this worked out very nice. Thank you very much. A bit puzzled though..

I understand that for my $i (keys %from_to_bytes) {should be read as: for all members of the family (Fred, Wilma and so on).

However I remain in trouble reading the remaining two lines:

for my $j (keys %{ $from_to_bytes{$i} }) {
        $total_col{$j} += $from_to_bytes{$i}->{$j};

[download]
It works but I'd like to understand as well.

Using hashes maybe efficient, learning how to use them takes some time for me.

Gert

In reply to Re^2: matrix - creating total row/column by GertMT
in thread matrix - creating total row/column by GertMT

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