import numpy as np
import matplotlib.pyplot as mp

# 线性拆分1000个点
x = np.linspace(-np.pi, np.pi, 1000) 
sinx = np.sin(x)
# 余弦曲线 cos(x)/2
cosx = np.cos(x)/2
# 修改x轴的刻度文本
vals = [-np.pi, -np.pi/2, 0, np.pi/2, np.pi]
texts = [r'$-\pi$',r'$-\frac{\pi}{2}$','0',r'$\pi$',r'$\frac{\pi}{2}$'] #-π,-π/2,0,π/2,π#
mp.xticks(vals, texts)

mp.plot(x, sinx,linestyle="--",linewidth=2,alpha=0.5)
mp.plot(x, cosx,linestyle=":", color="green")
mp.show()

学习自：
https://www.bilibili.com/video/BV1Yo4y197bN?p=20&spm_id_from=pageDriver