DFT matrix

In applied mathematics, a DFT matrix is an expression of a discrete Fourier transform (DFT) as a transformation matrix, which can be applied to a signal through matrix multiplication.

An N-point DFT is expressed as the multiplication ${\displaystyle X=Wx}$, where ${\displaystyle x}$ is the original input signal, ${\displaystyle W}$ is the N-by-N square DFT matrix, and ${\displaystyle X}$ is the DFT of the signal.

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