From: Konstanty <M DOT Bialkowski AT mailbox DOT uq DOT edu DOT au>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Significant Digits
Date: Wed, 15 Apr 1998 09:56:58 +1000
Organization: University of Queensland
Lines: 27
Message-ID: <3533F7CA.A4F473C3@mailbox.uq.edu.au>
References: <35338A5C DOT D17E22CA AT e-z DOT net>
Reply-To: M DOT Bialkowski AT mailbox DOT uq DOT edu DOT au
NNTP-Posting-Host: csmbialk.staff.uq.edu.au
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Precedence: bulk

I think that a 'double' has more than 7 sig figures.
If you need many significant figures use a 'long double' which has around 41
sig fig.

you use:
 printf("%.41Lf\n",a);
which shows 41 decimal places in Long Float mode to see them all, 7 i think
is the default setting.

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.
>
> Thanks,
> Albert