import numpy as np
import matplotlib.pyplot as plt
import cmath
# 常量初始化
E10=0
E20=0
a=0.8
b=0.9
k=0.4
N=500
# E实部，Ey虚部
E1=np.zeros(N)
E2=np.zeros(N)

# Ex实部，Ey虚部
Ex=np.zeros(N)
Ey=np.zeros(N)

x=y1=y2=[] # 这是新加的
p=2
for i in range(N - 1):
    #先计算弧度
    hudu = k - p / (1 + Ex[i] * Ex[i] + Ey[i] * Ey[i])
    # 实部计算
    Ex[i + 1] = a + b * (Ex[i] * cmath.cos(hudu).real - Ey[i] * np.sin(hudu).real)
    # 虚部计算
    Ey[i + 1] = b * (Ex[i] * cmath.sin(hudu).real - Ey[i] * np.cos(hudu).real)
    x.append(i+1)
    y1.append(Ex[i+1].real)
    y2.append(Ey[i+1].real)
    plt.plot(x, y1, 'r', label='实部Ex曲线')
    plt.plot(x, y2, 'b', label='虚部Ey曲线')
plt.show()