Re: [Boost-users] [math][special_functions] Why is cbrt(x) slowerthan pow(x, 1/3)?

Thanks a lot for the suggestion: I didn't know that std::cbrt() exists!

There's no std:: version until the next C++ std comes out, some compilers have a version in global namespace as part of their C99 and POSIX support, others such as msvc do not.

I alway relied on cplusplus.com as reference; I will have to change that! Of course this is again a lot faster:

average time to compute 5000000 roots with pow(): 0.613 s. average time to compute 5000000 roots with cbrt(): 0.464 s.

Thanks again - I am happy now... ;-)

Hopefully the Boost version will be able to match this soon... the limiting factor at present seems to be the performance of frexp/ldexp which are particularly bad on msvc :-( John.