I'm not quite sure what you're asking, but maybe this will give some insight: 

Win8 Strawberry 5.8.9.5 (32)  Wed 05/11/2022 18:46:44
C:\@Work\Perl\monks
>perl

use strict;
use warnings;

use Data::Dump qw(dd);

my @matrix = (
    [ qw(00 01 02 03) ],
    [ qw(10 11 12 13) ],
    [ qw(20 21 22 23) ],
    [ qw(30 31 32 33) ],
    [ qw(40 41 42 43) ],
    [ qw(50 51 52 53) ],
    );
# dd \@matrix;  # for debug

my @row_set = (0, 2);
my @col_set = (3, 0, 1);

for my $ar_entry (@matrix[ @row_set ]) {
    printf "'%s' '%s' '%s' \n", @{$ar_entry}[ @col_set ];
    }

for my $i_row (@row_set) {
    printf "row %d: '%s' '%s' '%s' \n", $i_row, @{ $matrix[$i_row] }[ 
+@col_set ];
    }

my @sub_matrix = map { [ @{ $_ }[ @col_set ] ] } @matrix[ @row_set ];
# my @sub_matrix = map [ @{ $_ }[ @col_set ] ], @matrix[ @row_set ];
dd \@sub_matrix;

^Z
'03' '00' '01'
'23' '20' '21'
row 0: '03' '00' '01'
row 2: '23' '20' '21'
[["03", "00", "01"], [23, 20, 21]]

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Give a man a fish:  <%-{-{-{-<

In reply to Re^9: reading a JSON object by AnomalousMonk
in thread reading a JSON object by anautismobserver

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