#!/usr/bin/env raku
#| dot product of two vectors
sub infix:<·>( @a, @b where @a.elems == @b.elems ) {
[+] @a >>*<< @b
}
#| generic matrix multiplication - cols of @a must equal rows of @b
sub infix:<dot>( @a, @b where @a[0].elems == @b>>.[0].elems) {
my @b-transposed = [Z] @b;
my UInt $degree = %*ENV<RAKU_PARALLEL_COMPUTATION_DEGREE> // 2;
my UInt $batch = %*ENV<RAKU_PARALLEL_COMPUTATION_BATCH_SIZE> // 2 ** 15;
note "Parallel computation using $degree cores and a batch size of $batch elements" if %*ENV<RAKU_PARALLEL_COMPUTATION_DEBUG>;
@a.hyper(:$degree, :$batch).map( -> @r { @b-transposed.map( -> @c { @r · @c } ) })
}
use Test;
plan 1;
my @a =
[1, 0, 1],
[2, 1, 1],
[0, 1, 1],
[1, 1, 2],
;
my @b =
[1, 2, 1],
[2, 3, 1],
[4, 2, 2],
;
my @c =
[ 5, 4, 3],
[ 8, 9, 5],
[ 6, 5, 3],
[11, 9, 6],
;
#%*ENV<RAKU_PARALLEL_COMPUTATION_DEBUG> = 1;
#%*ENV<RAKU_PARALLEL_COMPUTATION_DEGREE> = 4;
#%*ENV<RAKU_PARALLEL_COMPUTATION_BATCH> = 2 ** 21;
is @a dot @b, @c, "Matrix multiplication example from Wikipedia";
done-testing;
