foreach (keys %hash) {
    delete($hash{$_}) if ($_ !~ /\d+_\d+/);
}

[download]
Going to see if merlyn's example works on my version of Perl... Oh neat, it does. I think his trumps mine by a bit.

In reply to Re^3: Selecting particular key-value pairs in hashes by TedPride
in thread Selecting particular key-value pairs in hashes by kiat

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