Pthon Matplotlib 画图

 1 import matplotlib.pyplot as plt
 2 import numpy as np
 3 
 4 # 绘制普通图像
 5 x = np.linspace(-1, 1, 50)
 6 y1 = 2 * x + 1
 7 y2 = x**2
 8 
 9 plt.figure()
10 # 在绘制时设置lable, 逗号是必须的
11 l1, = plt.plot(x, y1, label = ‘line‘)
12 l2, = plt.plot(x, y2, label = ‘parabola‘, color = ‘red‘, linewidth = 1.0, linestyle = ‘--‘)
13 
14 # 设置坐标轴的取值范围
15 plt.xlim((-1, 1))
16 plt.ylim((0, 2))
17 
18 # 设置坐标轴的lable
19 plt.xlabel(‘X axis‘)
20 plt.ylabel(‘Y axis‘)
21 
22 # 设置x坐标轴刻度, 原来为0.25, 修改后为0.5
23 plt.xticks(np.linspace(-1, 1, 5))
24 # 设置y坐标轴刻度及标签, $$是设置字体
25 plt.yticks([0, 0.5], [‘$minimum$‘, ‘normal‘])
26 
27 # 设置legend
28 plt.legend(handles = [l1, l2,], labels = [‘a‘, ‘b‘], loc = ‘best‘)
29 plt.show()