Function fastFourierTransform

Forward or backward fast Fourier transform. Data must be power of two in length

void fastFourierTransform (
  Complex!(float)[] data,
  bool forward
);

Example

Complexf[4] data =
[
    Complexf(1.0f, 0.0f),
    Complexf(2.0f, 0.0f),
    Complexf(3.0f, 0.0f),
    Complexf(4.0f, 0.0f)
];

fastFourierTransform(data, true);

assert(data[0].toString == "10 + 0i");
assert(data[1].toString == "-2 + 2i");
assert(data[2].toString == "-2 + 0i");
assert(data[3].toString == "-2 + -2i");