Question

How I could convert array of type short to array of type double in C/C++?

I have code to read audio data from wav file and output is array of type short. So now I want to use this data for FFT (I don’t want use libraries).

Any tricks or ideas?

Answer 1

You can’t convert the array; you can however create a new array with the converted values:

#include <iterator>
#include <algorithm>

short src[10] = ...;

double dst[sizeof(src)/sizeof(short)];

std::copy(std::begin(src), std::end(src), dst);  // generic, C++11
std::copy(src, src + 10, dst);                   // a bit more hackish

Even better would be to use std::array<float, 10> src; etc.

If your “arrays” are really dynamic data structures, it becomes even easier:

std::vector<float> src = ... ;
std::vector<double> dst(src.begin(), src.end());