首页 > 解决方案 > 使用嵌入层序列化 keras 模型

问题描述

我已经用这样的预训练词嵌入训练了一个模型:

embedding_matrix = np.zeros((vocab_size, 100))
for word, i in text_tokenizer.word_index.items():
    embedding_vector = embeddings_index.get(word)
    if embedding_vector is not None:
        embedding_matrix[i] = embedding_vector

embedding_layer = Embedding(vocab_size,
                        100,
                        embeddings_initializer=Constant(embedding_matrix),
                        input_length=50,
                        trainable=False)

架构如下所示:

sequence_input = Input(shape=(50,), dtype='int32')
embedded_sequences = embedding_layer(sequence_input)
text_cnn = Conv1D(filters=5, kernel_size=5, padding='same',     activation='relu')(embedded_sequences)
text_lstm = LSTM(500, return_sequences=True)(embedded_sequences)


char_in = Input(shape=(50, 18, ))
char_cnn = Conv1D(filters=5, kernel_size=5, padding='same', activation='relu')(char_in)
char_cnn = GaussianNoise(0.40)(char_cnn)
char_lstm = LSTM(500, return_sequences=True)(char_in)



merged = concatenate([char_lstm, text_lstm]) 

merged_d1 = Dense(800, activation='relu')(merged)
merged_d1 = Dropout(0.5)(merged_d1)

text_class = Dense(len(y_unique), activation='softmax')(merged_d1)
model = Model([sequence_input,char_in], text_class)

当我将模型转换为 json 时,出现此错误:

ValueError: can only convert an array of size 1 to a Python scalar

同样,如果我使用该model.save()功能,它似乎可以正确保存,但是当我去加载它时,我得到Type Error: Expected Float32.

我的问题是:尝试序列化此模型时是否遗漏了什么?我需要某种Lambda层或类似的东西吗?

任何帮助将不胜感激!

标签: tensorflowkerasword-embedding

解决方案


您可以使用 layer 中的weights参数Embedding来提供初始权重。

embedding_layer = Embedding(vocab_size,
                            100,
                            weights=[embedding_matrix],
                            input_length=50,
                            trainable=False)

模型保存/加载后,权重应保持不可训练:

model.save('1.h5')
m = load_model('1.h5')
m.summary()

__________________________________________________________________________________________________
Layer (type)                    Output Shape         Param #     Connected to
==================================================================================================
input_3 (InputLayer)            (None, 50)           0
__________________________________________________________________________________________________
input_4 (InputLayer)            (None, 50, 18)       0
__________________________________________________________________________________________________
embedding_1 (Embedding)         (None, 50, 100)      1000000     input_3[0][0]
__________________________________________________________________________________________________
lstm_4 (LSTM)                   (None, 50, 500)      1038000     input_4[0][0]
__________________________________________________________________________________________________
lstm_3 (LSTM)                   (None, 50, 500)      1202000     embedding_1[0][0]
__________________________________________________________________________________________________
concatenate_2 (Concatenate)     (None, 50, 1000)     0           lstm_4[0][0]
                                                                 lstm_3[0][0]
__________________________________________________________________________________________________
dense_2 (Dense)                 (None, 50, 800)      800800      concatenate_2[0][0]
__________________________________________________________________________________________________
dropout_2 (Dropout)             (None, 50, 800)      0           dense_2[0][0]
__________________________________________________________________________________________________
dense_3 (Dense)                 (None, 50, 15)       12015       dropout_2[0][0]
==================================================================================================
Total params: 4,052,815
Trainable params: 3,052,815
Non-trainable params: 1,000,000
__________________________________________________________________________________________________

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