浮点运算，C / C ++的方法去哪儿？

Question

I'm creating a web application that does some very heavy floating point arithmetic calculations, and lots of them! I've been reading a lot and have read you can make C(and C++) functions and call them from within PHP, I was wondering if I'd notice a speed increase by doing so?

I would like to do it this way even if it's only a second difference, unless it's actually slower.

Answer 1

It all depends on the actual number of calculations you are doing. If you have thousands of calculations to do then certainly it will be worthwhile to write an extension to handle it for you. In particular, if you have a lot of data this is where PHP really fails: it's memory manager can't handle a lot of objects, or large arrays (based on experience working with such data).

If the algorithm isn't too difficult you may wish to write it in PHP first anyway. This gives you a good reference speed but more importantly it'll help define exactly what API you need to implement in a module.

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Update to "75-100 calculations with 6 numbers".

If you are doing this only once per page load I'd suspect it won't be a significant part of the overall load time (depends what else you do of course). If you are calling this function many times then yes, even 75 ops might be slow -- however since you use only 6 variables perhaps their optimizer will do a good job (whereas with 100 variables it's pretty much guaranteed not to).

Answer 2

Check SWIG .

Swig is a way to make php (and other languages) modules from your C sources rather easily.