From:	Joe Wright <wrightj AT exis DOT net>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Problems with DJGPP V2.01 - atof() function
Date:	Sun, 01 Dec 1996 03:25:10 -0500
Organization:	Alpha Solutions
Lines:	44
Message-ID:	<32A140E6.7172@exis.net>
References:	<329e68a5 DOT 10316617 AT news DOT ua DOT pt> <57mtq1$4mo AT vidar DOT diku DOT dk> <32A02DD1 DOT 1157 AT pobox DOT oleane DOT com>
Reply-To:	wrightj AT exis DOT net
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Francois Charton wrote:
> 
> Morten Welinder wrote:
> >
> > afonso AT inesca DOT inesca DOT pt writes:
> >
> > >                char string[]="1.13";
> > >                int  result;
> > >                ...
> > >                result = (int)(atof(string)*100);
> > >                ...
> >
> > >        I've got result = 112!!! not 113 as I wished, because
> > >the function atof() return is 1.29999... not 1.13 (and I only have
> > >an old i386).
> >
> > Getting 112 is well within the C standard.  If your program does
> > not work in this situation then you have a bug.
> >
> 
> Sorry to disagree but this *is* a bug : to be sure try the following
> program :
> 
> int main(void)
> {
> char ch[8]="1.13";
> int result, otherresult;
> float f;
> result=(int)(atof(ch)*100.0);
> f=atof(ch)*100.0;
> otherresult=(int) f;
> printf("result: %d otherresult:%d\n", result, otherresult);
> return 0;
> }
> 
> On my machine I get result: 112 and otherresult: 113...
> 
> Francois

Not me.  I get 112 in all cases.  The right way is probably
result = (int)(ceil(atof(ch)*100));
which gives 113.

Joe

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