<p>我相信matplotlib还没有在3D中正确设置等轴。。。但我在几天前发现了一个我已经适应了的技巧(我不记得在哪里)。其概念是在数据周围创建一个伪立方体边界框。
您可以使用以下代码对其进行测试:</p>
<pre><code>from mpl_toolkits.mplot3d import Axes3D
from matplotlib import cm
import matplotlib.pyplot as plt
import numpy as np
fig = plt.figure()
ax = fig.gca(projection='3d')
ax.set_aspect('equal')
X = np.random.rand(100)*10+5
Y = np.random.rand(100)*5+2.5
Z = np.random.rand(100)*50+25
scat = ax.scatter(X, Y, Z)
# Create cubic bounding box to simulate equal aspect ratio
max_range = np.array([X.max()-X.min(), Y.max()-Y.min(), Z.max()-Z.min()]).max()
Xb = 0.5*max_range*np.mgrid[-1:2:2,-1:2:2,-1:2:2][0].flatten() + 0.5*(X.max()+X.min())
Yb = 0.5*max_range*np.mgrid[-1:2:2,-1:2:2,-1:2:2][1].flatten() + 0.5*(Y.max()+Y.min())
Zb = 0.5*max_range*np.mgrid[-1:2:2,-1:2:2,-1:2:2][2].flatten() + 0.5*(Z.max()+Z.min())
# Comment or uncomment following both lines to test the fake bounding box:
for xb, yb, zb in zip(Xb, Yb, Zb):
ax.plot([xb], [yb], [zb], 'w')
plt.grid()
plt.show()
</code></pre>
<p>z数据的数量级大约大于x和y,但即使使用等轴选项,matplotlib也会自动缩放z轴:</p>
<p><img src="https://i.stack.imgur.com/thEFk.png" alt="bad"/></p>
<p>但是,如果添加边界框,则可以获得正确的缩放比例:</p>
<p><img src="https://i.stack.imgur.com/2PxuW.png" alt="enter image description here"/></p>