Or if you wanted base N (where N could be 2, π, 10, 16, etc.)... 

sub log_N
{
  my $num = shift;
  my $base = shift;
  return log($num)/log($base);
}

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In reply to Re: Get logarithm of base 10 by northwind
in thread Get logarithm of base 10 by tamaguchi

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