Arrays in Perl are zero-based (generally). Look, you initialize array starting from index 1 and that means you totally leave out the first row and the first column in each of the subsequent rows.

Then sort starts to iterate on rows of your array and access their third (->[2]) element. This of course fails, as your first row is undef.

Use your Perl arrays with zero-based indices as was intended by design :)

In reply to Re: how to sort multi-dimensional arrays by kappa
in thread how to sort multi-dimensional arrays by Anonymous Monk

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