长双

broli写道：

broli wrote:

这是C 99的一部分，还是像某些windows编译器中的一个插件，比如

pellesC？

Is this a part of C 99 or just an addon in some windows compilers like
pellesC ?

它已成为所有C语言标准的一部分：ISO C90，C95，C99。

It has been a part of all C language standards: ISO C90, C95, C99.

" broli" < Br ***** @ gmail.com在消息新闻中写道：

"broli" <Br*****@gmail.comwrote in message news:

这是C 99的一部分，还是某些Windows编译器中的插件，如

pellesC？

Is this a part of C 99 or just an addon in some windows compilers like
pellesC ?

基本上这是一个硬件问题。虽然可以在

软件中模拟浮点数，但如果必须这样做，则不太可能需要更高的精度。

如果硬件支持80位浮点数在实践中，C编译器必须支持

，否则人们会抱怨。我认为这实际上是它的价值的一部分，但这个标准还没有被广泛接受，

所以它不是真的很重要，不论是否加倍。


-

免费游戏和编程好东西。
http://www.personal.leeds.ac.uk/~bgy1mm

Basically it''s a hardware question. Whilst floating point can be emulated in
software, if you have to do this it''s unlikely that you need much precision.
If the hardware supports 80 bit floats then the C compiler has to support
them, in practise, or people would complain. I think it is actually part of
C99, for what it''s worth, but that standard hasn''t received wide acceptance,
so it doesn''t really matter whether long double is in it or not.

--
Free games and programming goodies.
http://www.personal.leeds.ac.uk/~bgy1mm

Malcolm McLean写道：

Malcolm McLean wrote:

" broli" < Br ***** @ gmail.com在消息新闻中写道：

"broli" <Br*****@gmail.comwrote in message news:

>这是C 99的一部分，还是像某些Windows编译器中的插件一样
pellesC？

>Is this a part of C 99 or just an addon in some windows compilers like
pellesC ?

基本上这是硬件问题。虽然可以在

软件中模拟浮点数，但如果必须这样做，则不太可能需要更高的精度。

如果硬件支持80位浮点数在实践中，C编译器必须支持

，否则人们会抱怨。我认为这实际上是它的价值的一部分，但这个标准还没有被广泛接受，

所以它不是真的很重要，不论是否有长双。

Basically it''s a hardware question. Whilst floating point can be emulated in
software, if you have to do this it''s unlikely that you need much precision.
If the hardware supports 80 bit floats then the C compiler has to support
them, in practise, or people would complain. I think it is actually part of
C99, for what it''s worth, but that standard hasn''t received wide acceptance,
so it doesn''t really matter whether long double is in it or not.

你似乎对长双意味着什么感到困惑。没有

要求长两倍至少为80位。虽然很长的双倍

是C99的一部分，但不能保证更大或存储更多

值而不是双倍。


菲利普

You seem to be confused about what ''long double'' means. There is no
requirement that long double be at least 80 bits. Although long double
is part of C99, it is not guaranteed to be any larger or store any more
values than double.

Philip