Add overloads of std:: math functions for c10::complex (#35725)
Summary:
Issue: https://github.com/pytorch/pytorch/issues/35284
~This depends on and contains https://github.com/pytorch/pytorch/pull/35524. Please review after the dependency gets merged and I will rebase to get a clean diff.~
The implementation of most functions follow the pattern
```C++
template<typename T>
C10_HOST_DEVICE c10::complex<T> some_function(c10::complex<T> x) {
#if defined(__CUDACC__) || defined(__HIPCC__)
return static_cast<c10::complex<T>>(thrust::some_function(static_cast<thrust::complex<T>>(x)));
#else
return static_cast<c10::complex<T>>(std::some_function(static_cast<std::complex<T>>(x)));
#endif
}
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/35725
Differential Revision: D21256854
Pulled By: ezyang
fbshipit-source-id: 2112ba6b79923450feafd7ebdc7184a3eaecadb6
