This returns a new F64 instance with the given parameters.
It makes sense to keep one instance for several calls for speed reasons.
len
must be even and to get the best performance a product of 2, 3 and 5. To get the next number with this characteristics
use fft_next_fast_length.
len |
Length of the FFT in the time domain |
inverse |
true if the F64 instance should be used for the inverse FFT |
a new F64 instance. |