FourierSeries`
FourierSeries`
NInverseDTFourierTransform
NInverseDTFourierTransform[expr,ω,n]
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 ω with period 1.
更多信息和选项
- To use NInverseDTFourierTransform, 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 nω,{ω,-π,π}]. - 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 NInverseDTFourierTransform is 
NIntegrate[expr bnω,{ω,-
,
}]. - The parameter b in the setting FourierParameters->{a,b} must be numeric.
- In addition to the option FourierParameters, NInverseDTFourierTransform can also accept the options available to NIntegrate. These options are passed directly to NIntegrate.