... error in my code ...

As others have replied, it's not an error, it's a warning (see warnings, which you have wisely enabled in your program).

Where is it? The only line in the quoted code that does concatenation (or string interpolation, which is effectively the same thing) is
    print PLP_FILE   "$aa_pos\t".$split_query_for_PLP[$s]."\t".$hash_plp_lbl_barrel_region_only{$s}."\n";

It seems unlikely to be $aa_pos. My suspicious eye is drawn to the
    $s<=(($start_of_barrel_region+$length_of_barrel_region))
expression in the for-loop test: is it possible you have an off-by-one error here? E.g., if  $start_of_barrel_region were 0 and  $length_of_barrel_region were the number of elements in the  @split_query_for_PLP array, would not the  <= comparison allow an index to be generated that was one element beyond the end of the array, and thus undefined? (I don't know about the rest of your code, and so don't know if anything like this could happen.) Just a guess.

Is it severe? If you are operating on meaningless data that you believe to be meaningful, it's severe.

Give a man a fish:  <%-(-(-(-<

In reply to Re: Is this a severe error? by AnomalousMonk
in thread Is this a severe error? by Anonymous Monk

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