sub getIntensity {
   my $mLo = $_[0] – 0.3;
   my $mHi = $_[0] + 0.3;
   my $intensity = 0;
   map { if ($_ >= $mLo && $_ <= $mHi) {
         $intesity = $massint{$_} > $intensity ? $massint{$_} : $intensity}
       } keys %massint;

return $intensity;
}