Mastering Matplotlib 2.x

Adding horizontal and vertical lines

We will begin by importing our required libraries, as shown:

import numpy as npimport matplotlib as mplimport matplotlib.pyplot as plt%matplotlib inline# Set up figure size and DPI for screen demoplt.rcParams['figure.figsize'] = (6,4)plt.rcParams['figure.dpi'] = 150

1. We will create the simple sine plot that we saw in Chapter 1, Heavy Customization, as follows:

# Adding a horizontal and vertical linenums = np.arange(0,10,0.1)plt.plot(nums, np.sin(nums))

We will get the following output:

2. Now, to add an annotation, say, a line that splits the region between stuff above and below 0.5, add a horizontal line ...