在keras中绘制学习曲线会给出KeyError:'val_acc' [英] Plotting learning curve in keras gives KeyError: 'val_acc'

问题描述

我试图在keras中绘制训练和测试学习曲线，但是，以下代码生成了KeyError: 'val_acc error.

I was trying to plot train and test learning curve in keras, however, the following code produces KeyError: 'val_acc error.

官方文档<https://keras.io/callbacks/>指出，要使用'val_acc'，我需要启用我不了解并且不知道如何在我的代码中使用的验证和准确性监视.

The official document <https://keras.io/callbacks/> states that in order to use 'val_acc' I need to enable validation and accuracy monitoring which I dont understand and dont know how to use in my code.

任何帮助将不胜感激. 谢谢.

Any help would be much appreciated. Thanks.

seed = 7
np.random.seed(seed)

dataframe = pandas.read_csv("iris.csv", header=None)
dataset = dataframe.values
X = dataset[:,0:4].astype(float)
Y = dataset[:,4]

encoder = LabelEncoder()
encoder.fit(Y)
encoded_Y = encoder.transform(Y)
dummy_y = np_utils.to_categorical(encoded_Y)

kfold = StratifiedKFold(y=Y, n_folds=10, shuffle=True, random_state=seed)
cvscores = []

for i, (train, test) in enumerate(kfold):

    model = Sequential()
    model.add(Dense(12, input_dim=4, init='uniform', activation='relu'))
    model.add(Dense(3, init='uniform', activation='sigmoid'))
    model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])
    history=model.fit(X[train], dummy_y[train], nb_epoch=200, batch_size=5, verbose=0)
    scores = model.evaluate(X[test], dummy_y[test], verbose=0)
    print("%s: %.2f%%" % (model.metrics_names[1], scores[1]*100))
    cvscores.append(scores[1] * 100)

print( "%.2f%% (+/- %.2f%%)" % (np.mean(cvscores), np.std(cvscores))) 


print(history.history.keys())
# summarize history for accuracy
plt.plot(history.history['acc'])
plt.plot(history.history['val_acc'])
plt.title('model accuracy')
plt.ylabel('accuracy')
plt.xlabel('epoch')
plt.legend(['train', 'test'], loc='upper left')
plt.show()

推荐答案

在Keras + Tensorflow 2.0中的外观val_acc已重命名为val_accuracy

Looks like in Keras + Tensorflow 2.0 val_acc was renamed to val_accuracy

这篇关于在keras中绘制学习曲线会给出KeyError:'val_acc'的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！