当我使用mplot3D时，为什么会出现错误：NameError：未定义名称'plot_trisurf'

Question

I try to use mplot3D to draw some 3D pictures:

import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
...
plot_trisurf(X, Y, Z1)

Then my computer will tell me that

NameError: name 'plot_trisurf' is not defined

Why this happen? I thought I have imported it already.

Answer 1

plot_trisurf is a method from the Axes3D class. In python, in order to call a class method, you usually need to provide the class or an instance of it.

In this case the class instance would be your axes object. This is usually called ax . The correct call would therefore be (as seen on the matplotlib trisurf example ):

import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

fig = plt.figure()
ax = fig.gca(projection='3d')
...
ax.plot_trisurf(x, y, z)
plt.show()