in reply to How do I extract the value from this string...?

Looks like you have a newline in your string, but that shouldn't matter ... i would use a character class that catches 0 through 9 and the dot: 
my $str    = "blah blah\nlast message 4.453 ms after\n";
my ($numb) = $str =~ /([0-9.]+)/;
print $numb, "\n";

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jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

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