From: "John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: long doubles and NaNs
Date: Mon, 16 Jun 1997 19:25:11 +0000
Organization: Two pounds of chaos and a pinch of salt
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References: <33A57964 DOT 4C1D AT ior DOT unizh DOT ch>
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matteotti carlo wrote:
> 
> I'm a beginner with C++ and I just started with DJGPP.
> As a little exercise I've written a stupid little "program" which
> should read a "real number" as a long double and write this number
> back to the screen again. But what I get back is just "-NaN".
> How can I convince the program that e.g. 1.13245  is indeed a number ??

Can you post sample code?  Specifically, how are you declaring the
variable, how are you passing it to scanf(), and how are you printing
it?  Here's an example:

#include <stdio.h>

int main( void )
{
    long double ld;

    printf( "Enter a decimal number:  " );
    if ( scanf( "%Lf", &ld ) == 1 )
        printf( "You entered %Lf.\n", ld );
    else
        printf( "That's not a number.\n" );

    return 0;
}

P.S.:  Please post general programming questions on comp.lang.c or
comp.lang.c.moderated, or get a good C reference book.

hth

-- 
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|      John M. Aldrich       | "Sex should be friendly.  Otherwise  |
|       aka Fighteer I       | stick to mechanical toys; it's more  |
|   mailto:fighteer AT cs DOT com   | sanitary."                           |
| http://www.cs.com/fighteer |                - Lazarus Long        |
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