From: "John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Significant Digits
Date: Tue, 14 Apr 1998 18:21:53 -0400
Organization: Two pounds of chaos and a pinch of salt.
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Albert Bae wrote:
> 
> Hello,
> 
>    I am making a program that needs high precision because it has to
> numerically integrate a function twice.  I beleive that the double data
> type only gives 7 significant figures.  7 sig. figs. cause a round off
> error that is to large to be acceptable as an output for my program.  I
> was wondering if there was a way of increasing the number of significant
> digits that DJGPP can handle.  If I have made any mistakes in what I
> have said please feel free to correct me.  I appreciate any help that
> you can give.

Type double should have a lot more than seven significant digits!  Check
to make sure that you've:

 - prototyped the math functions by including math.h
 - linked with the math library ('-lm')
 - not used any code that implicitly demotes double to float

If none of this helps, you could try using 'long double', or maybe even
post some sample code and the (incorrect) results you get from it.

-- 
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|      John M. Aldrich       | "A woman is not property, and hus-   |
|       aka Fighteer I       | bands who think otherwise are living |
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