AppleFritter already gave you the docs, just to add to that: DATA doesn't directly relate to your problem, it was just a quick way to show an example of what the warning message might look like. The data can very well reside in a file and the messages would be almost the same.

In reply to Re^3: Find data point generating Error in Perl code by Anonymous Monk
in thread Find data point generating Error in Perl code by kgherman

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