)) numbers)))

(sum-of-squares (number-sequence 0 3)) ;=> 14

Erlang[edit]

lists:foldl(fun(X, Sum) -> X*X + Sum end, 0, [3,1,4,1,5,9]).

Euphoria[edit]

function SumOfSquares(sequence v)
    atom sum
    sum = 0
    for i = 1 to length(v) do
        sum += v[i]*v[i]
    end for
    return sum
end function

Excel[edit]

To find the sum of squares of values from A1 to A10, type in any other cell :

=SUMSQ(A1:A10)

The above expression will return zero if there are no values in any cell.

12	3	5	23	13	67	15	9	4	2
									
5691

F#[edit]

[1 .. 10] |> List.fold (fun a x -> a + x * x) 0 
[|1 .. 10|] |> Array.fold (fun a x -> a + x * x) 0

Factor[edit]

USE: math sequences ;

: sum-of-squares ( seq -- n ) [ sq ] map-sum ;

{ 1.0 2.0 4.0 8.0 16.0 } sum-of-squares

FALSE[edit]

0 3 1 4 1 5 9$*\ [$0=~][$*+\]#%.

Fantom[edit]

class SumSquares
{
  static Int sumSquares (Int[] numbers)
  {
    Int sum := 0
    numbers.each |n| { sum += n * n }
    return sum
  }

  public static Void main () 
  {
    Int[] n := [,]
    echo ("Sum of squares of $n = ${sumSquares(n)}")
    n = [1,2,3,4,5]
    echo ("Sum of squares of $n = ${sumSquares(n)}")
  }
}

Fish[edit]

v
\0&
>l?!v:*&+&
    >&n;

Forth[edit]

: fsum**2 ( addr n -- f )
  0e
  dup 0= if 2drop exit then
  floats bounds do
    i f@ fdup f* f+
  1 floats +loop ;

create test 3e f, 1e f, 4e f, 1e f, 5e f, 9e f,
test 6 fsum**2 f.     \ 133.

Fortran[edit]

In ISO Fortran 90 orlater, use SUM intrinsic and implicit element-wise array arithmetic:

real, dimension(1000) :: a = (/ (i, i=1, 1000) /)
real, pointer, dimension(:) :: p => a(2:1)       ! pointer to zero-length array
real :: result, zresult

result = sum(a*a)    ! Multiply array by itself to get squares

result = sum(a**2)   ! Use exponentiation operator to get squares

zresult = sum(p*p)   ! P is zero-length; P*P is valid zero-length array expression; SUM(P*P) == 0.0 as expected

FreeBASIC[edit]

' FB 1.05.0 Win64

Function SumSquares(a() As Double) As Double
  Dim As Integer length = UBound(a) - LBound(a) + 1
  If length = 0 Then Return 0.0
  Dim As Double sum = 0.0
  For i As Integer = LBound(a) To UBound(a)
    sum += a(i) * a(i)
  Next
  Return sum
End Function

Dim a(5) As Double = {1.0, 2.0, 3.0, -1.0, -2.0, -3.0}
Dim sum As Double = SumSquares(a())
Print "The sum of the squares is"; sum
Print 
Print "Press any key to quit"
Sleep
Output:
The sum of the squares is 28

Frink[edit]

f = {|x| x^2}   // Anonymous function which squares its argument
a = [1,2,3,5,7]
println[sum[map[f,a], 0]]

Fōrmulæ[edit]

Fōrmulæ programs are not textual, visualization/edition of programs is done showing/manipulating structures but not text. Moreover, there can be multiple visual representations of the same program. Even though it is possible to have textual representation —i.e. XML, JSON— they are intended for storage and transfer purposes more than visualization and edition.

Programs in Fōrmulæ are created/edited online in its website, However they run on execution servers. By default remote servers are used, but they are limited in memory and processing power, since they are intended for demonstration and casual use. A local server can be downloaded and installed, it has no limitations (it runs in your own computer). Because of that, example programs can be fully visualized and edited, but some of them will not run if they require a moderate or heavy computation/memory resources, and no local server is being used.

In this page you can see the program(s) related to this task and their results.

GAP[edit]

# Just multiplying a vector by itself yields the sum of squares (it's an inner product)
# It's necessary to check for the empty vector though
SumSq := function(v)
	if Size(v) = 0 then
		return 0;
	else
		return v*v;
	fi;
end;

GEORGE[edit]

read (n) print ;
0
1, n rep (i)
   read print dup mult +
   ]
print

data

11
 8
 12
 15
 6
 25
 19
 33
 27
 3
 37
 4

results:

 1.100000000000000E+0001  << number of values (11)
 8.000000000000000        << 11 data
 1.200000000000000E+0001
 1.500000000000000E+0001
 6.000000000000000      
 2.500000000000000E+0001
 1.900000000000000E+0001
 3.300000000000000E+0001
 2.700000000000000E+0001
 3.000000000000000      
 3.700000000000000E+0001
 4.000000000000000      
 4.667000000000000E+0003  << sum of squares

Go[edit]

Implementation
package main

import "fmt"

var v = []float32{1, 2, .5}

func main() {
    var sum float32
    for _, x := range v {
        sum += x * x
    }
    fmt.Println(sum)
}
Output:
5.25
Library
package main

import (
    "fmt"

    "github.com/gonum/floats"
)

var v = []float64{1, 2, .5}

func main() {
    fmt.Println(floats.Dot(v, v))
}
Output:
5.25

Golfscript[edit]

{0\{.*+}%}:sqsum;
# usage example
[1 2 3]sqsum puts

Groovy[edit]

def array = 1..3

// square via multiplication
def sumSq = array.collect { it * it }.sum()
println sumSq

// square via exponentiation
sumSq = array.collect { it ** 2 }.sum()

println sumSq
Output:
14
14

Haskell[edit]

Three approaches:

versions :: [[Int] -> Int]
versions =
  [ sum . fmap (^ 2)      -- ver 1
  , sum . ((^ 2) <$>)     -- ver 2
  , foldr ((+) . (^ 2)) 0 -- ver 3
  ]

main :: IO ()
main =
  mapM_ print ((`fmap` [[3, 1, 4, 1, 5, 9], [1 .. 6], [], [1]]) <$> versions)
Output:
[133,91,0,1]
[133,91,0,1]
[133,91,0,1]

Icon and Unicon[edit]

procedure main()
   local lst
   lst := []
   #Construct a simple list and pass it to getsum
   every put(lst,seq()\2)
   write(getsum(lst))
end

procedure getsum(lst)
   local total
   total := 0
   every total +:= !lst ^ 2
   return total
end

IDL[edit]

print,total(array^2)

Inform 7[edit]

Sum Of Squares is a room.

To decide which number is the sum of (N - number) and (M - number) (this is summing):
	decide on N + M.

To decide which number is (N - number) squared (this is squaring):
	decide on N * N.

To decide which number is the sum of squares of (L - list of numbers):
	decide on the summing reduction of squaring applied to L.

When play begins:
	say the sum of squares of {};
	say line break;
	say the sum of squares of {1, 2, 3};
	end the story.

Io[edit]

list(3,1,4,1,5,9) map(squared) sum

J[edit]

ss=: +/ @: *:

That is, sum composed with square. The verb also works on higher-ranked arrays. For example:

   ss 3 1 4 1 5 9
133
   ss $0           NB. $0 is a zero-length vector
0
   x=: 20 4 ?@$ 0  NB. a 20-by-4 table of random (0,1) numbers
   ss x
9.09516 5.19512 5.84173 6.6916

The computation can also be written as a loop. It is shown here for comparison only and is highly non-preferred compared to the version above.

ss1=: 3 : 0
 z=. 0
 for_i. i.#y do. z=. z+*:i{y end.
)

   ss1 3 1 4 1 5 9
133
   ss1 $0
0
   ss1 x
9.09516 5.19512 5.84173 6.6916

Java[edit]

Works with: Java version 1.5+
public class SumSquares
{
 public static void main(final String[] args)
 {
  double sum = 0;
  int[] nums = {1,2,3,4,5};
  for (int i : nums)
   sum += i * i;
  System.out.println("The sum of the squares is: " + sum);
 }
}

JavaScript[edit]

ES5[edit]

function sumsq(array) {
  var sum = 0;
  var i, iLen;

  for (i = 0, iLen = array.length; i < iLen; i++) {
    sum += array[i] * array[i];
  }
  return sum;
}

alert(sumsq([1,2,3,4,5]));  // 55

An alternative using a while loop and Math.pow

function sumsq(array) {
  var sum = 0, 
      i = array.length;

  while (i--) sum += Math.pow(array[i], 2);

  return sum;
}

alert(sumsq([1,2,3,4,5])); // 55


Library: Functional
Functional.reduce("x+y*y", 0, [1,2,3,4,5])

map (JS 1.6) and reduce (JS 1.8)

[3,1,4,1,5,9].map(function (n) { return Math.pow(n,2); }).reduce(function (sum,n) { return sum+n; });

ES6[edit]

Two ways of composing a sumOfSquares function

(() => {
    'use strict';

    // sumOfSquares :: Num a => [a] -> a
    const sumOfSquares = xs =>
        sum(xs.map(squared));

    // sumOfSquares2 :: Num a => [a] -> a
    const sumOfSquares2 = xs =>
        xs.reduce((a, x) => a + squared(x), 0);


    // ---------------------- TEST -----------------------
    const main = () => [
        sumOfSquares,
        sumOfSquares2
    ].map(
        f => f([3, 1, 4, 1, 5, 9])
    ).join('\n');


    // --------------------- GENERIC ---------------------

    // squared :: Num a => a -> a
    const squared = x =>
        Math.pow(x, 2);

    // sum :: [Num] -> Num
    const sum = xs =>
        // The numeric sum of all values in xs.
        xs.reduce((a, x) => a + x, 0);

    // MAIN ---
    return main();
})();
Output:
133
133

jq[edit]

jq supports both arrays and streams, and so we illustrate how to handle both.

# ss for an input array:
def ss: map(.*.) | add;

# ss for a stream, S, without creating an intermediate array:
def ss(S): reduce S as $x (0; . + ($x * $x) );
We can also use a generic "SIGMA" filter that behaves like the mathematical SIGMA:
# SIGMA(exp) computes the sum of exp over the input array:
def SIGMA(exp): map(exp) | add;

# SIGMA(exp; S) computes the sum of exp over elements of the stream, S,
# without creating an intermediate array:
def SIGMA(exp; S): reduce (S|exp) as $x (0; . + $x);
Finally, a "mapreduce" filter:
def mapreduce(mapper; reducer; zero): 
  if length == 0 then zero
  else map(mapper) | reducer
  end;
Demonstration:
def demo(n):
  "ss:           \( [range(0;n)] | ss )",
  "ss(S):        \( ss( range(0;n) ) )",
  "SIGMA(.*.):   \( [range(0;n)] | SIGMA(.*.) )",
  "SIGMA(.*.;S): \( SIGMA( .*.; range(0;n) ) )",
  "mapreduce(.*.; add; 0): \( [range(0;n)] | mapreduce(.*.; add; 0) )"
;

demo(3) # 0^2 + 1^2 + 2^2
Output:
"ss:           5"
"ss(S):        5"
"SIGMA(.*.):   5"
"SIGMA(.*.;S): 5"
"mapreduce(.*.; add; 0): 5"

Julia[edit]

There are several easy ways to do this in Julia:

julia> sum([1,2,3,4,5].^2)
55

julia> sum([x^2 for x in [1,2,3,4,5]])
55

julia> mapreduce(x->x^2,+,[1:5])
55

julia> sum([x^2 for x in []])
0

K[edit]

  ss: {+/x*x}
  ss 1 2 3 4 5
55
  ss@!0
0

Kotlin[edit]

Kotlin functional capabilities make this easy. map can be used to transform the elements of any array, collection, iterable or sequence, and then sum can be used to compute the sum. So .map {it * it}.sum().

However, when the input is a collection, map will also output a collection. This can be wasteful not only in terms of computation, but also in terms of memory. Piping a .asSequence() first will make the operation lazy, making it faster, and less memory intensive. A Kotlin Sequence is the spiritual equivalent of Java’s Stream

Still, Sequences are not free either. Kotlin also offers reduce and fold to do the above in a single operation. This is actually much faster than the above 2 approaches.

Finally, a classic for-loop can also be used. Note that because forEach and fold are inline functions, these are actually exactly as efficient as the had-written for-loop.

import kotlin.random.Random
import kotlin.system.measureTimeMillis
import kotlin.time.milliseconds

enum class Summer {
    MAPPING {
        override fun sum(values: DoubleArray) = values.map {it * it}.sum()
    },
    SEQUENCING {
        override fun sum(values: DoubleArray) = values.asSequence().map {it * it}.sum()
    },
    FOLDING {
        override fun sum(values: DoubleArray) = values.fold(0.0) {acc, it -> acc + it * it}
    },
    FOR_LOOP {
        override fun sum(values: DoubleArray): Double {
            var sum = 0.0
            values.forEach { sum += it * it }
            return sum
        }
    },
    ;
    abstract fun sum(values: DoubleArray): Double
}

fun main() {
    run {
        val testArrays = listOf(
            doubleArrayOf(),
            doubleArrayOf(Random.nextInt(100) / 10.0),
            DoubleArray(6) { Random.nextInt(100) / 10.0 },
        )
        for (impl in Summer.values()) {
            println("Test with ${impl.name}:")
            for (v in testArrays) println("  ${v.contentToString()} -> ${impl.sum(v)}")
        }
    }
    
    run {
        val elements = 100_000
        val longArray = DoubleArray(elements) { Random.nextDouble(10.0) }

        for (impl in Summer.values()) {
            val time = measureTimeMillis {
                impl.sum(longArray)
            }.milliseconds
            println("Summing $elements with ${impl.name} takes: $time")
        }
        var acc = 0.0
        for (v in longArray) acc += v
    }
}
Output:
Test with MAPPING:
  [] -> 0.0
  [3.5] -> 12.25
  [9.9, 9.1, 3.6, 1.2, 0.9, 2.2] -> 200.87
Test with SEQUENCING:
  [] -> 0.0
  [3.5] -> 12.25
  [9.9, 9.1, 3.6, 1.2, 0.9, 2.2] -> 200.87
Test with FOLDING:
  [] -> 0.0
  [3.5] -> 12.25
  [9.9, 9.1, 3.6, 1.2, 0.9, 2.2] -> 200.87
Test with FOR_LOOP:
  [] -> 0.0
  [3.5] -> 12.25
  [9.9, 9.1, 3.6, 1.2, 0.9, 2.2] -> 200.87
Summing 100000 elements with MAPPING takes: 31.0ms
Summing 100000 elements with SEQUENCING takes: 13.0ms
Summing 100000 elements with FOLDING takes: 2.00ms
Summing 100000 elements with FOR_LOOP takes: 2.00ms

Lambdatalk[edit]

{def sumsq
 {lambda {:s}
  {+ {S.map {lambda {:i} {* :i :i}} :s}}}}
-> sumsq

{sumsq 1 2 3 4 5}
-> 55
{sumsq 0}
-> 0

Lang5[edit]

[1 2 3 4 5] 2 ** '+ reduce .

Lasso[edit]

define sumofsquares(values::array) => {

	local(sum = 0)

	with value in #values do {
		#sum += #value * #value
	}

	return #sum
}

sumofsquares(array(1,2,3,4,5))
Output:
55

LFE[edit]

(defun sum-sq (nums)
  (lists:foldl
    (lambda (x acc)
      (+ acc (* x x)))
    0 nums))

Usage:

> (sum-sq '(3 1 4 1 5 9))
133

Liberty BASIC[edit]

'   [RC] Sum of Squares

    SourceList$     ="3 1 4 1 5 9"
    'SourceList$     =""

    '   If saved as an array we'd have to have a flag for last data.
    '   LB has the very useful word$() to read from delimited strings.
    '   The default delimiter is a space character, " ".

    SumOfSquares    =0
    n               =0
    data$           ="666"  '   temporary dummy to enter the loop.

    while data$ <>""                                '   we loop until no data left.
        data$           =word$( SourceList$, n +1)  '   first data, as a string
        NewVal          =val( data$)                '   convert string to number
        SumOfSquares    =SumOfSquares +NewVal^2     '   add to existing sum of squares
        n =n +1                                     '   increment number of data items found
    wend

    n =n -1

    print "Supplied data was ";         SourceList$
    print "This contained ";            n; " numbers."
    print "Sum of squares is ";         SumOfSquares

    end

LiveCode[edit]

put "1,2,3,4,5" into nums
repeat for each item n in nums
    add (n * n) to m
end repeat
put m  // 55

[edit]

print apply "sum map [? * ?] [1 2 3 4 5]  ; 55

Logtalk[edit]

sum(List, Sum) :-
    sum(List, 0, Sum).

sum([], Sum, Sum).
sum([X| Xs], Acc, Sum) :-
    Acc2 is Acc + X,
    sum(Xs, Acc2, Sum).

Lua[edit]

function squaresum(a, ...) return a and a^2 + squaresum(...) or 0 end
function squaresumt(t) return squaresum(unpack(t)) end

print(squaresumt{3, 5, 4, 1, 7})

M2000 Interpreter[edit]

M2000 use two concepts for arrays: standard array like A() and pointer to array as A. Pointer arithmetic not allowed here. Standard arrays are values types, and pointers are reference types. So we can handle an array both with pointer and without.

Dim A() 'make an array with zero items

A=(,) 'make a pointer to array with zero items

A=(1,) 'make a pointer to array with one item

A()=A 'make a copy of array pointed by A to A()

A=A() 'make A a pointer for A()

Dim A(10)=1 'redim A() and pass 1 to each item

k=lambda m=1->{=m:m++}  ' a lambda function with a closure m

Dim B(10)<<k()    'fill B() from 1 to 10

A()=B() ' copy B() to A(), A() object stay as is, but new items loaded, so pointer A points to A.

A+=100 ' add 100 to each element of A()

A(0)+=100 ' add 100 to first element

A()=Cons(A,A)

Now A and A() prints a 20 item array (Cons() add a list of arrays)
Print A   ' or Print A() print the same

And this is the task, using a lambda function (we can use a standard function, just use Function Square { code here })

Because M2000 modules and functions use stack for passing values, we use read statement to read a value. Functions in expressions has no return to stack because they have own stack, so passing values are filled in a fresh stack in every call. This not hold if we call function using Call (as a module), so stack is passed from parent (caller).

When we pass an array in stack, a pointer to array (to one of two interfaces) and depends the name type of a read to make this a copy or a pointer to array. So here we use: read a as a pointer to array (so it is a by reference pass). We can use Read a() and then a=a() (and remove Link a to a()), so we use by value pass, and that is a decision from callee, not the caller (this happen for objects)

Module Checkit {
      A=(1,2,3,4,5)
      Square=lambda -> {
            read a
            if len(a)=0 then =0: exit
            link a to a()
            \\ make sum same type as a(0)
            sum=a(0)-a(0)
            for i=0 to len(a)-1 {sum+=a(i)*a(i)}
            =sum
      }
      Print Square(a)=55
      Print Square((,))=0 ' empty  array
      Dim k(10)=2, L()
      Print Square(K())=40
      Print Square(L())=0
      A=(1@,2@,3@,4@,5@)
      X=Square(A)
      Print Type$(X)="Decimal", X=55@
}
Checkit

Maple[edit]

F := V -> add(v^2, v in V):
F(<1,2,3,4,5>);

Mathematica/Wolfram Language[edit]

As a function 1:

SumOfSquares[x_]:=Total[x^2]
SumOfSquares[{1,2,3,4,5}]

As a function 2:

SumOfSquares[x_]:=x.x
SumOfSquares[{1,2,3,4,5}]

Pure function 1: (postfix operator in the following examples)

{1,2,3,4,5} // Total[#^2] &

Pure function 2:

{1, 2, 3, 4, 5} // #^2 & // Total

Pure function 3:

{1, 2, 3, 4, 5} // #.#&

MATLAB[edit]

function [squaredSum] = sumofsquares(inputVector)
   squaredSum = sum( inputVector.^2 );

Maxima[edit]

nums : [3,1,4,1,5,9];
sum(nums[i]^2,i,1,length(nums));

or

nums : [3,1,4,1,5,9];
lsum(el^2, el, nums);

Mercury[edit]

:- module sum_of_squares.
:- interface.

:- import_module io.
:- pred main(io::di, io::uo) is det.

:- implementation.
:- import_module int, list.

main(!IO) :-
    io.write_int(sum_of_squares([3, 1, 4, 1, 5, 9]), !IO),
    io.nl(!IO).

:- func sum_of_squares(list(int)) = int.

sum_of_squares(Ns) = list.foldl((func(N, Acc) = Acc + N * N), Ns, 0).

min[edit]

Works with: min version 0.19.3
((bool) ((dup *) (+) map-reduce) (pop 0) if) :sq-sum

(1 2 3 4 5) sq-sum puts
() sq-sum puts
Output:
55
0

MiniScript[edit]

sumOfSquares = function(seq)
    sum = 0
    for item in seq
        sum = sum + item*item
    end for
    return sum
end function

print sumOfSquares([4, 8, 15, 16, 23, 42])
print sumOfSquares([1, 2, 3, 4, 5])
print sumOfSquares([])
Output:
2854
55
0

МК-61/52[edit]

x^2	+	С/П	БП	00

Modula-3[edit]

MODULE SumSquares EXPORTS Main;

IMPORT IO, Fmt;

TYPE RealArray = ARRAY OF REAL;

PROCEDURE SumOfSquares(x: RealArray): REAL =
  VAR sum := 0.0;
  BEGIN
    FOR i := FIRST(x) TO LAST(x) DO
      sum := sum + x[i] * x[i];
    END;
    RETURN sum;
  END SumOfSquares;

BEGIN
  IO.Put(Fmt.Real(SumOfSquares(RealArray{3.0, 1.0, 4.0, 1.0, 5.0, 9.0})));
  IO.Put("\n");
END SumSquares.

MOO[edit]

@verb #100:sum_squares this none this rd
@program #100:sum_squares
sum = 0;
list = args[1];
for i in (list)
  sum = sum + (i^2);
endfor
player:tell(toliteral(list), " => ", sum);
.

{{out}}
;#100:sum_squares({3,1,4,1,5,9})
{3, 1, 4, 1, 5, 9} => 133
;#100:sum_squares({})
{} => 0

MUMPS[edit]

SUMSQUARE(X)
 ;X is assumed to be a list of numbers separated by "^"
 NEW RESULT,I
 SET RESULT=0,I=1
 FOR  QUIT:(I>$LENGTH(X,"^"))  SET RESULT=($PIECE(X,"^",I)*$PIECE(X,"^",I))+RESULT,I=I+1
 QUIT RESULT

Nanoquery[edit]

def sum_squares(vector)
        if len(vector) = 0
                return 0
        end

        sum = 0
        for n in vector
                sum += n ^ 2
        end
        return sum
end

println sum_squares({})
println sum_squares({1, 2, 3, 4, 5})
println sum_squares({10, 3456, 2, 6})
Output:
0
55
11944076

Nemerle[edit]

SS(x : list[double]) : double
{
    |[] => 0.0
    |_  => x.Map(fun (x) {x*x}).FoldLeft(0.0, _+_)
}

NetRexx[edit]

/*NetRexx *************************************************************
* program to sum the squares of a vector of fifteen numbers.
* translated from REXX
* 14.05.2013 Walter Pachl
**********************************************************************/
numeric digits 50                   /*allow 50-digit # (default is 9)*/
v='-100 9 8 7 6 0 3 4 5 2 1 .5 10 11 12' /* vector with some #s.     */
n=v.words()
x=''
sum=0                               /*initialize   SUM   to zero.    */
                                    /*if vector is empty, sum = zero.*/
loop Until x=''                     /*loop until list is exhausted   */
  Parse v x v                       /* pick next number              */
  If x>'' Then                      /* there is a number             */
    sum=sum + x**2                  /*add its square to the sum.     */
  end
say "The sum of" n "elements for the V vector is:" sum
Output:
The sum of 15 elements for the V vector is: 10650.25

NewLISP[edit]

(apply + (map (fn(x) (* x x)) '(3 1 4 1 5 9)))
-> 133
(apply + (map (fn(x) (* x x)) '()))
-> 0

Nim[edit]

import math, sequtils

proc sumSquares[T: SomeNumber](a: openArray[T]): T =
  sum(a.mapIt(it * it))

let a1 = [1, 2, 3, 4, 5]
echo a1, " → ", sumSquares(a1)

let a2: seq[float] = @[]
echo a2, " → ", sumSquares(a2)
Output:
[1, 2, 3, 4, 5] → 55
@[] → 0.0

Objeck[edit]

bundle Default {
  class Sum {
    function : native : SquaredSum(values : Float[]) ~ Float {
       sum := 0.0;
       for(i := 0 ; i < values->Size()	; i += 1;) {
         sum += (values[i] * values[i]);
       };
       
       return sum;
    }

    function : Main(args : String[]) ~ Nil {
       SquaredSum([3.0, 1.0, 4.0, 1.0, 5.0, 9.0])->PrintLine();
     }
  }
}

OCaml[edit]

List.fold_left (fun sum a -> sum + a * a) 0 ints
List.fold_left (fun sum a -> sum +. a *. a) 0. floats

Octave[edit]

a = [1:10];
sumsq = sum(a .^ 2);

Oforth[edit]

#sq [1, 1.2, 3, 4.5 ] map sum

Ol[edit]

(define (sum-of-squares l)
   (fold + 0 (map * l l)))

(print (sum-of-squares '(1 2 3 4 5 6 7 8 9 10)))
; ==> 385

Order[edit]

#include <order/interpreter.h>

ORDER_PP(8to_lit(
  8seq_fold(8plus, 0,
            8seq_map(8fn(8X, 8times(8X, 8X)), 8seq(3, 1, 4, 1, 5, 9)))
))

Oz[edit]

declare
  fun {SumOfSquares Xs}
     for X in Xs sum:S do
        {S X*X}
     end
  end
in
  {Show {SumOfSquares [3 1 4 1 5 9]}}

PARI/GP[edit]

Generic[edit]

It is possible to apply a function, in this case ^2 to each element of an iterable and sum the result:

ss(v)={
  sum(i=1,#v,v[i]^2)
};

Specific[edit]

For this particular task the product of a row matrix and its transpose is the sum of squares:

n=[2,5,23]
print(n*n~)
n=[]
print(n*n~)
Output:
558
0

Pascal[edit]

Works with: Free_Pascal
Library: Math

Example from the documenation of the run time library:

Program Example45;

{ Program to demonstrate the SumOfSquares function. }

Uses math;

Var
  I : 1..100;
  ExArray : Array[1..100] of Float;

begin
  Randomize;
  for I:=low(ExArray) to high(ExArray) do
    ExArray[i]:=(Random-Random)*100;
  Writeln('Max             : ',MaxValue(ExArray):8:4);
  Writeln('Min             : ',MinValue(ExArray):8:4);
  Writeln('Sum squares     : ',SumOfSquares(ExArray):8:4);
  Writeln('Sum squares (b) : ',SumOfSquares(@ExArray[1],100):8:4);
end.

Perl[edit]

sub sum_of_squares {
  my $sum = 0;
  $sum += $_**2 foreach @_;
  return $sum;
}

print sum_of_squares(3, 1, 4, 1, 5, 9), "\n";

or

use List::Util qw(reduce);
sub sum_of_squares {
  reduce { $a + $b **2 } 0, @_;
}

print sum_of_squares(3, 1, 4, 1, 5, 9), "\n";

Phix[edit]

function sum_of_squares(sequence s) return sum(sq_power(s,2)) end function
?apply({{},{3,1,4,1,5,9},tagset(10)},sum_of_squares)
Output:
{0,133,385}

Phixmonti[edit]

0 tolist
10 for 0 put endfor

0 swap len for
	get
	2 power rot + swap
endfor

drop print	/# 385 #/

PHP[edit]

function sum_squares(array $args) {
    return array_reduce(
        $args, create_function('$x, $y', 'return $x+$y*$y;'), 0
    );
}

In PHP5.3 support for anonymous functions was reworked. While the above code would still work, it is suggested to use

function sum_squares(array $args) {
    return array_reduce($args, function($x, $y) { 
        return $x+$y*$y;
    }, 0);
}

Usage for both examples: sum_squares(array(1,2,3,4,5)); // 55

Picat[edit]

go =>
  List = 1..666,
  println(sum_squares(List)),
  println(sum_squares([])),
  nl.

sum_squares([]) = 0.
sum_squares(List) = sum([I*I : I in List]).
Output:
98691321
0

PicoLisp[edit]

: (sum '((N) (* N N)) (3 1 4 1 5 9))
-> 133
: (sum '((N) (* N N)) ())
-> 0

PL/I[edit]

declare A(10) float initial (10, 9, 8, 7, 6, 5, 4, 3, 2, 1);

put (sum(A**2));

Plain English[edit]

To run:
Start up.
Create a list.
Sum the squares of the list giving a ratio.
Destroy the list.
Write "Sum of squares: " then the ratio on the console.
Wait for the escape key.
Shut down.

An element is a thing with a ratio.

A list is some elements.

To add a ratio to a list:
Allocate memory for an element.
Put the ratio into the element's ratio.
Append the element to the list.

To create a list:
Add 3-1/10 to the list.
Add 1/1 to the list.
Add 4/1 to the list.
Add 1/1 to the list.
Add 5/1 to the list.
Add 9/1 to the list.

To sum the squares of a list giving a ratio:
Put 0 into the ratio.
Get an element from the list.
Loop.
If the element is nil, exit.
Add the element's ratio times the element's ratio to the ratio.
Put the element's next into the element.
Repeat.
Output:
Sum of squares: 133-61/100

Pop11[edit]

define sum_squares(v);
    lvars s = 0, j;
    for j from 1 to length(v) do
        s + v(j)*v(j) -> s;
    endfor;
    s;
enddefine;

sum_squares({1 2 3 4 5}) =>

PostScript[edit]

/sqrsum{
/x exch def
/sum 0 def
/i 0 def
x length 0 eq
{}
{
x length{
/sum sum x i get 2 exp add def
/i i 1 add def
}repeat
}ifelse
sum ==
}def
Library: initlib
[3 1 4 1 5 9] 0 {dup * +} fold

PowerShell[edit]

function Get-SquareSum ($a) {
    if ($a.Length -eq 0) {
        return 0
    } else {
        $x = $a `
             | ForEach-Object { $_ * $_ } `
             | Measure-Object -Sum
        return $x.Sum
    }
}

Prolog[edit]

   sum([],0).
   sum([H|T],S) :- sum(T, S1), S is S1 + (H * H).

PureBasic[edit]

Procedure SumOfSquares(List base())
  ForEach base()
    Sum + base()*base()
  Next
  ProcedureReturn Sum
EndProcedure

Python[edit]

Using generator expression

sum(x * x for x in [1, 2, 3, 4, 5])
# or
sum(x ** 2 for x in [1, 2, 3, 4, 5])
# or
sum(pow(x, 2) for x in [1, 2, 3, 4, 5])

Functional versions:

# using lambda and map:
sum(map(lambda x: x * x, [1, 2, 3, 4, 5]))
# or 
sum(map(lambda x: x ** 2, [1, 2, 3, 4, 5]))
# or 
sum(map(lambda x: pow(x, 2), [1, 2, 3, 4, 5]))

# using pow and repeat
from itertools import repeat
sum(map(pow, [1, 2, 3, 4, 5], repeat(2)))

# using starmap and mul
from itertools import starmap
from operator import mul
a = [1, 2, 3, 4, 5]
sum(starmap(mul, zip(a, a)))

# using reduce
from functools import reduce
powers_of_two = (x * x for x in [1, 2, 3, 4, 5])
reduce(lambda x, y : x + y, powers_of_two)
# or
from operator import add
powers_of_two = (x * x for x in [1, 2, 3, 4, 5])
reduce(add, powers_of_two)
# or using a bit more complex lambda
reduce(lambda a, x: a + x*x, [1, 2, 3, 4, 5])

Using NumPy:

import numpy as np
a = np.array([1, 2, 3, 4, 5])
np.sum(a ** 2)

Q[edit]

ssq:{sum x*x}

Quackery[edit]

  [ 0 swap witheach [ 2 ** + ] ] is sumofsquares ( [ --> n )
Output:

Testing in the Quackery shell.

> quackery

Welcome to Quackery.

Enter "leave" to leave the shell.

/O> [ 0 swap witheach [ 2 ** + ] ] is sumofsquares
... ' [ 2 3 5 7 11 13 17 ] sumofsquares echo cr
... ' [ ] sumofsquares echo cr
... leave
... 
666
0

Sayonara.

R[edit]

arr <- c(1,2,3,4,5)
result <- sum(arr^2)

Racket[edit]

#lang racket
(for/sum ([x #(3 1 4 1 5 9)]) (* x x))

Raku[edit]

(formerly Perl 6)

say [+] map * ** 2, (3, 1, 4, 1, 5, 9);

If this expression seems puzzling, note that * ** 2 is equivalent to {$^x ** 2}— the leftmost asterisk is not the multiplication operator but the Whatever star, which specifies currying behavior. Another convenient way to distribute the exponentiation is via the cross metaoperator, which as a list infix is looser than comma in precedence but tighter than the reduction list operator:

say [+] <3 1 4 1 5 9> X** 2

Raven[edit]

define sumOfSqrs use $lst
   0 $lst each dup * +

[ 1 2 3 4] sumOfSqrs "Sum of squares: %d\n" print
Output:
Sum of squares: 30

Red[edit]

Red [
    date: 2021-10-25
    red-version: 0.6.4
    description: "Find the sum of squares of a numeric vector"
]

sum-squares: function [
    "Returns the sum of squares of all values in a block"
    values [any-list! vector!]
][
    result: 0
    foreach value values [result: value * value + result]
    result
]

print sum-squares []
print sum-squares [1 2 0.5]
Output:
0
5.25

ReScript[edit]

With integers:

let sumOfSquares = (acc, item) => { acc + item * item }

Js.log(Js.Array2.reduce([10, 2, 4], sumOfSquares, 0))

With floats:

let sumOfSquares = (acc, item) => { acc +. item *. item }

Js.log(Js.Array2.reduce([10., 2., 4.], sumOfSquares, 0.))

REXX[edit]

input from pgm[edit]

/*REXX program  sums  the squares of the numbers  in a (numeric)  vector of 15 numbers. */
numeric digits 100                               /*allow 100─digit numbers; default is 9*/
v= -100 9 8 7 6 0 3 4 5 2 1 .5 10 11 12          /*define a vector with fifteen numbers.*/
#=words(v)                                       /*obtain number of words in the V list.*/
$= 0                                             /*initialize the  sum  ($)  to zero.   */
       do k=1  for #                             /*process each number in the V vector. */
       $=$ + word(v,k)**2                        /*add a squared element to the ($) sum.*/
       end   /*k*/                               /* [↑]  if vector is empty, then sum=0.*/
                                                 /*stick a fork in it,  we're all done. */
say 'The sum of '      #      " squared elements for the  V  vector is: "   $

output   using an internal vector (list) of numbers:

The sum of  15  squared elements for the  V  vector is:  10650.25

input from C.L.[edit]

/*REXX program  sums  the squares of the numbers  in a (numeric)  vector of 15 numbers. */
numeric digits 100                               /*allow 100─digit numbers; default is 9*/
parse arg v                                      /*get optional numbers from the C.L.   */
if v=''  then v= -100 9 8 7 6 0 3 4 5 2 1 .5 10 11 12      /*Not specified?  Use default*/
#=words(v)                                                 /*obtain number of words in V*/
say 'The vector of '    #     " elements is: "   space(v)  /*display the vector numbers.*/
$= 0                                             /*initialize the  sum  ($)  to zero.   */
             do  until v=='';   parse var v x v  /*process each number in the V vector. */
             $=$ + x**2                          /*add a squared element to the ($) sum.*/
             end   /*until*/                     /* [↑]  if vector is empty, then sum=0.*/
say                                              /*stick a fork in it,  we're all done. */
say 'The sum of '       #     " squared elements for the  V  vector is: "      $

output   using a vector (list) of numbers from the command line:

The vector of  10  elements is:  -1000 -100 -10 -1 0 +1 +10 100 1000 1e20

The sum of  10  squared elements for the  V  vector is:  10000000000000000000000000000000002020202

Ring[edit]

aList = [1,2,3,4,5]
see sumOfSquares(aList)

func sumOfSquares sos
sumOfSquares = 0
for i=1 to len(sos)
    sumOfSquares = sumOfSquares + pow(sos[i],2)
next
return sumOfSquares

Ruby[edit]

[3,1,4,1,5,9].sum(0){|x| x*x}

Run BASIC[edit]

list$ = "1,2,3,4,5"
print sumOfSquares(list$)

FUNCTION sumOfSquares(sos$)
  while word$(sos$,i+1,",") <> ""
    i = i + 1
    sumOfSquares = sumOfSquares + val(word$(sos$,i,","))^2
  wend
END FUNCTION

Rust[edit]

fn sq_sum(v: &[f64]) -> f64 {
    v.iter().fold(0., |sum, &num| sum + num*num)
}

fn main() {
    let v = vec![3.0, 1.0, 4.0, 1.0, 5.5, 9.7];
    println!("{}", sq_sum(&v));

    let u : Vec<f64> = vec![];
    println!("{}", sq_sum(&u));
}

Sather[edit]

class MAIN is

  sqsum(s, e:FLT):FLT is
    return s + e*e;
  end;

  sum_of_squares(v :ARRAY{FLT}):FLT is
    return (#ARRAY{FLT}(|0.0|).append(v)).reduce(bind(sqsum(_,_)));
  end;

  main is
    v :ARRAY{FLT} := |3.0, 1.0, 4.0, 1.0, 5.0, 9.0|;
    #OUT + sum_of_squares(v) + "\n";
  end;

end;

Scala[edit]

Unfortunately there is no common "Numeric" class that Int and Double both extend, since Scala's number representation maps closely to Java's. Those concerned about precision can define a similar procedure for integers.

def sum_of_squares(xs: Seq[Double]) = xs.foldLeft(0) {(a,x) => a + x*x}

Scheme[edit]

(define (sum-of-squares l)
  (apply + (map * l l)))
> (sum-of-squares (list 3 1 4 1 5 9))
133

Seed7[edit]

$ include "seed7_05.s7i";
  include "float.s7i";
 
const array float: list1 is [] (3.0, 1.0, 4.0, 1.0, 5.0, 9.0);
const array float: list2 is 0 times 0.0;

const func float: squaredSum (in array float: floatList) is func
  result
    var float: sum is 0.0;
  local
    var float: number is 0.0;
  begin
    for number range floatList do
      sum +:= number ** 2;
    end for;
  end func;
 
const proc: main is func
  begin
    writeln(squaredSum(list1));
    writeln(squaredSum(list2));
  end func;

Sidef[edit]

func sum_of_squares(vector) {
    var sum = 0;
    vector.each { |n| sum += n**2 };
    return sum;
}

say sum_of_squares([]);         # 0
say sum_of_squares([1,2,3]);    # 14

Slate[edit]

{1. 2. 3} reduce: [|:x :y| y squared + x].
{} reduce: [|:x :y| y squared + x] ifEmpty: [0].

Smalltalk[edit]

#(3 1 4 1 5 9) inject: 0 into: [:sum :aNumber | sum + aNumber squared]

SNOBOL4[edit]

Works with: Macro Spitbol
Works with: Snobol4+
Works with: CSnobol
        define('ssq(a)i') :(ssq_end)
ssq     i = i + 1; ssq = ssq + (a<i> * a<i>) :s(sumsq)f(return)
ssq_end

*       # Fill array, test and display
        str = '1 2 3 5 7 11 13 17 19 23'; a = array(10)
loop    i = i + 1; str len(p) span('0123456789') . a<i> @p :s(loop)
        output = str ' -> ' sumsq(a)
end
Output:
 1 2 3 5 7 11 13 17 19 23 -> 1557

SQL[edit]

select sum(x*x) from vector

Note that this assumes that the values in our vector are named x.

Standard ML[edit]

foldl (fn (a, sum) => sum + a * a) 0 ints
foldl (fn (a, sum) => sum + a * a) 0.0 reals

Stata[edit]

Mata[edit]

a = 1..100
sum(a:^2)
  338350

a = J(0, 1, .)
length(a)
  0
sum(a:^2)
  0

Swift[edit]

func sumSq(s: [Int]) -> Int {
  return s.map{$0 * $0}.reduce(0, +)
}

Tailspin[edit]

templates ssq
  when <[](0)> do 0 !
  otherwise $... -> $*$ -> ..=Sum&{of: :()} !
end ssq

[] -> ssq -> !OUT::write // outputs 0
[1..5] -> ssq -> !OUT::write // outputs 55

Tcl[edit]

package require Tcl 8.6
namespace path ::tcl::mathop

# {*} is like apply in Scheme--it turns a list into multiple arguments
proc sum_of_squares lst {
    + {*}[lmap x $lst {* $x $x}]
}
puts [sum_of_squares {1 2 3 4}]; # ==> 30
puts [sum_of_squares {}];        # ==> 0

Trith[edit]

[3 1 4 1 5 9] 0 [dup * +] foldl

TUSCRIPT[edit]

$$ MODE TUSCRIPT
array="3'1'4'1'5'9",sum=0
LOOP a=array
sum=sum+(a*a)
ENDLOOP
PRINT sum
Output:
133 

UnixPipes[edit]

folder() {
   (read B; res=$( expr $1 \* $1 ) ; test -n "$B" && expr $res + $B || echo $res)
}

fold() {
   (while read a ; do
       fold | folder $a
   done)
}


(echo 3; echo 1; echo 4;echo 1;echo 5; echo 9) | fold

Unix shell[edit]

$ cat toto
1
2
4
8
16
$ cat toto toto | paste -sd*
1*2*4*8*16*1*2*4*8*16
$ cat toto toto | paste -sd* | bc -l
1048576

Ursala[edit]

The ssq function defined below zips two copies of its argument together, maps the product function to all pairs, and then sums the result by way of the reduction operator, -:.

#import nat

ssq = sum:-0+ product*iip

#cast %n

main = ssq <21,12,77,0,94,23,96,93,72,72,79,24,8,50,9,93>
Output:
62223

V[edit]

[sumsq [dup *] map 0 [+] fold].

[] sumsq
=0
[1 2 3] sumsq
=14

VBA[edit]

Public Sub sum_of_squares()
    Debug.Print WorksheetFunction.SumSq([{1,2,3,4,5,6,7,8,9,10}])
End Sub
Output:
 385 

VBScript[edit]

Function sum_of_squares(arr)
	If UBound(arr) = -1 Then
		sum_of_squares = 0
	End If
	For i = 0 To UBound(arr)
		sum_of_squares = sum_of_squares + (arr(i)^2)
	Next
End Function

WScript.StdOut.WriteLine sum_of_squares(Array(1,2,3,4,5))
WScript.StdOut.WriteLine sum_of_squares(Array())
Output:
55
0

Visual Basic .NET[edit]

 Private Shared Function sumsq(ByVal i As ICollection(Of Integer)) As Integer
        If i Is Nothing OrElse i.Count = 0 Then
            Return 0
        End If
        Return i.[Select](Function(x) x * x).Sum()
 End Function

 Private Shared Sub Main()
        Dim a As Integer() = New Integer() {1, 2, 3, 4, 5}
        ' 55
        Console.WriteLine(sumsq(a))
 
        For K As Integer = 0 To 16
               Console.WriteLine("SumOfSquares({0}) = {1}", K, SumOfSquares(K))
        Next
 End Sub
 Function SumOfSquares(ByVal Max As Integer)
        Dim Square As Integer = 0
        Dim Add As Integer = 1
        Dim Sum As Integer = 0
        For J As Integer = 0 To Max - 1
            Square += Add
            Add += 2
            Sum += Square
        Next
        Return Sum
 End Function

 Function SumOfSquaresByMult(ByVal Max As Integer)
        Dim Sum As Integer = 0
        For J As Integer = 1 To Max
            Sum += J * J
        Next
        Return Sum
 End Function
Output:
55
SumOfSquares(0) = 0
SumOfSquares(1) = 1
SumOfSquares(2) = 5
SumOfSquares(3) = 14
SumOfSquares(4) = 30
SumOfSquares(5) = 55
SumOfSquares(6) = 91
SumOfSquares(7) = 140
SumOfSquares(8) = 204
SumOfSquares(9) = 285
SumOfSquares(10) = 385
SumOfSquares(11) = 506
SumOfSquares(12) = 650
SumOfSquares(13) = 819
SumOfSquares(14) = 1015
SumOfSquares(15) = 1240
SumOfSquares(16) = 1496

Wortel[edit]

@sum !*^@sq [3 1 4 1 5 9] ; returns 133
@sum !*^@sq [] ; returns 0

As a function:

^(@sum *^@sq)

Iterative function:

&a [@var sum 0 @for x of a :!+sum *x x sum]

Wren[edit]

var sumSquares = Fn.new { |v| v.reduce(0) { |sum, n| sum + n * n } }

var v = [1, 2, 3, -1, -2, -3]
System.print("Vector         : %(v)")
System.print("Sum of squares : %(sumSquares.call(v))")
Output:
Vector         : [1, 2, 3, -1, -2, -3]
Sum of squares : 28

XLISP[edit]

The task specification calls for a function that takes a numeric vector. If you want a function that takes a linked list (which would be more idiomatic), just extract the inner function SUMSQ and use that instead of SUM-OF-SQUARES.

(defun sum-of-squares (vec)
    (defun sumsq (xs)
        (if (null xs)
            0
            (+ (expt (car xs) 2) (sumsq (cdr xs)))))
    (sumsq (vector->list vec)))

(define first-seven-primes #(2 3 5 7 11 13 17))

(define zero-length-vector #())

(print `(the sum of the squares of the first seven prime numbers is ,(sum-of-squares first-seven-primes)))

(print `(the sum of the squares of no numbers at all is ,(sum-of-squares zero-length-vector)))
Output:
(THE SUM OF THE SQUARES OF THE FIRST SEVEN PRIME NUMBERS IS 666) 
(THE SUM OF THE SQUARES OF NO NUMBERS AT ALL IS 0)

XPL0[edit]

include c:\cxpl\codes;  \intrinsic 'code' declarations

func SumSq(V, L);
int  V, L;
int  S, I;
[S:= 0;
for I:= 0 to L-1 do S:= S+sq(V(I));
return S;
]; \SumSq

[IntOut(0, SumSq([1,2,3,4,5,6,7,8,9,10], 10));  CrLf(0);
 IntOut(0, SumSq([0], 0));  CrLf(0);    \zero-length vector "[]" doesn't compile
]
Output:
385
0

zkl[edit]

T().reduce(fcn(p,n){ p + n*n },0)               //-->0
T(3,1,4,1,5,9).reduce(fcn(p,n){ p + n*n },0.0) //-->133.0
[1..5].reduce(fcn(p,n){ p + n*n },0)          //-->55