Sum of squares: Difference between revisions
(Undo revision 111928 by 79.169.56.225 (talk) don't force your style on others) |
|||
Line 120: | Line 120: | ||
=={{header|C}}== |
=={{header|C}}== |
||
<lang c>#include < |
<lang c>#include <stdio.h> |
||
#include <stdio.h> |
|||
⚫ | |||
⚫ | |||
{ |
{ |
||
int i; |
int i; double sum = 0.0; |
||
for(i = 0 ; i < e ; i++) sum += l[i]*l[i]; |
|||
for (i = 0; i < e; i++) |
|||
sum += (l[i] * l[i]); |
|||
return sum; |
return sum; |
||
} |
} |
||
int main( |
int main() |
||
{ |
{ |
||
double list[6] = {3.0, 1.0, 4.0, 1.0, 5.0, 9.0}; |
double list[6] = {3.0, 1.0, 4.0, 1.0, 5.0, 9.0}; |
||
char format[] = "%lf\n"; |
|||
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 */ |
/* the same without using a real list as if it were 0-element long */ |
||
printf("%lf\n", squaredsum(NULL, 0)); |
|||
return |
return 0; |
||
}</lang> |
}</lang> |
||
Revision as of 04:06, 28 June 2011
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.
ActionScript
<lang 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; }</lang>
Ada
<lang 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;</lang> Sample output:
0.00000E+00 1.33000E+02
ALGOL 68
The computation can be written as a loop. <lang algol68>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))));
)</lang> Output:
133
Another implementation could define a procedure (proc) or operator (op) called map.
<lang algol68>[]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 ))
)</lang> Output:
133 133
AutoHotkey
<lang autohotkey>list = 3 1 4 1 5 9 Loop, Parse, list, %A_Space%
sum += A_LoopField**2
MsgBox,% sum</lang>
AWK
Vectors are read, space-separated, from stdin; sum of squares goes to stdout. The empty line produces 0. <lang awk>$ awk '{s=0;for(i=1;i<=NF;i++)s+=$i*$i;print s}' 3 1 4 1 5 9 133
0</lang>
BASIC
Assume the numbers are in an array called a
.
<lang qbasic>sum = 0
FOR I = LBOUND(a) TO UBOUND(a)
sum = sum + a(I) ^ 2
NEXT I PRINT "The sum of squares is: " + sum</lang>
BBC BASIC
BBC BASIC cannot have a zero-length array. <lang bbcbasic> DIM vector(5)
vector() = 1, 2, 3, 4, 5, 6 PRINT "Sum of squares = " ; MOD(vector()) ^ 2</lang>
Output:
Sum of squares = 91
Brat
<lang brat>p 1.to(10).reduce 0 { res, n | res = res + n ^ 2 } #Prints 385</lang>
C
<lang 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;
}</lang>
C++
<lang cpp>#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;
}</lang>
Alternative version using
:
<lang cpp>#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);
}</lang>
C#
<lang csharp>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 }
}</lang>
Chef
<lang 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.
</lang>
Clojure
<lang clojure>(defn sum-of-squares [v]
(reduce #(+ %1 (* %2 %2)) 0 v))</lang>
Common Lisp
<lang lisp>(defun sum-of-squares (vector)
(loop for x across vector sum (expt x 2)))</lang>
D
<lang d>import std.stdio: writeln;
T sumSquares(T)(T[] a) {
T sum = 0; foreach (e; a) sum += e ^^ 2; return sum;
}
void main() {
auto array = [3.1, 1.0, 4.0, 1.0, 5.0, 9.0]; writeln(sumSquares(array));
}</lang> Output:
133.61
Polymorphic functional style, same output: <lang d>import std.stdio, std.algorithm, std.traits;
auto sumSquares(Range)(const Range data) {
return reduce!q{a + b ^^ 2}(cast(ForeachType!Range)0, data);
}
void main() {
auto array = [3.1, 1.0, 4.0, 1.0, 5.0, 9.0]; writeln(sumSquares(array));
}</lang>
Delphi
Delphi has standard SumOfSquares function in Math unit: <lang Delphi>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.</lang>
E
<lang e>def sumOfSquares(numbers) {
var sum := 0 for x in numbers { sum += x**2 } return sum
}</lang>
Erlang
<lang erlang>lists:foldl(fun(X, Sum) -> X*X + Sum end, 0, [3,1,4,1,5,9]).</lang>
Euphoria
<lang 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</lang>
Factor
<lang 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</lang>
Fantom
<lang 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)}") }
} </lang>
Forth
<lang 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.</lang>
Fortran
In ISO Fortran 90 orlater, use SUM intrinsic and implicit element-wise array arithmetic: <lang fortran>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</lang>
F#
<lang fsharp>[1 .. 10] |> List.fold (fun a x -> a + x * x) 0 [|1 .. 10|] |> Array.fold (fun a x -> a + x * x) 0</lang>
GAP
<lang 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;</lang>
Go
<lang go>package main
import "fmt"
func main() {
var sum float32 for _, x := range []float32{1,2,.5} { sum += x*x } fmt.Println(sum)
}</lang>
Golfscript
<lang golfscript>{0\{.*+}%}:sqsum;
- usage example
[1 2 3]sqsum puts</lang>
Groovy
<lang 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</lang>
Output:
14 14
Haskell
<lang haskell>sumOfSquares = sum . map (^ 2)
> sumOfSquares [3,1,4,1,5,9] 133</lang>
IDL
<lang idl>print,total(array^2)</lang>
Icon and Unicon
<lang icon>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</lang>
Inform 7
<lang inform7>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.</lang>
Io
<lang io>list(3,1,4,1,5,9) map(squared) sum</lang>
J
<lang j>ss=: +/ @: *:</lang>
That is, sum composed with square. The verb also works on higher-ranked arrays. For example:
<lang j> 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</lang>
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.
<lang j>ss1=: 3 : 0
z=. 0 for_i. i.#y do. z=. z+*:i{y end.
)
ss1 3 1 4 1 5 9
133
ss1 $0
0
ss1 x
9.09516 5.19512 5.84173 6.6916</lang>
Java
Assume the numbers are in a double array called "nums". <lang java5>public class SumSquares {
public static void main(final String[] args) { double sum = 0; int[] nums = {1,2,3,4,5}; for (int i : sum) sum += i * i; System.out.println("The sum of the squares is: " + sum); }
}</lang>
JavaScript
<lang javascript>function sumsq(array) {
var sum = 0, i; for (i = 0; i < array.length; i++) { sum += array[i] * array[i]; } return sum;
}
alert(sumsq([1,2,3,4,5]));</lang>
<lang javascript>Functional.reduce("x+y*y", 0, [1,2,3,4,5])</lang>
map (JS 1.6) and reduce (JS 1.8)
<lang javascript>[3,1,4,1,5,9].map(function (n) { return Math.pow(n,2); }).reduce(function (sum,n) { return sum+n; });</lang>
K
<lang k>
ss: {+/x*x} ss 1 2 3 4 5
55
ss@!0
0 </lang>
Liberty BASIC
<lang lb>' [RC] Sum of Squares
SourceList$ ="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</lang>
Logo
<lang logo>print apply "sum map [? * ?] [1 2 3 4 5] ; 55</lang>
Logtalk
<lang logtalk>sum(List, Sum) :-
sum(List, 0, Sum).
sum([], Sum, Sum). sum([X| Xs], Acc, Sum) :-
Acc2 is Acc + X, sum(Xs, Acc2, Sum).</lang>
Lua
<lang 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})</lang>
Mathematica
As a function 1: <lang mathematica>SumOfSquares[x_]:=Total[x^2] SumOfSquares[{1,2,3,4,5}]</lang> As a function 2: <lang mathematica>SumOfSquares[x_]:=x.x SumOfSquares[{1,2,3,4,5}]</lang> Pure function 1: (postfix operator in the following examples) <lang mathematica>{1,2,3,4,5} // Total[#^2] &</lang> Pure function 2: <lang mathematica>{1, 2, 3, 4, 5} // #^2 & // Total</lang> Pure function 3: <lang mathematica>{1, 2, 3, 4, 5} // #.#&</lang>
MATLAB
<lang Matlab>function [squaredSum] = sumofsquares(inputVector)
squaredSum = sum( inputVector.^2 );</lang>
Maxima
<lang maxima>nums : [3,1,4,1,5,9]; sum(nums[i]^2,i,1,length(nums));</lang>
Modula-3
<lang modula3>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.</lang>
Objeck
<lang 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(); } }
} </lang>
OCaml
<lang ocaml>List.fold_left (fun sum a -> sum + a * a) 0 ints</lang>
<lang ocaml>List.fold_left (fun sum a -> sum +. a *. a) 0. floats</lang>
Octave
<lang octave>a = [1:10]; sumsq = sum(a .^ 2);</lang>
Oz
<lang 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]}}</lang>
PARI/GP
<lang>ss(v)={
sum(i=1,#v,v[i]^2)
};</lang>
Perl
<lang perl>sub sum_of_squares {
my $sum = 0; $sum += $_**2 foreach @_; return $sum;
}
print sum_of_squares(3, 1, 4, 1, 5, 9), "\n";</lang> or <lang perl>use List::Util qw(reduce); sub sum_of_squares {
reduce { $a + $b **2 } 0, @_;
}
print sum_of_squares(3, 1, 4, 1, 5, 9), "\n";</lang>
Perl 6
<lang perl6>say [+] map * ** 2, 3, 1, 4, 1, 5, 9;</lang>
If this expression seems puzzling, note that * ** 2
is equivalent to {$^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:
<lang perl6>say [+] 3,1,4,1,5,9 X** 2</lang>
PHP
<lang php> function sum_squares(array $args) {
return array_reduce( $args, create_function('$x, $y', 'return $x+$y*$y;'), 0 );
} </lang>
In PHP5.3 support for anonymous functions was reworked. While the above code would still work, it is suggested to use
<lang php> function sum_squares(array $args) {
return array_reduce($args, function($x, $y) { return $x+$y*$y; }, 0);
}
</lang>
Usage for both examples: sum_squares(array(1,2,3,4,5)); // 55
PicoLisp
<lang PicoLisp>: (sum '((N) (* N N)) (3 1 4 1 5 9)) -> 133
- (sum '((N) (* N N)) ())
-> 0</lang>
PL/I
<lang PL/I> declare A(10) float initial (10, 9, 8, 7, 6, 5, 4, 3, 2, 1);
put (sum(A**2)); </lang>
Pop11
<lang pop11>define sum_squares(v);
lvars s = 0, j; for j from 1 to length(v) do s + v(j)*v(j) -> s; endfor; s;
enddefine;
sum_squares({1 2 3 4 5}) =></lang>
PostScript
<lang> /sqrsum{ /x exch def /sum 0 def /i 0 def x length 0 eq {} { x length{ /sum sum x i get 2 exp add def /i i 1 add def }repeat }ifelse sum == }def </lang>
<lang postscript> [3 1 4 1 5 9] 0 {dup * +} fold </lang>
PowerShell
<lang powershell>function Get-SquareSum ($a) {
if ($a.Length -eq 0) { return 0 } else { $x = $a ` | ForEach-Object { $_ * $_ } ` | Measure-Object -Sum return $x.Sum }
}</lang>
PureBasic
<lang PureBasic>Procedure SumOfSquares(List base())
ForEach base() Sum + base()*base() Next ProcedureReturn Sum
EndProcedure</lang>
Python
<lang python>sum(x*x for x in [1, 2, 3, 4, 5])</lang>
Prolog
sum([],0). sum([H|T],S) :- sum(T, S1), S is S1 + (H * H).
R
<lang r>arr <- c(1,2,3,4,5) result <- sum(arr^2)</lang>
REXX
<lang rexx> /*REXX program to sum the squares of a vector. */
numeric digits 20 /*allow 20-digit numbers (default is 9)*/
v= /*start with a null vector. */
do j=1 for 30 /*build an array of thirty elements. */ v=v j /*builds a vector: 1 2 3 ... 28 29 30 */ end
sum=0 /*initialize SUM to zero. */
do k=1 /*start with the first element (if any)*/ x=word(v,k) /*pick off the Kth vector element. */ if x== then leave /*if no more elements, then we're done.*/ sum =sum + x**2 /*add the squared element to the sum. */ end
say 'sum of' k-1 "elements for the V vector is:" sum </lang> Output:
sum of 30 elements for the V vector is: 9455
Ruby
<lang ruby>[3,1,4,1,5,9].inject(0) { |sum,x| sum += x*2 }</lang>
or
<lang ruby>[3,1,4,1,5,9].map { |x| x**2 }.reduce(:+)</lang>
Sather
<lang 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;</lang>
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.
<lang scala>def sum_of_squares(xs: Seq[Double]) = xs.foldLeft(0) {(a,x) => a + x*x}</lang>
Scheme
<lang scheme>(define (sum-of-squares l)
(apply + (map * l l)))</lang>
> (sum-of-squares (list 3 1 4 1 5 9)) 133
Slate
<lang slate>{1. 2. 3} reduce: [|:x :y| y squared + x]. {} reduce: [|:x :y| y squared + x] ifEmpty: [0].</lang>
Smalltalk
<lang smalltalk>#(3 1 4 1 5 9) inject: 0 into: [:sum :aNumber | sum + aNumber squared]</lang>
SNOBOL4
<lang SNOBOL4> define('ssq(a)i') :(ssq_end) ssq i = i + 1; ssq = ssq + (a * a) :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 @p :s(loop)
output = str ' -> ' sumsq(a)
end</lang>
Output:
1 2 3 5 7 11 13 17 19 23 -> 1557
Standard ML
<lang sml>foldl (fn (a, sum) => sum + a * a) 0 ints</lang>
<lang sml>foldl (fn (a, sum) => sum + a * a) 0.0 reals</lang>
SQL
<lang sql>select sum(x*x) from vector</lang>
Note that this assumes that the values in our vector are named x
.
Tcl
<lang tcl>proc sumOfSquares {nums} {
set sum 0 foreach num $nums { set sum [expr {$sum + $num**2}] } return $sum
} sumOfSquares {1 2 3 4 5} ;# ==> 55 sumOfSquares {} ;# ==> 0</lang>
<lang tcl>package require struct::list
proc square x {expr {$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</lang> Generic "sum of function" <lang tcl>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 $x}} {1 2 3 4 5} ;# ==> 55</lang>
Trith
<lang trith>[3 1 4 1 5 9] 0 [dup * +] foldl</lang>
UnixPipes
<lang bash>folder() {
(read B; res=$( 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</lang>
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, -:. <lang Ursala>#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></lang> output:
62223
V
<lang v>[sumsq [dup *] map 0 [+] fold].
[] sumsq =0 [1 2 3] sumsq</lang>
=14
Visual Basic .NET
<lang vbnet>
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
</lang> 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
- Programming Tasks
- Arithmetic operations
- ActionScript
- Ada
- ALGOL 68
- AutoHotkey
- AWK
- BASIC
- BBC BASIC
- Brat
- C
- C++
- Boost.Lambda
- C sharp
- Chef
- Clojure
- Common Lisp
- D
- Delphi
- E
- Erlang
- Euphoria
- Factor
- Fantom
- Forth
- Fortran
- F Sharp
- GAP
- Go
- Golfscript
- Groovy
- Haskell
- IDL
- Icon
- Unicon
- Inform 7
- Io
- J
- Java
- JavaScript
- Functional
- K
- Liberty BASIC
- Logo
- Logtalk
- Lua
- Mathematica
- MATLAB
- Maxima
- Modula-3
- Objeck
- OCaml
- Octave
- Oz
- PARI/GP
- Perl
- Perl 6
- PHP
- PicoLisp
- PL/I
- Pop11
- PostScript
- Initlib
- PowerShell
- PureBasic
- Python
- Prolog
- R
- REXX
- Ruby
- Sather
- Scala
- Scheme
- Slate
- Smalltalk
- SNOBOL4
- Standard ML
- SQL
- Tcl
- Tcllib
- Trith
- UnixPipes
- Ursala
- V
- Visual Basic .NET