How do I align gridlines for two y-axis scales using Matplotlib?

Question

I'm plotting two datasets with different units on the y-axis. Is there a way to make the ticks and gridlines aligned on both y-axes?

The first image shows what I get, and the second image shows what I would like to get.

This is the code I'm using to plot:

import seaborn as sns import numpy as np import pandas as pd  np.random.seed(0) fig = plt.figure() ax1 = fig.add_subplot(111) ax1.plot(pd.Series(np.random.uniform(0, 1, size=10))) ax2 = ax1.twinx() ax2.plot(pd.Series(np.random.uniform(10, 20, size=10)), color='r') 

Answer 1

I am not sure if this is the prettiest way to do it, but it does fix it with one line:

import matplotlib.pyplot as plt import seaborn as sns import numpy as np import pandas as pd  np.random.seed(0) fig = plt.figure() ax1 = fig.add_subplot(111) ax1.plot(pd.Series(np.random.uniform(0, 1, size=10))) ax2 = ax1.twinx() ax2.plot(pd.Series(np.random.uniform(10, 20, size=10)), color='r')  # ADD THIS LINE ax2.set_yticks(np.linspace(ax2.get_yticks()[0], ax2.get_yticks()[-1], len(ax1.get_yticks())))  plt.show() 

Answer 2

I could solve it by deactivating ax.grid(None) in one of the grid`s axes:

import matplotlib.pyplot as plt import seaborn as sns import numpy as np import pandas as pd  fig = plt.figure() ax1 = fig.add_subplot(111) ax1.plot(pd.Series(np.random.uniform(0, 1, size=10))) ax2 = ax1.twinx() ax2.plot(pd.Series(np.random.uniform(10, 20, size=10)), color='r') ax2.grid(None)  plt.show()