From:	Damian Yerrick <Bullcr_pd_yerrick AT hotmail DOT comRemoveBullcr_p>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Random numbers
Organization:	Pin Eight Software http://pineight.8m.com/
Message-ID:	<cs95jscumbafalh5jj0f8l6dm1u0uiq5o5@4ax.com>
References:	<392CB951 DOT 34B432E6 AT chemistry DOT uq DOT edu DOT au> <Pine DOT SUN DOT 3 DOT 91 DOT 1000525084705 DOT 21360M-100000 AT is>
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Date:	Mon, 29 May 2000 17:30:06 GMT
To:	djgpp AT delorie DOT com
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On Thu, 25 May 2000 08:49:55 +0300 (IDT), Eli Zaretskii
<eliz AT is DOT elta DOT co DOT il> wrote:

>The recommended way to generate random numbers from a smaller range is
>described in section 22.23 of the DJGPP FAQ list, which see.

The FAQ entry describes the "rescaling" technique:

#include <stdlib.h>

int random_number =
    low + (double)rand () * (high - low + 1) / RAND_MAX;

When I do this on my target platform (386 PC), the cast to double
produces SIGNOFPE.  Including emu387.dxe and emu387.bat (a script
to insert the required environment variables) fixed it.
  @ECHO OFF
  SET 387=N
  SET EMU387=C:\PINEIGHT\EMU387.DXE

Does this mean I have to bundle emu387.dxe with all programs that use
random numbers?  Or can I do this to get rid of the unrandom low-order
bits?
  nextPiece = (rand() >> 4) % 5;

-- 
Damian Yerrick
"I refuse to listen to those who refuse to listen to reason."
See the whole sig: http://www.rose-hulman.edu/~yerricde/sig.html

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