I don't know if this is really faster, but a bit shorter: 
sub getIntensity {
   my $mLo = $_[0] – 0.3;
   my $mHi = $_[0] + 0.3;
   my $intensity = 0;
   map { if ($_ >= $mLo && $_ <= $mHi) {
         $intesity = $massint{$_} > $intensity ? $massint{$_} : $inten
+sity}
       } keys %massint;

return $intensity;
}

[download]
hope it help's :^)

In reply to Re: speeding up a hash lookup by physi
in thread speeding up a hash lookup by chinman

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