sum ( seq -- n )
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Vocabulary
sequences

Inputs

seq	a sequence of numbers

Outputs

n

a number

Word description
Outputs the sum of all elements of seq. Outputs zero given an empty sequence.

Examples

USING: prettyprint sequences ; { 3 1 5 } sum .
9

USING: prettyprint sequences ; { } sum .
0

Definition

IN: sequences

GENERIC: sum ( seq -- n )

Methods

USING: math sequences sequences.cords ;

M: cord sum [ sum ] cord-both + ; inline


USING: kernel math sequences ;

M: iota sum length dup 1 - * 2/ ; inline


USING: kernel math sequences ;

M: object sum 0 [ + ] binary-reduce ; inline


USING: kernel math ranges sequences sequences.private ;

M: range sum
    dup length
    [ drop 0 ]
    [ swap [ first-unsafe ] [ last-unsafe ] bi + * 2 / ] if-zero
    ;


USING: accessors kernel math sequences ;

M: repetition sum [ elt>> ] [ length>> ] bi * ; inline


USING: generic kernel math.vectors.simd
math.vectors.simd.intrinsics math.vectors.simd.private sequences
;

M: simd-128 sum
    dup simd-rep
    [ (simd-sum) ] [ M\ simd-128 sum (call-next-method) ]
    v->x-op ; inline


USING: accessors kernel math sequences tensors tensors.private ;

M: tensor sum
    vec>> 0 <simd-slice>
    [ simd-slice>> [ sum ] map-sum ] [ end-slice>> sum ] bi + ;