twinx and twiny in Matplotlib

1. matplotlib.axes.Axes.twinx() in Matplotlib Python
2. matplotlib.axes.Axes.twiny() in Matplotlib Python
3. Matplotlib Use twinx() and twiny() Together

This tutorial explains how we can create twin axes in Matplotlib with common X-axis or Y-axis using matplotlib.axes.Axes.twinx() and matplotlib.axes.Axes.twiny() in Python.

matplotlib.axes.Axes.twinx() in Matplotlib Python

The function matplotlib.axes.Axes.twinx() creates other axes in a Matplotlib figure sharing the common X-axis with initial axes.

import matplotlib.pyplot as plt 

students=["Anil","Sohit","Hrishav","Ayush","Sunil"]
heights_in_cms=[165,160,140,150,130]

fig,axes=plt.subplots()
fig.set_size_inches(8, 6)
axes.bar(students,heights_in_cms)
y1, y2 = axes.get_ylim() 
axes.set_xlabel("Students",fontsize=12)
axes.set_ylabel("Height in cms",fontsize=12)

twin_axes=axes.twinx() 
twin_axes.set_ylim(y1*0.394,y2*0.394)
twin_axes.set_ylabel("Height in Inches",fontsize=12)

fig.suptitle("Plot using matplotlib.axes.Axes.twinx()",fontsize=15)
plt.show()

Output:

It creates a bar plot of the height of students. The Y-axis labels at left represent the height of students in cm while the Y-axis labels at right represent students’ height in inches.

In this case, we create a new axis, twin_axes, sharing the X-axis with the axes. The Y-axis of axes has its label set to Height in cms while the Y-axis of twin_axes is set to Height in Inches.

matplotlib.axes.Axes.twiny() in Matplotlib Python

The function matplotlib.axes.Axes.twiny() creates other axes in a Matplotlib figure sharing the common Y-axis with initial axes.

import matplotlib.pyplot as plt 

distance_in_kms=[10,20,30,40,50]
fare_in_dollars=[2,3.5,5,7,10]

fig,axes=plt.subplots()
fig.set_size_inches(10, 8)
axes.plot(distance_in_kms,fare_in_dollars)
x1, x2 = axes.get_xlim() 
axes.set_xlabel("Distance in kms",fontsize=12)
axes.set_ylabel("Fare ($)",fontsize=12)

twin_axes=axes.twiny() 
twin_axes.set_xlim(x1*0.62,x2*0.62)
twin_axes.set_xlabel("Distance in miles",fontsize=12)

fig.suptitle("Plot using matplotlib.axes.Axes.twiny()",fontsize=15)
plt.show()

Output:

We create a new axis, twin_axes, sharing the Y-axis with the axes. The X-axis of axes has its label set to Distance in kms while the X-axis of twin_axes is set to Distance in miles.

Matplotlib Use twinx() and twiny() Together

import matplotlib.pyplot as plt 

distance_in_kms=[10,20,30,40,50]
fare_in_dollars=[2,3.5,5,7,10]

fig,axes=plt.subplots()
fig.set_size_inches(10, 8)
axes.plot(distance_in_kms,fare_in_dollars)
x1, x2 = axes.get_xlim() 
y1, y2 = axes.get_ylim() 
axes.set_xlabel("Distance in kms",fontsize=12)
axes.set_ylabel("Fare ($)",fontsize=12)

twin_axes=axes.twinx().twiny()

twin_axes.set_ylim(y1*0.85,y2*0.85)
twin_axes.set_ylabel("Fare in Euros",fontsize=12)

twin_axes.set_xlim(x1*0.62,x2*0.62)
twin_axes.set_xlabel("Distance in miles",fontsize=12)

fig.suptitle("Matplotlib use twinx() and twiny() together",fontsize=15)
plt.show()

Output:

It creates a Matplotlib figure with tick marks on all sides of the figure. The axes will control the left X-axis and bottom Y-axis, while the twin_axes will control the right X-axis and top Y-axis.