python傅里叶逆变换_Python傅里叶逆变换

问题

我试图从一组从音频文件中获取的数据中删除一个频率。在

为了简化我的问题，我创建了下面的代码，它创建了一组wave并将它们合并到一个复杂的wave中。然后求出复波的傅里叶变换并求逆。在

我希望看到原始波形的结果，因为应该没有数据丢失，但是我收到了一个非常不同的波形。在

代码：import numpy as np

import matplotlib.pyplot as plt

import random

#Get plots

fig, c1 = plt.subplots()

c2 = c1.twinx()

fs = 100 # sample rate

f_list = [5,10,15,20,100] # the frequency of the signal

x = np.arange(fs) # the points on the x axis for plotting

# compute the value (amplitude) of the sin wave for each sample

wave = []

for f in f_list:

wave.append(list(np.sin(2*np.pi*f * (x/fs))))

#Adds the sine waves together into a single complex wave

wave4 = []

for i in range(len(wave[0])):

data = 0

for ii in range(len(wave)):

data += wave[ii][i]

wave4.append(data)

#Get frequencies from complex wave

fft = np.fft.rfft(wave4)

fft = np.abs(fft)

#Note: Here I will add some code to remove specific frequencies

#Get complex wave from frequencies

waveV2 = np.fft.irfft(fft)

#Plot the complex waves, should be the same

c1.plot(wave4, color="orange")

c1.plot(waveV2)

plt.show()

结果：(橙色为产生波，蓝色为原始波)

预期结果：

蓝色和橙色线条(原始和新创建的波浪)的值应该完全相同