我是PyTorch的新手,并且不了解如何使用此框架适应网络。
我在Keras有一个简单的模型:
model = Sequential()
model.add(Embedding(vocab_size, embedding_size, input_length=55, weights=[pretrained_weights]))
model.add(Bidirectional(LSTM(units=len(X_train))))
model.add(Dense(n_classes, activation='softmax'))
model.compile(loss='categorical_crossentropy',
optimizer = RMSprop(lr=0.0005),
metrics=['accuracy'])
model.fit(np.array(X_train), np.array(y_train), epochs=100, validation_data=(np.array(X_val), np.array(y_val)))
在Keras中,我可以使用我的X_train(包含索引的2D数组)和我的y_train(包含每个输入的单个索引的2D数组)来提供网络。
现在,为了提供我的PyTorch模型,我将矩阵转换为这样的张量:
M = torch.tensor(X_train)
并定义了我的网络:
# Bidirectional recurrent neural network (many-to-one)
class BiRNN(nn.Module):
def __init__(self, input_size, hidden_size, num_layers, num_classes):
super(BiRNN, self).__init__()
self.hidden_size = hidden_size
self.num_layers = num_layers
self.lstm = nn.LSTM(input_size, hidden_size, num_layers, batch_first=True, bidirectional=True)
self.fc = nn.Linear(hidden_size*2, num_classes) # 2 for bidirection
def forward(self, x):
# Set initial states
h0 = torch.zeros(self.num_layers*2, x.size(0), self.hidden_size).to(device) # 2 for bidirection
c0 = torch.zeros(self.num_layers*2, x.size(0), self.hidden_size).to(device)
# Forward propagate LSTM
out, _ = self.lstm(x, (h0, c0)) # out: tensor of shape (batch_size, seq_length, hidden_size*2)
# Decode the hidden state of the last time step
out = self.fc(out[:, -1, :])
return out
model = BiRNN(input_size, hidden_size, num_layers, num_classes).to(device)
# Loss and optimizer
criterion = nn.CrossEntropyLoss()
optimizer = torch.optim.Adam(model.parameters(), lr=learning_rate)
但我不明白的是如何调用该函数并使用我自己的数据进行预测。