Fourier

Fourier[list] finds the discrete Fourier transform of a list of complex numbers.

Examples

DFT of a simple signal:

Fourier[{1, 1, 1, 1, 0, 0, 0, 0}]
(* {1.41421, 0.5 + 0.5 I, 0, 0.5 - 0.5 I, 0, ...} *)

Sinusoidal signal:

data = Table[Sin[2 Pi k / 8], {k, 0, 7}];
Abs[Fourier[data]]
(* {0, 0, 1.41, 0, 0, 0, 1.41, 0} *)

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