Sum of squares

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

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).

See also Mean.

Contents

[edit] ACL2

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

[edit] ActionScript

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;
}

[edit] Ada

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;

Sample output:

 0.00000E+00
 1.33000E+02

[edit] ALGOL 68

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

[edit] Alore

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

[edit] APL

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

[edit] AutoHotkey

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

[edit] AWK

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

[edit] BASIC

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

[edit] BBC BASIC

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

[edit] bc

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

[edit] Bracmat

( ( 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

[edit] Brat

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

[edit] C

#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;
}

[edit] C++

#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;
}
Alternative version using
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);
}

[edit] C#

using System;
using System.Collections.Generic;
using System.Linq;
 
class Program {
static int sumsq(ICollection<int> i) {
if (i == null || i.Count == 0) return 0;
return i.Select(x => x * x).Sum();
}
 
static void Main() {
int[] a = { 1, 2, 3, 4, 5 };
Console.WriteLine(sumsq(a)); // 55
}
}

[edit] Chef

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.
 
 

[edit] Clojure

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

[edit] CoffeeScript

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

[edit] Common Lisp

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

[edit] D

[edit] Iterative Version

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

[edit] Polymorphic Functional Style

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

[edit] Dart

[edit] Iterative Version

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

[edit] Functional Style Version

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

[edit] Delphi

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.

[edit] E

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


[edit] Eiffel

 
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
 

[edit] Erlang

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

[edit] Euphoria

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

[edit] Excel

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
 

[edit] Factor

USE: math sequences ;
 
: sum-of-squares ( seq -- n ) [ sq ] map-sum ;
 
{ 1.0 2.0 4.0 8.0 16.0 } sum-of-squares

[edit] FALSE

 
0 3 1 4 1 5 9$*\ [$0=~][$*+\]#%.
 

[edit] Fantom

 
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)}")
}
}
 

[edit] Fish

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

[edit] Forth

: 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.

[edit] Fortran

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

[edit] Frink

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

[edit] F#

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

[edit] GAP

# 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;

[edit] GEORGE

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

[edit] Go

package main
 
import "fmt"
 
func main() {
var sum float32
for _, x := range []float32{1,2,.5} {
sum += x*x
}
fmt.Println(sum)
}

[edit] Golfscript

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

[edit] Groovy

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

[edit] Haskell

sumOfSquares = sum . map (^ 2)
 
> sumOfSquares [3,1,4,1,5,9]
133

[edit] IDL

print,total(array^2)

[edit] Icon and Unicon

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

[edit] Inform 7

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.

[edit] Io

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

[edit] J

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

[edit] Java

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);
}
}

[edit] JavaScript

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; });

[edit] K

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

[edit] Julia

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

[edit] Lang5

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


[edit] Lasso

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

[edit] Liberty BASIC

'   [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

[edit]

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

[edit] Logtalk

sum(List, Sum) :-
sum(List, 0, Sum).
 
sum([], Sum, Sum).
sum([X| Xs], Acc, Sum) :-
Acc2 is Acc + X,
sum(Xs, Acc2, Sum).

[edit] Lua

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})

[edit] Maple

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

[edit] Mathematica

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} // #.#&

[edit] MATLAB

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

[edit] Maxima

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);

[edit] Mercury

 
:- 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).
 

[edit] МК-61/52

x^2	+	С/П	БП	00

[edit] Modula-3

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.

[edit] MOO

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

[edit] MUMPS

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

[edit] Nemerle

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

[edit] NetRexx

/*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

[edit] NewLISP

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

[edit] Nimrod

import math, sequtils
 
echo sum(map(@[1,2,3,4,5], proc (x: int): int = x*x))

[edit] Objeck

 
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();
}
}
}
 

[edit] OCaml

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

[edit] Octave

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

[edit] Order

#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)))
))

[edit] Oz

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]}}

[edit] PARI/GP

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

[edit] Pascal

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.

[edit] Perl

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";

[edit] Perl 6

Works with: Rakudo version #21 "Seattle"
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

[edit] PHP

 
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

[edit] PicoLisp

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

[edit] PL/I

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

[edit] Pop11

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}) =>

[edit] PostScript

 
/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
 

[edit] PowerShell

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

[edit] PureBasic

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

[edit] Python

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

Functional version:

sum(map(lambda x: x*x, [1, 2, 3, 4, 5]))

[edit] Prolog

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

[edit] R

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

[edit] Racket

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

[edit] Raven

define sumOfSqrs use $lst
0 $lst each dup * +
 
[ 1 2 3 4] sumOfSqrs "Sum of squares: %d\n" print
Output:
Sum of squares: 30

[edit] REXX

/*REXX program  sums  the squares of a vector which contains 15 numbers.*/
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 /*define a vector with some #s. */
sum=0 /*initialize SUM to zero. */
/*if vector is empty, sum = zero.*/
do k=1 for words(v) /*process each number in the list*/
sum=sum + word(v,k)**2 /*add squared element to the sum.*/
end /*k*/
 
say 'The sum of ' words(v) " squared elements for the V vector is: " sum
/*stick a fork in it, we're done.*/
/*stick a fork in it, we're done.*/

output

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

[edit] Ruby

[3,1,4,1,5,9].inject(0) { |sum,x| sum += x**2 }

or

[3,1,4,1,5,9].map { |x| x**2 }.reduce(0, :+)

[edit] Run BASIC

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

[edit] Rust

fn sqsum(v: Vec<f64>) -> f64 {
let mut s = 0.0;
 
for i in v.iter() {
s += *i * *i;
}
 
return s;
}
 
fn main() {
let v = vec!(3.0, 1.0, 4.0, 1.0, 5.0, 9.0);
println!("{}", sqsum(v));
 
let u : Vec<f64> = vec!();
println!("{}", sqsum(u));
}

[edit] Sather

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;

[edit] Scala

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}

[edit] Scheme

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

[edit] Seed7

$ 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;

[edit] Slate

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

[edit] Smalltalk

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

[edit] SNOBOL4

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

[edit] Standard ML

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

[edit] SQL

SELECT SUM(x*x) FROM vector

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

[edit] Tcl

proc sumOfSquares {nums} {
set sum 0
foreach num $nums {
set sum [expr {$sum + $num**2}]
}
return $sum
}
sumOfSquares {1 2 3 4 5} ;# ==> 55
sumOfSquares {} ;# ==> 0
Library: Tcllib (Package: struct::list)
package require struct::list
 
proc square x {expr {$x * $x}}
proc + {a b} {expr {$a + $b}}
proc sumOfSquares {nums} {
struct::list fold [struct::list map $nums square] 0 +
}
sumOfSquares {1 2 3 4 5} ;# ==> 55
sumOfSquares {} ;# ==> 0

Generic "sum of function"

package require Tcl 8.5
package require struct::list
namespace path ::tcl::mathop
 
proc sum_of {lambda nums} {
struct::list fold [struct::list map $nums [list apply $lambda]] 0 +
}
 
sum_of {x {* $x $x}} {1 2 3 4 5} ;# ==> 55

[edit] Trith

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

[edit] TUSCRIPT

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

Output:

133 

[edit] UnixPipes

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

[edit] Ursala

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

[edit] V

[sumsq [dup *] map 0 [+] fold].
 
[] sumsq
=0
[1 2 3] sumsq
=14

[edit] Visual Basic .NET

 
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

[edit] Wortel

@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]

[edit] XPL0

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

[edit] zkl

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