Matrix transposition: Difference between revisions

{{Works with|rakudo|2018.03}}

<lang perl6># Transposition can be done with the reduced zip meta-operator

# on list-of-lists data structures

say [Z] (<A B C D>, <E F G H>, <I J K L>);

# For native shaped arrays, a more traditional procedure of copying item-by-item

# Here the resulting matrix is also a native shaped array

my @a[3;4] =

[

[<A B C D>],

[<E F G H>],

[<I J K L>],

];

(my $n, my $m) = @a.shape;

my @b[$m;$n];

for ^$m X ^$n -> (\i, \j) {

@b[i;j] = @a[j;i];

}

say @b;</lang>

<pre>((A E I) (B F J) (C G K) (D H L))

[[A E I] [B F J] [C G K] [D H L]]</pre>