DMelt:DSP/1 Fast Fourier Transforms

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Fast Fourier transforms

FFT implementations

There are several packages dealing with the fast fourier transform (FFT) problem. We will discuss the fastest one, which uses many threads and the multicore computer architecture. It is based on the ParallelColt as implemented by Piotr Wendykier.

In this example we will use DComplexFactory2D factory to create a random dense matrix (DenseDComplexMatrix2D) and perform FCC.

Discrete Cosine Transform (DCT)

This example is based on the real DenseDoubleMatrix2D matrix.

You can also use 3D matrix methods, see DenseDoubleMatrix3D

Discrete Fourier transform (DFT)

This is 1D DFT transform of a complex matrix 1000x1000 using several processing cores:

More information on this topic is in DMelt books