From: mschulter AT  DOT value DOT net (M. Schulter)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: pb with long double
Date: 15 Aug 1997 18:53:35 GMT
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Paul Derbyshire (ao950 AT FreeNet DOT Carleton DOT CA) wrote:

: Gesam (vsamou AT cict DOT fr) writes:

: > After I use GCC : gcc myprog.c -o myprog.exe -lm 
: > The result is 3.14159265358979311600 
: 
: Funny, I count 19 here. Plus those two zeros.

But are they the _right_ 19 digits <grin>?

Pi:                        3.14159265358979323846 
Result (as double):        3.14159265358979311600
Result (as long double):   3.14159265358979323851

Note that the first 16 digits in our original poster's example are correct
(as one might expect for a double), but the rest differ. 

As I noted in a previous message, when pi is defined as a long double with
a suffix 'L', it comes out accurate to 19 digits with GCC, although the
last two digits differ, as we might expect even in the case of a long
double.

Most respectfully,

Margo Schulter
mschulter AT value DOT net

(To reply, please remove the extra . in my default address)