At the time of the dereference, the $y-th value of @aob is empty. It's certainly possible for the $y-th value to be empty when the $x-th value is not - $x just has to be less than $y. Perhaps you really mean my @row  = @{$aob[ $x ]};? This sounds very much like an indexing error. A readthrough of perlreftut/perldsc might be helpful.

Otherwise, I'll need to see your issue in broader context - a complete script with sample input and intended/desired output, all wrapped in <code> tags would be ideal.

In reply to Re^3: undefined value in array reference by kennethk
in thread undefined value in array reference by Dandello

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