Subplots, Grids, and Layouts

Subplots and Layout Management

Often you need multiple plots in a single figure.

Simple 2×2 grid of subplots

fig, axs = plt.subplots(2, 2, figsize=(10,8))
axs[0,0].plot(x, y)
axs[0,0].set_title('Top‑Left')
axs[0,1].scatter(x, y)
axs[0,1].set_title('Top‑Right')
axs[1,0].hist(y, bins=20)
axs[1,0].set_title('Bottom‑Left')
axs[1,1].boxplot(y)
axs[1,1].set_title('Bottom‑Right')
plt.tight_layout()
plt.show()

Using GridSpec for custom layout

import matplotlib.gridspec as gridspec

fig = plt.figure(constrained_layout=True)
gs = gridspec.GridSpec(3, 3, figure=fig)
ax1 = fig.add_subplot(gs[0, :])   # first row, spanning all columns
ax2 = fig.add_subplot(gs[1:, 0:2]) # bottom‑left 2×2 block
ax3 = fig.add_subplot(gs[1:, 2])   # rightmost column, spanning rows 1‑2

Sharing axes

fig, (ax1, ax2) = plt.subplots(2, 1, sharex=True, sharey=True)

Adding a single legend for all subplots

handles, labels = ax1.get_legend_handles_labels()
fig.legend(handles, labels, loc='upper center', ncol=3)