The mathematical formula

One . Preface

When visualizing , We often encounter the situation of drawing some formulas , These formulas appear in the legend 、 Axis labels and titles , The problem is that if you use ordinary strings to write formulas, the display effect is very poor , The comparison is as follows ：

You can see that the legend on the left is irregular and unsightly , But with the LaTeX The formula shows that the effect has been greatly improved .

Two . Solution

Matplotlib Internal LaTeX Parser and layout engine . So you can use it directly LaTeX Write the formula .

Draw two functions as an example ：

• ${\sum }_1^{n}x+3$
• $\sin x\cos x$

The complete procedure is as follows ：

import matplotlib.pyplot as plt

import numpy as np

plt.rcParams['font.sans-serif'] = ['SimHei']  #  Settings support Chinese 
plt.rcParams['axes.unicode_minus'] = False  #  Set up - Number 

#  obtain X and Y
n = 15
x_1 = np.arange(1, n+1, 1)
y_1 = np.cumsum(x_1) + 3

x_2 = np.arange(0, 2*np.pi, np.pi/36)
y_2 = np.sin(x_2) * np.cos(x_2)

figure, ax = plt.subplots(1, 2)
#  mapping 
ax[0].plot(x_1, y_1, lw=3, color='k', label='$\sum_{1}^{n}x+3}$')
ax[0].set_title('$\sum_{1}^{n}x+3}$ function ', fontsize=20)
ax[0].set_xlabel("X", fontsize=15)
ax[0].set_ylabel('$\sum_{1}^{n}x+3}$ function ', fontsize=15)
ax[0].legend()

ax[1].plot(x_2, y_2, lw=3, color='r', label='$\sin x \cos x$')
ax[1].set_title('$\sin x \cos x$ function ', fontsize=20)
ax[1].set_xlabel("X", fontsize=15)
ax[1].set_ylabel('$\sin x \cos x$ function ', fontsize=15)
ax[1].legend()

plt.show()

2.1 The legend uses a mathematical formula

2.2 The title uses mathematical formulas

2.3 Axis labels use mathematical formulas

3、 ... and . Reference resources

1. Solution to the problem of cylinder annotation
2. linestyle Parameters,
3. capstyle Parameters,
4. joinstyle Parameters,
5. Solution to subgraph spacing problem
6. Subgraph setting headline solution
7. Drawing scale setting solution