Matplotlib Subplot Arrangement Using HBoxDivider and VBoxDivider

Introduction

In this lab, we will learn how to use Matplotlib to create subplots using the HBoxDivider and VBoxDivider classes. We will use a simple example to show how these classes can be used to arrange multiple subplots.

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Skills Graph

Import Required Libraries

We begin by importing the required libraries - matplotlib and numpy.

import matplotlib.pyplot as plt
import numpy as np

Create Data

We create two numpy arrays to be used as the data for our subplots.

arr1 = np.arange(20).reshape((4, 5))
arr2 = np.arange(20).reshape((5, 4))

Create Subplots Using HBoxDivider

We create two subplots side-by-side using the HBoxDivider class. We also adjust the axes' location so that they have equal heights while maintaining their aspect ratios.

fig, (ax1, ax2) = plt.subplots(1, 2)
ax1.imshow(arr1)
ax2.imshow(arr2)

pad = 0.5  ## pad in inches
divider = HBoxDivider(
    fig, 111,
    horizontal=[Size.AxesX(ax1), Size.Fixed(pad), Size.AxesX(ax2)],
    vertical=[Size.AxesY(ax1), Size.Scaled(1), Size.AxesY(ax2)])
ax1.set_axes_locator(divider.new_locator(0))
ax2.set_axes_locator(divider.new_locator(2))

plt.show()

Create Subplots Using VBoxDivider

We create two subplots one below the other using the VBoxDivider class. We adjust the axes' location so that they have equal widths while maintaining their aspect ratios.

fig, (ax1, ax2) = plt.subplots(2, 1)
ax1.imshow(arr1)
ax2.imshow(arr2)

divider = VBoxDivider(
    fig, 111,
    horizontal=[Size.AxesX(ax1), Size.Scaled(1), Size.AxesX(ax2)],
    vertical=[Size.AxesY(ax1), Size.Fixed(pad), Size.AxesY(ax2)])

ax1.set_axes_locator(divider.new_locator(0))
ax2.set_axes_locator(divider.new_locator(2))

plt.show()

Summary

In this lab, we learned how to use the HBoxDivider and VBoxDivider classes in Matplotlib to create subplots. We saw how to adjust the axes' location so that they have equal heights or widths while maintaining their aspect ratios. These classes can be useful when we need to arrange multiple subplots in a single figure.