To draw an average line for a plot in matplotlib, we can take the following steps −
Set the figure size and adjust the padding between and around the subplots.
Make x and y data points using numpy.
Use subplots() method to create a figure and a set of subplots.
Use plot() method for x and y data points.
Find the average value of the array, x.
Plot x and y_avg data points using plot() method.
Place a legend on the figure.
To display the figure, use show() method.
Example
import numpy as np from matplotlib import pyplot as plt plt.rcParams["figure.figsize"] = [7.50, 3.50] plt.rcParams["figure.autolayout"] = True x = np.array([3, 4, 5, 6, 7, 8, 9]) y = np.array([6, 5, 4, 3, 2, 1, 6]) fig, ax = plt.subplots() ax.plot(x, y, 'o-', label='line plot') y_avg = [np.mean(x)] * len(x) ax.plot(x, y_avg, color='red', lw=6, ls='--', label="average plot") plt.legend(loc=0) plt.show()