Question

离散傅立叶逆变换已知频域函数,并取得离散值,需要做傅立叶逆变换,转换为离散的时域值.现在已知转换后时域下的时间轴长度为0

Answer 1

Mathematica中的离散傅立叶变换:

Here is some sample data.

In[1]:=data = {1.3, 2.4, 1.7, 4.1, 2.9, 1.7, 5.1, 2.7};

This computes the discrete Fourier transform of the data. In general, the result is a list of complex numbers.

In[2]:=Fourier[data]

Out[2]={7.74282[InvisibleSpace] + 0. [ImaginaryI], -0.740685 -

0.677082 [ImaginaryI], -0.919239 - 0.954594 [ImaginaryI], -0.390685 +

1.72708 [ImaginaryI],

0.0353553[InvisibleSpace] + 0. [ImaginaryI], -0.390685 -

1.72708 [ImaginaryI], -0.919239 + 0.954594 [ImaginaryI], -0.740685 +

0.677082 [ImaginaryI]}

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