Path: chuka.playstation.co.uk!news
From: "pal" <palpalpalpal@hotmail.com>
Newsgroups: scee.yaroze.freetalk.english
Subject: Re: rand ()
Date: 13 Mar 2004 10:18:42 GMT
Organization: PlayStation Net Yaroze (SCEE)
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Nigel Critten <Nigel@100tinsoldiers.com> wrote in article
<c2t4oa$5lq9@www.netyaroze-europe.com>...
> Does anyone have a rand function that will generate a random number 
> between two given numbers so rand (-10, 10) would generate a number 
> somewhere between -10 and 10, the built in rand () returns a number 
> between 0 - 32767 which doesn't help much.

I believe most people, including myself, use it that way:
(rand() % 21) - 10
where 21 is (10 - -10) + 1.

you might want to check whether the bounds are properly included, depending
on what you need. I think this code would give something in [-10, +10].

A generic function may looke like:
int my_rand(low, high) {
   return rand() % (high - low + 1) + low;
}

Note that % is costly, in case you want to do it a lot.