Tom Xue - 10 months ago 21

Python Question

I find below code from a book to show how to use matplotlib in Python. The code runs normally. But I don't understand what does the symbol $ or $\ mean here?

`# -*- coding: utf-8 -*-`

import numpy as np

import matplotlib.pyplot as plt

x = np.linspace(0, 10, 1000)

y = np.sin(x) + 1

z = np.cos(x**2) + 1

plt.figure(figsize = (8, 4))

plt.plot(x,y,label = '$\sin x+1$', color = 'red', linewidth = 2)

plt.plot(x, z, 'b--', label = '$\cos x^2+1$')

plt.xlabel('Time(s) ')

plt.ylabel('Volt')

plt.title('A Simple Example')

plt.ylim(0, 2.2)

plt.legend()

plt.show()

Answer

It doesn't mean anything in Python. `$`

marks the beginning and end of maths in a LaTeX string.

`$\sin x+1$`

means

Similarly, `$\cos x^2+1$`

will be

For a basic tutorial in MathJax (which uses LaTeX syntax) read this.