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6.14.1 Fast Fourier Transform
array-axis-fft
array-axis-inverse-fft
array-fft
array-inverse-fft

6.14 Other Array Operations

6.14.1 Fast Fourier Transform

procedure

(array-axis-fft arr k)  (Array Float-Complex)

  arr : (Array Number)
  k : Integer
Performs a discrete Fourier transform on axis k of arr. The length of k must be an integer power of two. (See power-of-two?.) The scaling convention is determined by the parameter dft-convention, which defaults to the convention used in signal processing.

The transform is done in parallel using max-math-threads threads.

procedure

(array-axis-inverse-fft arr k)  (Array Float-Complex)

  arr : (Array Number)
  k : Integer
The inverse of array-axis-fft, performed by parameterizing the forward transform on (dft-inverse-convention).

procedure

(array-fft arr)  FCArray

  arr : (Array Number)
Performs a discrete Fourier transform on each axis of arr using array-axis-fft.

procedure

(array-inverse-fft arr)  FCArray

  arr : (Array Number)
The inverse of array-fft, performed by parameterizing the forward transform on (dft-inverse-convention).