Python数据分析三大框架之matplotlib（六）axis, ticks坐标轴设置

axis，ticks为图像的坐标的设置，有以下为其中几种设置的方法。

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(-3, 3, 50)
y1 = 2*x + 1
y2 = x**2

plt.figure()
plt.plot(x, y2)
plt.plot(x, y1, color='red', linewidth= 1.0, linestyle='--')

# set axis 坐标
plt.xlim((-1, 2)) # x轴的范围
plt.ylim((-2, 3)) # y轴的范围
plt.xlabel('I am x') # x轴的标签
plt.ylabel('I am y') # y轴的标签


# ticks 方法来设置坐标轴
new_ticks = np.linspace(-1, 2, 5)
print(new_ticks)
plt.xticks(new_ticks)

plt.yticks([-2,-1.8, -1, 1.22, 3], ['$really\ good$', '$bad$', '$normal$', '$good$', '$really\ good$'])

# 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))
ax.spines['left'].set_position(('data', 0))


plt.show()