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I have an matlab example of this program but I can't do it in Python. How it must look like (mathlab example) https://imgur.com/a/oam3jXl.

import numpy as np
import matplotlib.pyplot as plt
from scipy.signal import hilbert, chirp
duration = int(input("Input duration of signal = "))
A = int(input("Input amplitude of signal = "))
start = int(input("Input start of modulation time = "))
end = int(input("Input lenght of modulation = "))
fs = 400.0
samples = int(fs*duration)
t = np.arange(samples) / fs
main_t = []
result = []
counter=0
for l in range(0,samples):
    main_t.append(0)
    result.append(0)
start_mod = np.arange(start*fs)
end_mod = np.arange(end*fs)
signal = chirp(t, 20.0, t[-1], 100.0)
signal *= (A + 0.5 * np.sin(2.0*np.pi*3.0*t) )

for i in np.arange(0,start*fs):
    signal.insert(i,0)

fig = plt.figure()
ax0 = fig.add_subplot(211)
ax0.plot(main_t, result)
ax0.set_xlabel("time in seconds")
plt.show()

I expect the inputing some data from console and then print graph using matplotlib for example. Graph must look like graph that u can see on image(mathlab example).

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1 回答 1

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忽略获取输入的所有摆弄（根据其他约束条件会有很大差异），生成幅度调制信号的代码应该很简单。

我首先引入 numpy，生成一组对信号进行采样的点，计算幅度，然后将它们组合起来：

import numpy as np

x = np.linspace(0, 10, 501)
ampl = np.exp(-(x - 3.5)**2 / 0.8)
y = np.sin(x * 25) * ampl

然后我们可以使用 matplotlib 绘制这些，例如：

import matplotlib.pyplot as plt

plt.figure(figsize=(10,5))
plt.plot(x, y, label='signal')
plt.plot(x, ampl, ':', label='amplitude')
plt.xlabel('time')
plt.ylabel('value')
plt.legend()

演示图

我已经加入了 seaborn，并且正在使用他们的ticks风格让它更漂亮一些。

于 2019-06-26T13:52:39.207 回答