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NInverseDTFourierTransform


gives a numerical approximation to the inverse discrete time Fourier transform of expr evaluated at the integer n, where expr is a periodic function of with period 1.
  • The numerical approximation to the inverse discrete time Fourier transform of expr is by default defined to be NIntegrate[expr n , {, -, }].
  • Different choices for the definition of the inverse discrete time Fourier transform can be specified using the option FourierParameters.
  • With the setting FourierParameters, expr is assumed to have a period of , and the inverse discrete time Fourier transform computed by is NIntegrate[expr b n , {, -, }].
Numerical value for a sequence with a given discrete time Fourier transform:
Compare with the answer from symbolic evaluation:
Needs["FourierSeries`"]
Numerical value for a sequence with a given discrete time Fourier transform:
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Compare with the answer from symbolic evaluation:
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