From:	Jason Green <news AT jgreen4 DOT fsnet DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Iostream question
Date:	Wed, 02 May 2001 23:46:16 +0100
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Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de> wrote:

> Rafal Maj <maj_rafal AT poczta DOT onet DOT pl> wrote:

> > following code :
> >   long double r =
> > 3.1415012345678901111112222233333444445555666677777888899999000012345;
> >   cerr << setprecision(999) << r;
> > displays in cerr only : 3.1415012345678903

Hmmm, interesting bug.

#include <iostream>
#include <iomanip>

int main()
{
  long double r =

3.1415012345678901111112222233333444445555666677777888899999000012345;

  int i;
	
  for (i=1; i<2000; i++)
    cerr << i << " " << setprecision(i) << r << endl;
}

> > How to display (or write to file) long double with full precision using
> > iostream ? 

Try setprecision(998) or setprecision(1000)  :-)

> Or does long double hold only 16 digits of my variable ?

It will hold more than that, but not necessarily the exact value that you
assign it.

> Try:
> 
>   long double r = 3.1415012345678901111112222233333L;

>        [#4]  An  unsuffixed  floating constant has type double.  If
>        suffixed by the letter f  or  F,  it  has  type  float.   If
>        suffixed by the letter l or L, it has type long double.

Well if that's what the standard says... ;-).  FWIW, adding the L suffix
seems to make no difference.

Roll on gcc 3.0.

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