Python spyder + tensorflow 交叉验证在 Windows 10 上冻结

Posted 2023-03-29

【中文标题】Python spyder + tensorflow 交叉验证在 Windows 10 上冻结

【英文标题】：Python spyder + tensorflow cross validation freezes on Windows 10

【发布时间】：2018-11-05 21:36:11

【问题描述】：

在 Windows 10 上，我安装了Anaconda 并启动了Spyder。我还成功安装了Theano、Tensorflow和Keras，因为当我执行时

导入 keras

控制台输出

使用 TensorFlow 后端

当我编译并拟合神经网络时，它运行良好。但是当我尝试运行 k 折交叉验证，通过 keras 包装器结合 scikit-learn 并使用参数 n_jobs = -1 （通常 n_jobs 具有任何值，因此具有多处理）时，控制台会永远冻结，直到重新启动内核手动或终止 Spyder。

另一个问题，当我尝试使用 GridSearchCV 运行一些参数调整时，即 100 个 epoch，它不会冻结，但它输出 epoch 1/1 而不是 1/100，通常它会给出不好的结果，而不是逻辑（即它只运行几分钟，而通常需要几个小时！）。

我的代码是：

# Part 1 - Data Preprocessing

# Importing the libraries
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd

# Importing the dataset
dataset = pd.read_csv('Churn_Modelling.csv')
X = dataset.iloc[:, 3:13].values
y = dataset.iloc[:, 13].values

# Encoding categorical data
# Encoding the Independent Variable
from sklearn.preprocessing import LabelEncoder, OneHotEncoder
labelencoder_X_1 = LabelEncoder()
X[:, 1] = labelencoder_X_1.fit_transform(X[:, 1])
labelencoder_X_2 = LabelEncoder()
X[:, 2] = labelencoder_X_2.fit_transform(X[:, 2])
onehotencoder = OneHotEncoder(categorical_features = [1])
X = onehotencoder.fit_transform(X).toarray()

# Avoiding the dummy variable trap
X = X[:, 1:]

# Splitting the dataset into the Training set and Test set
from sklearn.cross_validation import train_test_split
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size = 0.2, random_state = 0)

# Feature Scaling
from sklearn.preprocessing import StandardScaler
sc = StandardScaler()
X_train = sc.fit_transform(X_train)
X_test = sc.transform(X_test)

# Part 2 - Now let's make the ANN!

# Importing the Keras libraries and packages
import keras
from keras.models import Sequential
from keras.layers import Dense
from keras.layers import Dropout
# Initialising the ANN
classifier = Sequential()

# Adding the input layer and the first hidden layer with dropout
classifier.add(Dense(units = 6, kernel_initializer = 'uniform', activation = 'relu', input_dim = 11))
classifier.add(Dropout(rate = 0.1))    # p should vary from 0.1 to 0.4, NOT HIGHER, because then we will have under-fitting.

# Adding the second hidden layer with dropout
classifier.add(Dense(units = 6, kernel_initializer = 'uniform', activation = 'relu'))
classifier.add(Dropout(rate = 0.1))

# Adding the output layer
classifier.add(Dense(units = 1, kernel_initializer = 'uniform', activation = 'sigmoid'))

# Compiling the ANN
classifier.compile(optimizer = 'adam', loss = 'binary_crossentropy', metrics = ['accuracy'])

# Fitting the ANN to the Training set
classifier.fit(X_train, y_train, batch_size = 10, epochs = 100)

# Part 3 - Making predictions and evaluating the model

# Predicting the Test set results
y_pred = classifier.predict(X_test)
y_pred = (y_pred > 0.5)

# Making the Confusion Matrix
from sklearn.metrics import confusion_matrix
cm = confusion_matrix(y_test, y_pred)

new_prediction = classifier.predict(sc.transform(np.array([[0, 0, 600, 1, 40, 3, 60000, 2, 1, 1, 50000]])))
new_prediction = (new_prediction > 0.5)

#Part 4 = Evaluating, Improving and Tuning the ANN

# Evaluating the ANN
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
def build_classifier():
    classifier = Sequential()
    classifier.add(Dense(units = 6, kernel_initializer = 'uniform', activation = 'relu', input_dim = 11))
    classifier.add(Dense(units = 6, kernel_initializer = 'uniform', activation = 'relu'))
    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 = 10, nb_epoch = 100)
accuracies = cross_val_score(estimator = classifier, X = X_train, y = y_train, cv = 10, n_jobs = -1)
mean = accuracies.mean()
variance = accuracies.std()

# Improving the ANN

# Tuning the ANN
from keras.wrappers.scikit_learn import KerasClassifier
from sklearn.model_selection import GridSearchCV
from keras.models import Sequential
from keras.layers import Dense
def build_classifier(optimizer):
    classifier = Sequential()
    classifier.add(Dense(units = 6, kernel_initializer = 'uniform', activation = 'relu', input_dim = 11))
    classifier.add(Dense(units = 6, kernel_initializer = 'uniform', activation = 'relu'))
    classifier.add(Dense(units = 1, kernel_initializer = 'uniform', activation = 'sigmoid'))
    classifier.compile(optimizer = optimizer, loss = 'binary_crossentropy', metrics = ['accuracy'])
    return classifier
classifier = KerasClassifier(build_fn = build_classifier)
parameters = "batch_size": [25, 32],
              "nb_epoch": [100, 500],
              "optimizer": ["adam", "rmsprop"]
grid_search = GridSearchCV(estimator = classifier,
                           param_grid = parameters,
                           scoring = "accuracy",
                           cv = 10)
grid_search = grid_search.fit(X_train, y_train)
best_parameters = grid_search.best_params_
best_accuracy = grid_search.best_score_

此外，对于 n_jobs = 1，它运行但说 epoch 1/1 并运行 10 次，这是 k-fold 值。这意味着它识别 nb_epoch = 1 而不是 100 出于某种原因。 最后，我尝试将 cross_val_score() 封装到一个类中：

class run():
    def __init__(self):
            cross_val_score(estimator = classifier, X = X_train, y = y_train, cv = 10, n_jobs = -1)

if __name__ == '__main__':
    run()

或仅在 if 条件下使用：

if __name__ == '__main__':
   cross_val_score(estimator = classifier, X = X_train, y = y_train, cv = 10, n_jobs = -1)

但它也不起作用，它再次冻结。

谁能帮我解决这些问题？发生了什么事，我能做些什么来解决这些问题，以便一切正常运行？ 提前谢谢你。

【参考方案1】：

似乎 Windows 的“n_jobs”有问题，在你的“accuracies=”代码中删除它，它会起作用，缺点是它可能需要一段时间，但至少它会起作用。