[推荐]任意精度计算原代码
apfloat（http://www.apfloat.org/apfloat/）A C++ High Performance Arbitrary Precision Arithmetic Package
--------------------------------------------------------------------------------
Apfloat is a high performance arbitrary precision package. That means you can do calculations involving millions of digits with it. It uses Number Theoretic Transforms. It's simple to use. It's fast. It's freeware.
A Java version is also available.
Apfloat could be compiled in general with most C++ compilers, however gcc is recommended. It has assembler optimizations for x86, Alpha and MIPS processors.
A sample program for calculating pi is included in the package. Calculating one million digits of pi takes less than half a minute with an Athlon XP computer. This makes it one of the fastest programs for calculating pi (faster than the Japanese super_pi program).
Compiled executables for calculating pi are available for download. The fastest versions of the program can calculate up to 226 million decimal digits of pi. A machine with at least 256 MB of RAM would be needed for such a calculation. A version, which can calculate up to 1.9 billion digits (if you have at least two gigabytes of memory) is also provided, but it is somewhat slower.
[ 本帖最后由 yejet 于 2006-11-13 09:19 编辑 ] <P>楼主有可以增加fortran的精度的工具不?</P>
<P>谢谢</P>
求助：怎样用matlab 产生多项分布随机数
<P>增加fortran的精度？</P><P>你是指变量的位数？</P>
<P>double precision不够你用吗</P> 你试一下这个，据说可以将fortran的数据类型扩展到很高精度的一个库函数
我还没用过
http://forum.vibunion.com/forum/viewthread.php?tid=31585 提高精度，不就取决你用的差分格式和算法么，还有别的办法么？ 还有小数点后边的位数，不过感觉有点吹毛求疵 <P>确实关键因素还是网格和算法的问题</P> <DIV class=quote><B>以下是引用<I>多情清秋</I>在2005-7-27 10:10:04的发言：</B><BR>
<P>增加fortran的精度？</P>
<P>你是指变量的位数？</P>
<P>double precision不够你用吗<BR><BR><BR>有的时候,需要更多的有效位数.<BR><BR>fortran中只带的矩阵计算如:<BR>((KXY.XI.KYY).XT.KXY)<BR>当时发现kyy的数量级达到10e9时,计算就有问题了.<BR>只好先将kyy/10e9后再在总体上乘10e9.<BR><BR></P></DIV>
<br>
页:
[1]