NDTFourierTransform


gives a numerical approximation to the discrete time Fourier transform of expr evaluated at the numerical value , where expr is a function of n.

更多信息更多信息

  • To use , you first need to load the Fourier Series Package using Needs["FourierSeries`"].
  • The numerical approximation to the discrete time Fourier transform of expr is by default defined to be NSum[expr -n, {n, -∞, ∞}].
  • 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 is NSum[expr -bn, {n, -∞, ∞}].
  • 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 NSum. These options are passed directly to NSum.

范例范例打开所有单元关闭所有单元

基本范例 (1)基本范例 (1)

In[1]:=
Click for copyable input

Different definitions for numerical approximation of a discrete time Fourier transform:

In[2]:=
Click for copyable input
Out[2]=
In[3]:=
Click for copyable input
Out[3]=

Compare with the answer from symbolic evaluation with FourierSequenceTransform:

In[4]:=
Click for copyable input
Out[4]=
In[5]:=
Click for copyable input
Out[5]=
In[6]:=
Click for copyable input
Out[6]=
New to Mathematica? Find your learning path »
Have a question? Ask support »