Search code examples
pythonmatplotlibsubplotfigure

How do I change the figure size with subplots?


How do I increase the figure size for this figure?

This does nothing:

f.figsize(15, 15)

Example code from the link:

import matplotlib.pyplot as plt
import numpy as np

# Simple data to display in various forms
x = np.linspace(0, 2 * np.pi, 400)
y = np.sin(x ** 2)

plt.close('all')

# Just a figure and one subplot
f, ax = plt.subplots()
ax.plot(x, y)
ax.set_title('Simple plot')

# Two subplots, the axes array is 1-d
f, axarr = plt.subplots(2, sharex=True)
axarr[0].plot(x, y)
axarr[0].set_title('Sharing X axis')
axarr[1].scatter(x, y)

# Two subplots, unpack the axes array immediately
f, (ax1, ax2) = plt.subplots(1, 2, sharey=True)
ax1.plot(x, y)
ax1.set_title('Sharing Y axis')
ax2.scatter(x, y)

# Three subplots sharing both x/y axes
f, (ax1, ax2, ax3) = plt.subplots(3, sharex=True, sharey=True)
ax1.plot(x, y)
ax1.set_title('Sharing both axes')
ax2.scatter(x, y)
ax3.scatter(x, 2 * y ** 2 - 1, color='r')
# Fine-tune figure; make subplots close to each other and hide x ticks for
# all but bottom plot.
f.subplots_adjust(hspace=0)
plt.setp([a.get_xticklabels() for a in f.axes[:-1]], visible=False)

# row and column sharing
f, ((ax1, ax2), (ax3, ax4)) = plt.subplots(2, 2, sharex='col', sharey='row')
ax1.plot(x, y)
ax1.set_title('Sharing x per column, y per row')
ax2.scatter(x, y)
ax3.scatter(x, 2 * y ** 2 - 1, color='r')
ax4.plot(x, 2 * y ** 2 - 1, color='r')

# Four axes, returned as a 2-d array
f, axarr = plt.subplots(2, 2)
axarr[0, 0].plot(x, y)
axarr[0, 0].set_title('Axis [0,0]')
axarr[0, 1].scatter(x, y)
axarr[0, 1].set_title('Axis [0,1]')
axarr[1, 0].plot(x, y ** 2)
axarr[1, 0].set_title('Axis [1,0]')
axarr[1, 1].scatter(x, y ** 2)
axarr[1, 1].set_title('Axis [1,1]')
# Fine-tune figure; hide x ticks for top plots and y ticks for right plots
plt.setp([a.get_xticklabels() for a in axarr[0, :]], visible=False)
plt.setp([a.get_yticklabels() for a in axarr[:, 1]], visible=False)

# Four polar axes
f, axarr = plt.subplots(2, 2, subplot_kw=dict(projection='polar'))
axarr[0, 0].plot(x, y)
axarr[0, 0].set_title('Axis [0,0]')
axarr[0, 1].scatter(x, y)
axarr[0, 1].set_title('Axis [0,1]')
axarr[1, 0].plot(x, y ** 2)
axarr[1, 0].set_title('Axis [1,0]')
axarr[1, 1].scatter(x, y ** 2)
axarr[1, 1].set_title('Axis [1,1]')
# Fine-tune figure; make subplots farther from each other.
f.subplots_adjust(hspace=0.3)

plt.show()

Solution

  • Use .set_figwidth and .set_figheight on the matplotlib.figure.Figure object returned by plt.subplots(), or set both with f.set_size_inches(w, h).

    f.set_figheight(15)
    f.set_figwidth(15)
    

    Note: Unlike set_size_inches(), where the measurement unit is explicitly mentioned in the function's name, this is not the case for set_figwidth() and set_figheight(), which also use inches. This information is provided by the documentation of the function.

    Alternatively, when using .subplots() to create a new figure, specify figsize=:

    f, axs = plt.subplots(2, 2, figsize=(15, 15))
    

    .subplots accepts **fig_kw, which are passed to pyplot.figure, and is where figsize can be found.

    Setting the figure's size may trigger the ValueError exception:

    Image size of 240000x180000 pixels is too large. It must be less than 2^16 in each direction
    

    This is a common problem for using the set_fig*() functions due to the assumptions that they work with pixels and not inches (obviously 240000*180000 inches is too much).