v+- ( u v -- w )
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Vocabulary
math.vectors

Inputs

u	a sequence of numbers
v	a sequence of numbers

Outputs

w	a sequence of numbers

Word description
Adds and subtracts alternate elements of v and u component-wise. Elements at even indexes are subtracted, while elements at odd indexes are added.

Examples

USING: math.vectors prettyprint ; { 1 2 3 } { 2 3 2 } v+- .
{ -1 5 1 }

Definition

IN: math.vectors

GENERIC: v+- ( u v -- w )

Methods

USING: generic math.vectors sequences.cords ;

M: cord v+-
    [ v+- ] [ M\ cord v+- (call-next-method) ] cord-2map ;
    inline


USING: kernel math math.vectors sequences ;

M: object v+-
    [ t ] 2dip [ [ not ] 2dip pick [ + ] [ - ] if ] 2map nip ;
    inline


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

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