Function fastFourierTransform
Forward or backward fast Fourier transform. Data must be power of two in length
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");