Hi

I got bitten by the fact that log is producing a float

by definition (see log )

sub log10 {
        my $n = shift;
        return log($n)/log(10);
    }

[download]

but

  DB<36> $num = 1e12

  DB<37> $log10 = log($num)/log(10)

  DB<38> p $log10
12                              # Looks good, right? 
  DB<39> p $log10 % 3
2                               # surprise!
  DB<40> p int($log10)
11                              # Oh one of Perl's DWIM show Float as 
+Integer
  DB<41>

[download]

instead of resorting to tricks like secretly rounding up the hidden float, is there a recommended library?

Probably POSIX something?

update

clarification, I'm interested to get the log10 of a whole number.

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

In reply to Clean log_10 ? by LanX

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