Hmm, based on your expectation for your data, I'm guessing what you probably need is to add: 
next unless ref( $data{$id}[$window] ) eq "ARRAY";

[download]
just before the line getting the error.

In reply to Re^4: Population of HoAoA based on file contents by state-o-dis-array
in thread Population of HoAoA based on file contents by iangibson

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