Changing Matplotlib subplot size/position after axes creation

To change subplot size or position after axes creation, we can take the following steps−

Create a new figure or activate an existing figure using figure() method.
Add an '~.axes.Axes' to the figure as part of a subplot arrangement using add_subplot() method.
A grid layout to place subplots within a figure using GridSpec() class.
Set the position of the grid specs.
Set the subplotspec instance.
Add an '~.axes.Axes' to the figure as part of a subplot arrangement using add_subplot() method, with gridspec instance.
Adjust the padding between and around the subplots.
To display the figure, use show() method.

Example

from matplotlib import pyplot as plt
from matplotlib import gridspec as gridspec
plt.rcParams["figure.figsize"] = [7.00, 3.50]
plt.rcParams["figure.autolayout"] = True
fig = plt.figure()
ax = fig.add_subplot(111)
gs = gridspec.GridSpec(3, 1)
ax.set_position(gs[0:2].get_position(fig))
ax.set_subplotspec(gs[0:2])
fig.add_subplot(gs[2])
fig.tight_layout()
plt.show()