我不时地读到Fortran在繁重的计算中比C更快。这是真的吗?我必须承认我几乎不懂Fortran,但是到目前为止我看到的Fortran代码并没有显示出该语言具有C语言所不具备的特性。

如果是真的,请告诉我原因。请不要告诉我什么语言或库适合处理数字,我不打算写一个应用程序或库来做这个,我只是好奇。


当前回答

大多数帖子已经提出了令人信服的论点,所以我只是在另一个方面加上众所周知的2美分。

在处理能力方面,fortran更快或更慢是有其重要性的,但如果用fortran开发一些东西需要5倍多的时间,因为:

it lacks any good library for tasks different from pure number crunching it lack any decent tool for documentation and unit testing it's a language with very low expressivity, skyrocketing the number of lines of code. it has a very poor handling of strings it has an inane amount of issues among different compilers and architectures driving you crazy. it has a very poor IO strategy (READ/WRITE of sequential files. Yes, random access files exist but did you ever see them used?) it does not encourage good development practices, modularization. effective lack of a fully standard, fully compliant opensource compiler (both gfortran and g95 do not support everything) very poor interoperability with C (mangling: one underscore, two underscores, no underscore, in general one underscore but two if there's another underscore. and just let not delve into COMMON blocks...)

那么这个问题就无关紧要了。如果某样东西很慢,大多数时候你无法在给定的限制范围内改进它。如果你想要更快,改变算法。最后,使用电脑的时间很便宜。人类的时间不是。珍惜减少人类时间的选择。如果它增加了使用电脑的时间,无论如何它都是有成本效益的。

其他回答

I was doing some extensive mathematics with FORTRAN and C for a couple of years. From my own experience I can tell that FORTRAN is sometimes really better than C but not for its speed (one can make C perform as fast as FORTRAN by using appropriate coding style) but rather because of very well optimized libraries like LAPACK (which can, however, be called from C code as well, either linking against LAPACK directly or using the LAPACKE interface for C), and because of great parallelization. On my opinion, FORTRAN is really awkward to work with, and its advantages are not good enough to cancel that drawback, so now I am using C+GSL to do calculations.

大多数帖子已经提出了令人信服的论点,所以我只是在另一个方面加上众所周知的2美分。

在处理能力方面,fortran更快或更慢是有其重要性的,但如果用fortran开发一些东西需要5倍多的时间,因为:

it lacks any good library for tasks different from pure number crunching it lack any decent tool for documentation and unit testing it's a language with very low expressivity, skyrocketing the number of lines of code. it has a very poor handling of strings it has an inane amount of issues among different compilers and architectures driving you crazy. it has a very poor IO strategy (READ/WRITE of sequential files. Yes, random access files exist but did you ever see them used?) it does not encourage good development practices, modularization. effective lack of a fully standard, fully compliant opensource compiler (both gfortran and g95 do not support everything) very poor interoperability with C (mangling: one underscore, two underscores, no underscore, in general one underscore but two if there's another underscore. and just let not delve into COMMON blocks...)

那么这个问题就无关紧要了。如果某样东西很慢,大多数时候你无法在给定的限制范围内改进它。如果你想要更快,改变算法。最后,使用电脑的时间很便宜。人类的时间不是。珍惜减少人类时间的选择。如果它增加了使用电脑的时间,无论如何它都是有成本效益的。

Fortran可以非常方便地处理数组,特别是多维数组。在Fortran中对多维数组元素进行切片比在C/ c++中容易得多。c++现在有库可以做这项工作,比如Boost或Eigen,但它们毕竟是外部库。在Fortran中,这些函数是固有的。

对于开发来说,Fortran是更快还是更方便主要取决于您需要完成的工作。作为地球物理的科学计算人员,我用Fortran(我指的是现代Fortran, >=F90)进行了大部分计算。

Fortran和C语言在特定目的上并没有哪一种语言比另一种更快。对于每种语言的特定编译器,有些编译器比其他编译器更适合某些任务。

多年来,Fortran编译器一直存在,它可以对你的数字例程施黑魔法,使许多重要的计算变得异常快速。当代的C编译器无法做到这一点。因此,在Fortran中出现了许多伟大的代码库。如果您想要使用这些经过良好测试的、成熟的、出色的库,就需要使用Fortran编译器。

我的非正式观察表明,如今人们用任何古老的语言来编码他们繁重的计算内容,如果这需要一段时间,他们就会在一些廉价的计算集群上找到时间。摩尔定律让我们所有人都成了傻瓜。

Fortran有更好的I/O例程,例如隐含的do工具提供了C标准库无法比拟的灵活性。

Fortran编译器直接处理更复杂的 涉及到语法,而且这样的语法不能轻易简化 参数传递形式,C不能有效地实现它。