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D - D floating point

reply John Fletcher <J.P.Fletcher aston.ac.uk> writes:
I am experimenting with this.

I can do

extended x = 1.;
printf("%lf\n",(double)x);

It needs the cast to get the correct answer.

I was trying to do sprintf() to put it into a buffer, but sprintf would
not compile.

John
Jan 25 2002
parent reply Russell Borogove <kaleja estarcion.com> writes:
John Fletcher wrote:


 extended x = 1.;
 printf("%lf\n",(double)x);
 
 It needs the cast to get the correct answer.




My guess is that, since printf is currently coming from a C
library, its floating point support is going to match that
of the C implementation.

A reading of the Digital Mars C library docs suggest
you might try a capital L in the format spec:

printf( "%Lf\n", x );

...but that's just a guess on my part.

-Russell B
Jan 25 2002
parent reply "Walter" <walter digitalmars.com> writes:
Yes, you need the Lf for "long double", which matches D's
"extended". -Walter

Why doesn't sprintf work for you? I use it!

"Russell Borogove" <kaleja estarcion.com> wrote in message
news:3C51A3B4.5030602 estarcion.com...

 John Fletcher wrote:


 extended x = 1.;
 printf("%lf\n",(double)x);

 It needs the cast to get the correct answer.




 My guess is that, since printf is currently coming from a C
 library, its floating point support is going to match that
 of the C implementation.

 A reading of the Digital Mars C library docs suggest
 you might try a capital L in the format spec:

 printf( "%Lf\n", x );

 ...but that's just a guess on my part.

 -Russell B
Jan 25 2002
next sibling parent John Fletcher <J.P.Fletcher aston.ac.uk> writes:
Walter wrote:


 Yes, you need the Lf for "long double", which matches D's
 "extended". -Walter



Thank you.


 Why doesn't sprintf work for you? I use it!



I don't know, I couldn't get it to compile, so I dug in the phobos code
and saw an example. I'll look again.

Thanks for the answer, Walter and Russell.

John
Jan 28 2002
prev sibling parent reply John Fletcher <J.P.Fletcher aston.ac.uk> writes:
Walter wrote:


 Yes, you need the Lf for "long double", which matches D's
 "extended". -Walter

 Why doesn't sprintf work for you? I use it!



Walter

I can get sprintf to work as long as I don't have printf as well, when I
get a conflict of definitions of printf between object.printf and
stdio.printf.

John
Jan 28 2002
parent "Walter" <walter digitalmars.com> writes:
Just comment out one of them. I'll fix it at my end. -Walter

"John Fletcher" <J.P.Fletcher aston.ac.uk> wrote in message
news:3C55262C.57E5ABB1 aston.ac.uk...

 Walter wrote:


 Yes, you need the Lf for "long double", which matches D's
 "extended". -Walter

 Why doesn't sprintf work for you? I use it!



 Walter

 I can get sprintf to work as long as I don't have printf as well, when I
 get a conflict of definitions of printf between object.printf and
 stdio.printf.

 John
Jan 28 2002