From:	"J.W. Dare" <jwdare AT novia DOT net>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: DBL_EPSILON
Date:	15 Nov 2001 10:36:05 -0600
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On Thu, 15 Nov 2001 06:43:08 GMT, Martin Ambuhl
<mambuhl AT earthlink DOT net> wrote:

>"J.W. Dare" wrote:
>> 
>> Can someone tell me the value of DBL_EPSILON defined in float.h.
>
>You can:
>
>#include <float.h>
>#include <stdio.h>
>
>int main(void)
>{
>   printf("DBL_EPSILON is %.*g\n", DBL_DIG, DBL_EPSILON);
>   return 0;
>}

Thank you.  

I'm writing in C++ and I wasn't sure of what value to pass to
setprecision()in order to obtain a reliable answer.  May I conclude
then that DBL_DIG is the number of significant digits of accuracy for
a type double?  

As an aside, I'm not yet familiar with precision issues concerning
floating point numbers.  Can someone point me in the direction of a
good book or web page that discusses this information? 
-- 
J.W.Dare
jwdare AT novia DOT net

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