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NDTFourierTransform

NDTFourierTransform[expr, n, Omega]
gives a numerical approximation to the discrete time Fourier transform of expr evaluated at the numerical value Omega, where expr is a function of n.
  • The numerical approximation to the discrete time Fourier transform of expr is by default defined to be NSum[expr ExponentialE-ImaginaryI n Omega, {n, -Infinity, Infinity}].
  • Different choices for the definition of the discrete time Fourier transform can be specified using the option FourierParameters.
  • With the setting FourierParameters->{a, b}, the discrete time Fourier transform computed by NDTFourierTransform is .
  • In addition to the option FourierParameters, NDTFourierTransform can also accept the options available to NSum. These options are passed directly to NSum.
Needs["FourierSeries`"]
Different definitions for numerical approximation of a discrete time Fourier transform:
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Compare with the answer from symbolic evaluation with FourierSequenceTransform:
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