matplotlib.pyplot: add horizontal line to sub-plot [duplicate]

Question

This code (matplotlib.pyplot) gives me the plot in the link below:

plt.subplot(2, 1, 1)
plt.plot(px,py)

plt.subplot(2, 1, 2)
plt.plot(curve)

2 plots example --> I want to add a horizontal line in the second sub-plot at 100.000. How can I do that? The colors of both plots shall stay the same/synchronized.

Answer 1

You can use matplotlib.axes.Axes.axhline of matplotlib which adds a horizontal line across the axis. If you need to set any further parameters, refer to the official documentation

import matplotlib.pyplot as plt    
plt.axhline(100000, color="gray")