Non-destructively: 

  my %hash2 = map  {$_ => $hash{$_}}
              grep {/^\d+_\d+$/}
              keys %hash;

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pbeckingham - typist, perishable vertebrate.

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

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