This is a sort of crude first crack at it to get you started. I haven't accounted for having an array that doesn't have some multiple of three elements. 

use 5.010;

foreach my $n ( 0 .. $#array/3 ) {
    my $i = $n * 3;
    say join q{,}, @array[ $i, $i+1, $i+2 ];
}

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In reply to Re: Group array in threes by kyle
in thread Group array in threes by joec_

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