BSS_Synthesis of ECG Signals_ZX.py

# -*- coding: utf-8 -*-
"""
2018/10/31
Electrocardiogram Signal Generator

"""

import numpy as np
import matplotlib.pyplot as plt

t = np.linspace(-1.5,1.5,20000)
e_a = np.zeros(t.size)
e_b = np.zeros(t.size)
pk = np.array([8, 12.434, 10.775, 9.121, 8.77, 10.053, 12.066, 13.924, 15.069, 15.143, 14.021, 11.911, 9.361, 7.112, 5.732, 5.121, 4.701, 4.115, 3.3, 2.283, 1.129, 0.555, 1.489, 2.25, 2.54, 2.349, 1.815, 1.15, 0.549, 0.25, 0.494])
Ok = np.array([0, 0.912, 1.769, 2.513, 3.165, 3.902, 4.8, 5.799, 0.553, 1.593, 2.610, 3.585, 4.489, 5.295, 6.029, 0.531, 1.459, 2.519, 3.670, 4.886, 6.261, 2.713, 4.555, 5.745, 0.545, 1.579, 2.582, 3.573, 4.660, 0.302, 1.979])

# (a)ten harmonics
for k in np.arange(1,11) :  # k = 1,2,...,10
    e_a = e_a + pk[k]*np.cos(2*np.pi*k*1.2*t + Ok[k])

plt.figure(figsize=(15,5))
plt.subplot(1, 2, 1)
plt.plot(t, e_a)
plt.xlim(-1.5,1.5)
plt.xlabel("t") 
plt.ylabel("e10(t)") 
plt.title("ten harmonics") 

# (b) DC term and 30 harmonics
for k in range(31) :  # k = 0,1,2,...,30
    e_b = e_b + pk[k]*np.cos(2*np.pi*k*1.2*t + Ok[k])

plt.subplot(1, 2, 2)
plt.plot(t, e_b)
plt.xlim(-1.5,1.5)
plt.xlabel("t") 
plt.ylabel("e30(t)") 
plt.title("DC term and 30 harmonics") 

# save the figure
plt.savefig(fname = "HW2.png", format = "png")