我正在尝试为 Keras 中的 XOR 问题实现一个简单的分类器。这是代码:
from keras.models import Sequential
from keras.layers.core import Dense, Dropout, Activation
from keras.optimizers import SGD
import numpy
X = numpy.array([[1., 1.], [0., 0.], [1., 0.], [0., 1.], [1., 1.], [0., 0.]])
y = numpy.array([[0.], [0.], [1.], [1.], [0.], [0.]])
model = Sequential()
model.add(Dense(2, input_dim=2, init='uniform', activation='sigmoid'))
model.add(Dense(3, init='uniform', activation='sigmoid'))
model.add(Dense(1, init='uniform', activation='softmax'))
sgd = SGD(lr=0.001, decay=1e-6, momentum=0.9, nesterov=True)
model.compile(loss='mean_squared_error', optimizer=sgd)
model.fit(X, y, nb_epoch=20)
print()
score = model.evaluate(X, y)
print()
print(score)
print(model.predict(numpy.array([[1, 0]])))
print(model.predict(numpy.array([[0, 0]])))
我尝试更改 epoch 数、学习率和其他参数。但是从第一个时期到最后一个时期,误差保持不变。
Epoch 13/20
6/6 [==============================] - 0s - loss: 0.6667
Epoch 14/20
6/6 [==============================] - 0s - loss: 0.6667
Epoch 15/20
6/6 [==============================] - 0s - loss: 0.6667
Epoch 16/20
6/6 [==============================] - 0s - loss: 0.6667
Epoch 17/20
6/6 [==============================] - 0s - loss: 0.6667
Epoch 18/20
6/6 [==============================] - 0s - loss: 0.6667
Epoch 19/20
6/6 [==============================] - 0s - loss: 0.6667
Epoch 20/20
6/6 [==============================] - 0s - loss: 0.6667
6/6 [==============================] - 0s
0.666666686535
[[ 1.]]
[[ 1.]]
你如何在 Keras 中训练这个网络?
另外,是否有更好的库来实现神经网络?我尝试了 PyBrain,但它已被放弃,尝试了 scikit-neuralnetwork 但文档真的很神秘,所以无法弄清楚如何训练它。我严重怀疑 Keras 是否有效。