尝试在3D matplotlib中绘制多元函数返回空数字

Question

我试图在3D matplotlib中绘制函数F(x1,x2)，遵循这里的教程:http://glowingpython.blogspot.com/2012/01/how-to-plot-two-variable-functions-with.html

一旦我尝试运行代码，结果显示图形是空的，甚至没有看到轴输出。我想知道是否有人能找出这种行为背后的原因。我正在使用python 2.7

from __future__ import division
from numpy import exp,arange
from pylab import meshgrid,cm,imshow,contour,clabel,colorbar,axis,title,show
import math 
from mpl_toolkits.mplot3d import Axes3D
from matplotlib import cm
from matplotlib.ticker import LinearLocator, FormatStrFormatter
import matplotlib.pyplot as plt
from matplotlib import pylab
from numpy import arange,array,ones
from scipy import stats
import numpy
import matplotlib.ticker as mtick
import sys
import os

# the function that I'm going to plot
def z_func(x1,x2):
 return exp(-(1-x1)**2 - 100*((x2-x1**2)**2))

x1 = arange(5.0,-5.0,-0.01)
x2 = arange(-5.0,5.0,0.01)
X1,X2 = meshgrid(x1, x2) # grid of point
Z = z_func(X1, X2) # evaluation of the function on the grid

fig = plt.figure()
ax = fig.gca(projection='3d')
surf = ax.plot_surface(X1, X2, Z, rstride=1, cstride=1, cmap=cm.RdBu,linewidth=0, antialiased=False)
ax.zaxis.set_major_locator(LinearLocator(10))
ax.zaxis.set_major_formatter(FormatStrFormatter('%.02f'))
ax.set_xlabel('x-axis')
ax.set_ylabel('y-axis')
ax.set_zlabel('z-axis')
ax.view_init(elev=25, azim=-120)
fig.colorbar(surf, shrink=0.5, aspect=5)
plt.show()

Answer 1

你的代码为我工作。我只需要等待计算机完成计算。计算时间长是因为x1和x2的大小。试着修改这些行:

x1 = arange(5.0,-5.0,-0.01)
x2 = arange(-5.0,5.0,0.01)

到以下行:

x1 = arange(5.0,-5.0,-0.1)
x2 = arange(-5.0,5.0,0.1)

注。我建议你安排一下进口。您只需要以下内容:

from numpy import exp, arange
import matplotlib.pyplot as plt
from matplotlib.ticker import LinearLocator, FormatStrFormatter
from pylab import meshgrid
from mpl_toolkits.mplot3d import Axes3D
from matplotlib import cm