如何减少C / C ++浮点舍入 [英] How to reduce C/C++ floating-point roundoff

问题描述

是否有任何通用的提示可以减少C或C ++中浮点舍入错误的累积？我主要考虑如何编写能够编译成最佳汇编语言指令的代码，尽管整体算法设计的策略也是受欢迎的。 解决方案

我知道的唯一技巧是，当你总结一堆数字的时候，不要一次一个地把它们组合起来，把它们加在一起，以便增加的数量大致相同。例如，总结一个庞大的随机数列，按递归方式求和。

Are there any generally-applicable tips to reduce the accumulation of floating-point roundoff errors in C or C++? I'm thinking mainly about how to write code that gets compiled into optimal assembly language instructions, although strategies on overall algorithm design are also welcome.

解决方案

The only trick I know is that when you're summing a bunch of numbers, don't do them one at a time - group them so that the additions are on numbers of approximately the same magnitude. To sum a huge array of random numbers for example, recursively sum by pairs.

这篇关于如何减少C / C ++浮点舍入的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！