matplotlib 图形的乳胶渲染文本的中心标题

Question

I would like to center a title for a Matplotlib figure which includes a newline return (\\) when rendering it LaTeX style

inserting a simple return code for latex \\\\ in the middle of the title will work, but will not have it centered so that the newline is awkwardly shifted from the first line.

from matplotlib import pyplot as plt
plt.rc('text', usetex=True)
plt.title(r"\center{\textbf{Some title \\ with with a newline}}")

or

plt.title(r"\begin{centering}{\textbf{Some title \\ with a newline}\end{centering}")

won't work

When I input the previously cited lines, I get no title output at all on the figure. I do not have a LaTeX error on the python command interpreter though.

Answer 1

You can easily use \\n to get newline within plt.title() :

import numpy as np
import matplotlib.pyplot as plt

plt.rc('text', usetex=True)

t = np.arange(0., 5., 0.2)

plt.plot(t, t/5000,)
plt.title(r"$\textbf{Some title}$"
          "\n"
          r"$\textbf{with a formula}:$"
          "\n"
          r"$y=t/5000$")
plt.show()

Answer 2

Assuming you have a proper LaTex installed on your system, and all set up to use LaTex from within matplotlib, you have to set a specific LaTex preamble in which /begin{center} ... /end{center} is available.

Here is a working example.

import numpy as np
import matplotlib
matplotlib.rcParams['text.usetex'] = True
import matplotlib.pyplot as plt

custom_preamble = {                                                                          
    "text.latex.preamble":                                                                   
        r"\usepackage{amsmath}" # for the align, center,... environment
        ,
    }   
plt.rcParams.update(custom_preamble)                                                         
plt.figure(figsize= (6,4),tight_layout = True)                                               

t = np.linspace(0.0, 1.0, 100)
s = np.cos(4 * np.pi * t) + 2
plt.plot(t, s,label='your legend')

plt.xlabel(r'\textbf{bold (s)}')                                                        
plt.ylabel('\\textit{italic (\N{DEGREE SIGN}/sec)}', fontsize=16)                   
plt.title(r'\begin{center}Your title\\ new line, centered: ($-e^{i\pi}$, centered\end{center}')                  
plt.legend()
plt.show()

This gives: