How to plot a simple vertical line on a matplotlib figure ?

Examples of how to plot a simple vertical line on a matplotlib figure

Plot a simple vertical line

To plot a simple vertical line on a matplotlib figure, a solution is to use axvline, example

import matplotlib.pyplot as plt
import numpy as np

x = np.linspace(0, 2*np.pi, 1000)
y1 = np.sin(x)

f = plt.figure()

ax = f.add_subplot(111)

plt.plot(x, y1, '-b', label='sine')

plt.axvline(x=np.pi,color='red')

plt.title('Matplotlib Vertical Line')

plt.xlim(0, 2.0*np.pi)
plt.ylim(-1.5, 1.5)

plt.savefig('matplotlib_vertical_line.png', bbox_inches='tight')
plt.show()

Change the color

plt.axvline(x=np.pi,color='gray')

Dashed line

plt.axvline(x=np.pi,color='gray',linestyle='--')

References