PR summary

Currently, due to floating-point precision, GridSpec has the quirk that the returned bottom and right might not exactly match the parameter-specified bottom and right.

For example, for a single subplot and default parameters, the axes bottom should be 0.11 and the axes top should 0.88, but the axes bottom ends up being off by one floating-point tick:

>>> import matplotlib.pyplot as plt
>>> fig, ax = plt.subplots()
>>> ax.get_position()
Bbox([[0.125, 0.10999999999999999], [0.9, 0.88]])

That's because 0.88 - (0.88 - 0.11) gets computed as 0.10999999999999999 and not 0.11.

This PR forces the GridSpec-returned bottom and right to be the parameter-specified bottom and right:

>>> import matplotlib.pyplot as plt
>>> fig, ax = plt.subplots()
>>> ax.get_position()
Bbox([[0.125, 0.11], [0.9, 0.88]])

AI Disclosure

No AI was used

PR checklist

• [N/A] "closes #0000" is in the body of the PR description to link the related issue
• new and changed code is tested
• [N/A] Plotting related features are demonstrated in an example
• [N/A] New Features and API Changes are noted with a directive and release note
• [N/A] Documentation complies with general and docstring guidelines