我的网络架构如下:
model = Sequential()model.add(Embedding(9761, 100, input_length=longest_period))model.add(LSTM(30, dropout=0.2, recurrent_dropout=0.2))model.add(Dense(1, activation='sigmoid'))model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])
当我尝试训练模型时:
res = model.fit(X_train_lsmt, np.array(y_train_lsmt), validation_split=0.25, epochs=2, batch_size=128, verbose=0)
我得到了以下错误:
ValueError: Error when checking model input: expectedembedding_3_input to have shape (None, 217) but got array with shape (3133, 1)
我认为这个错误可能是由于y_train_lsmt
的一热编码,形状为(3133,3)
[[ 0. 1. 0.] [ 0. 1. 0.] [ 0. 0. 1.] ..., [ 1. 0. 0.] [ 1. 0. 0.] [ 0. 1. 0.]]
但我对此并不确定。
更新:
我通过添加Flatten()
层部分解决了这个问题:
model = Sequential()model.add(Embedding(9761, 100, input_length=stringa_piu_lunga))model.add(LSTM(units=10, return_sequences=True))model.add(Flatten())model.add(Dense(3, activation='softmax'))model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])
但现在在模型评估时得到了同样的错误:
score = model.evaluate(X_test_lsmt, y_train_lsmt, verbose=0)
回答:
你的代码看起来没问题。将y_train_lstm
转换为分类数据:
y_train_lstm = keras.utils.to_categorical(y_train_lstm)
或者将损失函数改为稀疏分类交叉熵:
model.compile(optimizer='adam', loss='sparse_categorical_crossentropy', metrics=['accuracy'])
编辑:根据你的GitHub仓库,评估不会成功,因为你没有预处理x_test_lstm
。请尝试:
X_test_lstm = sequence.pad_sequences(X_test_lstm, maxlen=longest_string)