in reply to Re: Re: Finding Primes
in thread Finding Primes

Why not just use something like this:

#!/usr/bin/perl -wl

sub logb10 {
  return log(+shift)/log(10);
}

print int(logb10(100) + logb10(100) + 1);
print int(logb10(321) + logb10(311) + 1);
print int(logb10(321) + logb10(312) + 1);
__DATA__
output:
5
5
6

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Or maybe we could just pull out the magic length method and stop trying to focus on a problem that isn't really a problem?

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Re: Re: Re: Re: Finding Primes
by BrowserUk (Patriarch) on Aug 14, 2003 at 23:17 UTC

    It probably amounts to much the same thing, but there is a log10() function available as a part of POSIX which is in the standard distribution. 

    use POSIX qw[log10];

print log10 312;
2.49415459401844

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    Examine what is said, not who speaks.
    "Efficiency is intelligent laziness." -David Dunham
    "When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller
    If I understand your problem, I can solve it! Of course, the same can be said for you.
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