Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hello monks!

I want to know if there's a way to round numbers in perl! like, if its 5.2 - be able to round it down or up.

5.2 -> 5 #(down)
5.2 -> 6 #(up)

Replies are listed 'Best First'.
Re: round numbers
by husoft (Monk) on Oct 07, 2002 at 16:17 UTC
    You can use the Posix module: 
    use POSIX;
print floor(5.2);            #5
print ceil(5.2);             #6

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Re: round numbers
by zigdon (Deacon) on Oct 07, 2002 at 16:20 UTC

    You could use POSIX, like husoft suggested, or use int:

    $num = 5.2;
if ($num > 0) {
  $floor = int($num);
  $ceil = int($num) == $num ? $num : int($num)+1;
} else {
  $floor = int($num) == $num ? $num : int($num)-1;
  $ceil = int($num);
}

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    Updated: updated to deal with negative numbers correctly, as rir pointed out.

    -- Dan

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      Wrong for numbers under 0.
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Re: round numbers
by BrowserUk (Patriarch) on Oct 07, 2002 at 16:22 UTC

    The POSIX module is part of the standard distribution and has both ceil and floor() functions. 

    #! perl -sw
use strict;
use POSIX;

my $n = 5.2;

print $n, ' ', POSIX::ceil($n), ' ', POSIX::floor($n), $/;

__DATA__
C:\test>203372
5.2 6 5

C:\test>

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