When you use the assignment @vars=( @days, @cols);, you flatten both arrays into a single list, which gets copied to @vars, as you have observed. The assignment @vars=( \@days, \@cols);, on the other hand, creates an array of array references, with the power to modify the original arrays as desired so long as you take the extra depth into account. You can visualize this data with the core module Data::Dumper (See How can I visualize my complex data structure?). The basic way to accomplish this would be to simply use nested foreach loops: 

for my $array_ref (@vars) {
    s/e/E/g for @$array_ref;
}
foreach (map @$_, @vars) {
    print "$_\n";
}

[download]

For details on using references, give perlreftut a read.

In reply to Re: Regex's and Multidimensional Arrays by kennethk
in thread Regex's and Multidimensional Arrays by Mad_Mac

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