It appears that you just forgot a ? after the second "half" of the regex. That's why it would match with two numbers but not with one.

Here's how I modified it: 

my $R = 'dounut_s12x30';
print "$1, $2\n"
  if $R !~ /^i|^ddi/ and $R =~ /^[a-z_]+(\d+\.?\d*)[a-z_]?(\d+\.?\d*)?
+/;

[download]
Outputs:
12, 30

Is this what you are asking?

Russ

In reply to RE: Regex trouble by Russ
in thread Regex trouble by cyclone

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