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.

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  • To use , you first need to load the Fourier Series Package using Needs["FourierSeries`"].
  • 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->{a, b}, expr is assumed to have a period of , and the inverse discrete time Fourier transform computed by is NIntegrate[expr bn, {, -, }].
  • The parameter b in the setting FourierParameters->{a, b} must be numeric.
  • In addition to the option FourierParameters, can also accept the options available to NIntegrate. These options are passed directly to NIntegrate.

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基本范例 (1)基本范例 (1)

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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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