matplotlib（2）-- 坐标轴的相关操作

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(-3, 3, 50)
y1 = 2 * x + 1

#figure 1
plt.figure()
plt.plot(x, y1)

#横纵坐标轴显示范围设置
plt.xlim((-1, 2))
plt.ylim((-2, 3))

#横纵坐标轴名称设置
plt.xlabel("I am X")
plt.ylabel("I am Y")

#横纵坐标轴重新定义
new_ticks = np.linspace(-1, 2, 5)     #Return evenly spaced numbers over a specified interval.
plt.xticks(new_ticks)
plt.yticks([-2, -1.8, -1, 1.22, 3,],
           [r'$really\ bad$', r'$bad$', r'$normal$', r'$good$', r'$really\ good$',])
plt.show()

 #坐标轴的移动

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(-3, 3, 50)
y1 = 2 * x + 1

#figure 1
plt.figure()
plt.plot(x, y1)

#横纵坐标轴显示范围设置
plt.xlim((-1, 2))
plt.ylim((-2, 3))

#坐标轴的移动 gca = “get current axis”
ax = plt.gca()
ax.spines["right"].set_color("none")
ax.spines["top"].set_color("none")
ax.xaxis.set_ticks_position("bottom")
ax.yaxis.set_ticks_position("left")
ax.spines["bottom"].set_position(("data", 0))   #Set the X and Y coordinates of the sprite simultaneously
ax.spines["left"].set_position(("data", 0))

plt.show()