Data.Array.Repa.Algorithms.FFT

Fast computation of Discrete Fourier Transforms using the Cooley-Tuckey algorithm. Time complexity is O(n log n) in the size of the input.

This uses a naive divide-and-conquer algorithm, the absolute performance is about 50x slower than FFTW in estimate mode.

Documentation

data Mode

Constructors

Forward

Reverse

Inverse

Instances

Eq Mode

Show Mode

isPowerOfTwo :: Int -> Bool

Check if an Int is a power of two.

fft3d :: Repr r Complex => Mode -> Array r DIM3 Complex -> Array U DIM3 Complex

Compute the DFT of a 3d array. Array dimensions must be powers of two else error.

fft2d :: Repr r Complex => Mode -> Array r DIM2 Complex -> Array U DIM2 Complex

Compute the DFT of a matrix. Array dimensions must be powers of two else error.

fft1d :: Repr r Complex => Mode -> Array r DIM1 Complex -> Array U DIM1 Complex

Compute the DFT of a vector. Array dimensions must be powers of two else error.