Thank you, you must be right, but argh I can't see them... I included elsewhere some "defined" in my script such as "if (defined($variable)..." that work fine, but here I have troubles pointing uninitialized values in my matrix. I suppressed the warning with "no warnings 'uninitialized'", but it's problematic for the other errors I could get.

I tried : my @matrix_defined = grep {defined} @matrix; with no success.

In reply to Re^2: "Use of uninitialized value in pattern match (m//)" warning, doing a grep on 2D array by soblanc
in thread "Use of uninitialized value in pattern match (m//)" warning, doing a grep on 2D array by soblanc

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