In this

CodePudding user response：

The lines are attributes of the PartialDependenceDisplay returned by plot_partial_dependence. The attributes are called deciles_vlines_ (for vertical lines) and deciles_hlines_ for horizontal lines. If you don't want to show them you can set them to not be visible with e.g. plt.setp

import matplotlib.pyplot as plt
disp = plot_partial_dependence(...)
plt.setp(disp.deciles_vlines_, visible=False)