FFT for ndarrays
var zeros = require"zeros"var ops = require"ndarray-ops"var fft = require"ndarray-fft"var x = opsrandomzeros256 256y = opsrandomzeros256 256//Forward transform x/yfft1 x y//Invert transformfft-1 x y
npm install ndarray-fft
Executes a fast Fourier transform on the complex valued array x/y.
dir- Either +/- 1. Determines whether to use a forward or inverse FFT
xthe real part of the signal, encoded as an ndarray
ythe imaginary part of the signal, encoded as an ndarray
y are transformed in place.
Note This code is fastest when the components of the shapes arrays are all powers of two. For non-power of two shapes, Bluestein's fft is used which is somewhat slower.
Note2 The inverse FFT is scaled by 1/N, forward FFT is unnormalized.
(c) 2013 Mikola Lysenko. MIT License.
Radix 2 FFT based on code by Paul Bourke.