off the top of my head: 
my %hash = (-5189 => 63, -3213 => 9, -2357 => 3);

sub next_key {
  my ($h,$key) = @_;

  foreach my $hkey (sort keys %$h) {
   return $h->{$hkey} if $hkey >= $key;
  }
  return;
}
print next_key(\%hash,3000) . "\n";

[download]
but it returns null for 3000, because I believe your data is wrong. You imply that the keys should be positive. Try: 
my %hash = (5189 => 63, 3213 => 9, 2357 => 3);

[download]


-pete
"Worry is like a rocking chair. It gives you something to do, but it doesn't get you anywhere."

In reply to Re: Setting In-between values in a hash (interpolating) by dreadpiratepeter
in thread Setting In-between values in a hash (interpolating) by ravishi

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