From: enlar AT hidespam DOT iname DOT com (Eneko Lacunza)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Help - Floating Point Exception
Date: Sat, 26 Sep 1998 14:42:37 +0200
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Hello Boon!

In Viernes 25 Septiembre 1998 at 11:33, Boon van der RJ wrote to All:

 >> angulo=atan2((xcont-160),(100-ycont));
 BvdR> atan2(0,0) might be handled not quite right, so that
 >>             table[xcont][ycont][1]=floor(255*angulo/(2*pi)); // FPE
 BvdR> floor crashes.

    This seemed to be the problem. I set up a check so that I hardcoded
angulo's value when atan2(0,0), and it now works allways.

 >> (i.e. running it under rhide) and if I try to redir the crash, redir
 >> crashes when the program has finished the above code and is doing
 >> something else.
 BvdR> In a dos-box under windows 95, you can mark the screen and paste in a
 BvdR> text-file, maybe that helps.

    Good point, I didn't think in it! 8-)

 >> fix it (if this info is enough). I'm using GCC 2.7.2...
 BvdR> Do you compile with -lm, or do you use the standards in libc? libm
 BvdR> does some more checking (if I've understood correctly)

    I use standards... libm is faster than standard lib?

 BvdR> What type of computer do you use? (386/486/pentiumII?)

    Plain Pentium.

    It's strange, I don't understand why it crashed under command.com but it
didn't under rhide, for example. 8-)

    Thank you very much for your *fast* help! 8-)

Regards,

Eneko Lacunza.
enlar/Genesis

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