#### Do you have a question? Post it now! No Registration Necessary. Now with pictures!

**posted on**

- PerlFAQ Server

November 30, 2010, 5:00 pm

comes with the standard Perl distribution. These postings aim to

reduce the number of repeated questions as well as allow the community

to review and update the answers. The latest version of the complete

perlfaq is at http://faq.perl.org .

--------------------------------------------------------------------

4.11: How do I get a random number between X and Y?

To get a random number between two values, you can use the "rand()"

built-in to get a random number between 0 and 1. From there, you shift

that into the range that you want.

"rand($x)" returns a number such that "0 <= rand($x) < $x". Thus what

you want to have perl figure out is a random number in the range from 0

to the difference between your

***X***and

***Y***.

That is, to get a number between 10 and 15, inclusive, you want a random

number between 0 and 5 that you can then add to 10.

my $number = 10 + int rand( 15-10+1 ); # ( 10,11,12,13,14, or 15 )

Hence you derive the following simple function to abstract that. It

selects a random integer between the two given integers (inclusive), For

example: "random

___int___between(50,120)".

sub random

___int___between {

my($min, $max) = @_;

# Assumes that the two arguments are integers themselves!

return $min if $min == $max;

($min, $max) = ($max, $min) if $min > $max;

return $min + int rand(1 + $max - $min);

}

--------------------------------------------------------------------

The perlfaq-workers, a group of volunteers, maintain the perlfaq. They

are not necessarily experts in every domain where Perl might show up,

so please include as much information as possible and relevant in any

corrections. The perlfaq-workers also don't have access to every

operating system or platform, so please include relevant details for

corrections to examples that do not work on particular platforms.

Working code is greatly appreciated.

If you'd like to help maintain the perlfaq, see the details in

perlfaq.pod.

#### Site Timeline

- » mp3 to .swf (flash)?
- — Next thread in » PERL Discussions

- » ANNOUNCE: NHI1-0.10, PLMK-1.8 und libmsgque-4.8
- — Previous thread in » PERL Discussions

- » s suffix question
- — Newest thread in » PERL Discussions

- » Anyone Using ESET NOD32??
- — The site's Newest Thread. Posted in » Anti-Virus Software