Changing Matplotlib subplot size/position after axes creation

In Matplotlib, you can change the size and position of subplots even after axes creation using GridSpec and position methods. This is useful when you need to dynamically adjust subplot layouts.

Steps to Change Subplot Size/Position

• Create a figure using figure() method
• Add an axes to the figure using add_subplot()
• Create a GridSpec layout for positioning subplots
• Set the position using set_position()
• Update the subplot specification with set_subplotspec()
• Add additional subplots if needed
• Use tight_layout() to adjust spacing

Example

Here's how to resize and reposition a subplot after creation ?

import matplotlib.pyplot as plt
import matplotlib.gridspec as gridspec

# Set figure size
plt.rcParams["figure.figsize"] = [7.00, 3.50]
plt.rcParams["figure.autolayout"] = True

# Create figure and initial subplot
fig = plt.figure()
ax = fig.add_subplot(111)
ax.plot([1, 2, 3, 4], [1, 4, 2, 3], 'bo-', label='Original')

# Create GridSpec layout
gs = gridspec.GridSpec(3, 1)

# Change subplot position and size
ax.set_position(gs[0:2].get_position(fig))
ax.set_subplotspec(gs[0:2])

# Add another subplot
ax2 = fig.add_subplot(gs[2])
ax2.plot([1, 2, 3, 4], [3, 1, 4, 2], 'r^-', label='New subplot')

fig.tight_layout()
plt.show()

Understanding GridSpec Parameters

The GridSpec(3, 1) creates a 3×1 grid layout ?

import matplotlib.pyplot as plt
import matplotlib.gridspec as gridspec

fig = plt.figure(figsize=(8, 6))

# Create 2x2 grid
gs = gridspec.GridSpec(2, 2, hspace=0.3, wspace=0.2)

# Different positioning options
ax1 = fig.add_subplot(gs[0, :])  # Top row, all columns
ax2 = fig.add_subplot(gs[1, 0])  # Bottom left
ax3 = fig.add_subplot(gs[1, 1])  # Bottom right

ax1.plot([1, 2, 3], [1, 4, 2])
ax1.set_title('Spans entire top row')

ax2.plot([1, 2, 3], [2, 1, 3])
ax2.set_title('Bottom left')

ax3.plot([1, 2, 3], [3, 2, 1])
ax3.set_title('Bottom right')

plt.show()

Key Methods

Conclusion

Use GridSpec with set_position() and set_subplotspec() to dynamically change subplot layouts. This approach provides flexible control over subplot arrangement after axes creation.