`adjustable` keyword argument for setting equal aspect ratios in 3D

While setting equal aspect ratios for 3D plots, users can choose to modify

either the data limits or the bounding box.

.. plot::

:include-source: true

import matplotlib.pyplot as plt

import numpy as np

from itertools import combinations, product

aspects = ('auto', 'equal', 'equalxy', 'equalyz', 'equalxz')

fig, axs = plt.subplots(1, len(aspects), subplot_kw={'projection': '3d'},

figsize=(12, 6))

# Draw rectangular cuboid with side lengths [4, 3, 5]

r = [0, 1]

scale = np.array([4, 3, 5])

pts = combinations(np.array(list(product(r, r, r))), 2)

for start, end in pts:

if np.sum(np.abs(start - end)) == r[1] - r[0]:

for ax in axs:

ax.plot3D(*zip(start*scale, end*scale), color='C0')

# Set the aspect ratios

for i, ax in enumerate(axs):

ax.set_aspect(aspects[i], adjustable='box')

ax.set_title(f"set_aspect('{aspects[i]}')")

plt.show()