Question

我已经尝试过使用meshgrid，但它不起作用，我真的找不到问题... E = np.zeros（2500）是一个数组，所以我找不到什么错误... 提前致谢

import numpy as np
import numpy.random as rd
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
from mkgrid2d import *

W1 = np.linspace(-1.0,3.0,num = 50)
W0 = np.linspace(-2.0,4.0,num = 50)

w11 = 1.00
w00=1.0

w = np.array([[w11],[w00]],dtype=float)

mew = 0
sigma = np.sqrt(2)


Npts=50;rd.seed(1)
x1=rd.rand(1,Npts)*10.-5.0 #Npts uniformemente distribuídos
r = np.random.normal(mew, sigma, 50)*2.-1.0#ruído gaussiano distribuído

X = np.vstack((x1,np.ones((1,x1.shape[1]))))
X = X.astype('float') #converter para float

N=Npts 

y = np.dot(w.T,X) + r
E= np.zeros(2500)

“E”将是轮廓的Z

count = 0
for i in range (len(W1)):
    for j in range (len (W0)):
        w1 = np.array([W1[i],W0[j]])
        yn = np.dot(w1.T,X)
        E[count] = (1./50)*(np.sum((y-yn)**2))
        count +=1

plt.figure()
CS = plt.contour(W1,W0,E)
plt.clabel(CS, inline=1, fontsize=10)
plt.title('Simplest default with labels')

Answer 1

正如错误消息所示，您需要E数组为 2D ，形状为(50,50)，而不是形状为(2500)的1D数组。< / p>

有几种解决方法：

在分配后重新塑造您的E
```
E = E.reshape(len(W1),len(W0))
```

首先使用正确的形状创建E，然后使用i和j对其进行索引

E = np.zeros((len(W1),len(W0)))

for i in range (len(W1)):
    for j in range (len (W0)):
        w1 = np.array([W1[i],W0[j]])
        yn = np.dot(w1.T,X)
        E[i][j] = (1./50)*(np.sum((y-yn)**2))

Mathplotlib轮廓错误：输入z必须是2D数组

1 个答案: