cross_val_score在Windows10，错误与并行计算

Question

，当我试图用cross_val_score与n_job不等于1

我的系统，我遇到了一个错误是Intel的i7处理器，Windows10，python3.6 ，Spyder。

下面是我的代码：

from numpy.random import randn 
import pandas as pd 
from keras.wrappers.scikit_learn import KerasClassifier 
from sklearn.model_selection import cross_val_score 
from keras.models import Sequential 
from keras.layers import Dense 

# build a data set 
dataset = pd.DataFrame(randn(100, 2), columns='X1 X2'.split()) 
dataset["Y"]=dataset["X1"]+dataset["X2"] 

# seperate X and y 
X = dataset.iloc[:, 0:2].values 
Y = dataset.iloc[:, 2].values 

# define classifier 
def build_classifier(): 
    classifier = Sequential() 
    classifier.add(Dense(units = 2, kernel_initializer = 'uniform', activation = 'relu', input_dim = 2)) 
    classifier.add(Dense(units = 1, kernel_initializer = 'uniform', activation = 'sigmoid')) 
    classifier.compile(optimizer = 'adam', loss = 'binary_crossentropy', metrics = ['accuracy']) 
    return classifier 
classifier = KerasClassifier(build_fn = build_classifier, batch_size = 1, epochs = 4) 

class testnjob(): 
    def run(): 
     accuracies = cross_val_score(estimator = classifier, X = X, y = Y, cv = 5, n_jobs = -1) 
     return(accuracies) 
if __name__ == '__main__': 
    accuracies = testnjob.run() 

错误消息是：

ImportError: [joblib] Attempting to do parallel computing without protecting 
your import on a system that does not support forking. To use parallel- 
computing in a script, you must protect your main loop using 
"if __name__ == '__main__'". Please see the joblib documentation on Parallel 
for more information 

的代码工作，如果我设置n_jobs = 1。

有没有办法解决这个问题？

补充：代码适用于Linux虚拟机。我尝试在Virtualbox，anaconda（python 3.6）+ spyder（Tensorflow后端）上使用Ubuntu。

补充：我试过在pycharm相同的代码，不同的错误消息出现了：

AttributeError: Can't get attribute 'build_classifier' on 
<module '__main__' (built-in)> 

谢谢！

Answer 1

你可以试试这个，因为你使用的Spyder它应该很好地工作：

代码

import... 

Class Test(object): 
    def __init__(self): 
     accuracies = cross_val_score(estimator = classifier, X = X_train, y = y_train, cv = 10, n_jobs = -1) 
     ###code here 
     ###code here  

if __name__ == '__main__': 
    Test() 

希望这有助于。

与Spyder的和n_jobs类似的问题，我的帖子在这里link

编辑

解决我修改你的代码的最后一部分，它在Windows 8.1中运行良好。

另外，我使用：Theano后端。

变更部分：

from numpy.random import randn 
... 
... 
classifier = KerasClassifier(build_fn = build_classifier, batch_size = 1, epochs = 4) 

#################################################################### 
#changed part from here 

class run(): 
    def __init__(self): 
     cross_val_score(estimator = classifier, X = X, y = Y, cv = 5, n_jobs = -1) 


if __name__ == '__main__': 
    run() 

截图：