column-map ( matrix quot: ( ... col -- ... col' ) -- matrix' )
Matrix operations

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Vocabulary
math.matrices

Inputs

matrix	a matrix
quot	a quotation with stack effect ( ... col -- ... col' )

Outputs

matrix'

a sequence, a matrix, or f

Word description
Apply the quotation to every column of the matrix. The output of the quotation must be a sequence.

Notes

•	This word is intended for use with "flat" (2-dimensional) matrices.
•	This word is the transpose variant of map.

Examples

USING: sequences math.matrices prettyprint ; 3 <identity-matrix> [ reverse ] column-map .
{ { 0 0 1 } { 0 1 0 } { 1 0 0 } }

Definition

USING: kernel sequences ;

IN: math.matrices

: column-map
    ( matrix quot: ( ... col -- ... col' ) -- matrix' )
    [ transpose ] dip map transpose ; inline