我正在研究临床EHR。我目前指的是这个blog和github链接here。我已经生成了数据集并按照存储库中存在的笔记本中的说明对其进行了处理。我在尝试训练模型时遇到问题。
build_EHRNN类。
torch.manual_seed(1)
class build_EHRNN(nn.Module):
def __init__(self, inputDimSize=4894, hiddenDimSize=[200,200], batchSize=100, embSize=200, numClass=4894, dropout=0.5, logEps=1e-8):
super(build_EHRNN, self).__init__()
self.inputDimSize = inputDimSize
self.hiddenDimSize = hiddenDimSize
self.numClass = numClass
self.embSize = embSize
self.batchSize = batchSize
self.dropout = nn.Dropout(p=0.5)
self.logEps = logEps
# Embedding inputs
self.W_emb = nn.Parameter(torch.randn(self.inputDimSize, self.embSize).cuda())
self.b_emb = nn.Parameter(torch.zeros(self.embSize).cuda())
self.W_out = nn.Parameter(torch.randn(self.hiddenDimSize, self.numClass).cuda())
self.b_out = nn.Parameter(torch.zeros(self.numClass).cuda())
self.params = [self.W_emb, self.W_out,
self.b_emb, self.b_out]
def forward(self,x, y, h, lengths, mask):
self.emb = torch.tanh(torch.matmul(x, self.W_emb) + self.b_emb)
input_values = self.emb
self.outputs = [input_values]
for i, hiddenSize in enumerate([self.hiddenDimSize, self.hiddenDimSize]): # iterate over layers
rnn = EHRNN(self.inputDimSize,hiddenSize,self.embSize,self.batchSize,self.numClass) # calculate hidden states
hidden_state = []
h = self.init_hidden().cuda()
for i,seq in enumerate(input_values): # loop over sequences in each batch
h = rnn(seq, h)
hidden_state.append(h)
hidden_state = self.dropout(torch.stack(hidden_state)) # apply dropout between layers
input_values = hidden_state
y_linear = torch.matmul(hidden_state, self.W_out) + self.b_out # fully connected layer
yhat = F.softmax(y_linear, dim=1) # yhat
yhat = yhat*mask[:,:,None] # apply mask
# Loss calculation
cross_entropy = -(y * torch.log(yhat + self.logEps) + (1. - y) * torch.log(1. - yhat + self.logEps))
last_step = -torch.mean(y[-1] * torch.log(yhat[-1] + self.logEps) + (1. - y[-1]) * torch.log(1. - yhat[-1] + self.logEps))
prediction_loss = torch.sum(torch.sum(cross_entropy, dim=0),dim=1)/ torch.cuda.FloatTensor(lengths)
cost = torch.mean(prediction_loss) + 0.000001 * (self.W_out ** 2).sum() # regularize
return (yhat, hidden_state, cost)
def init_hidden(self):
return torch.zeros(self.batchSize, self.hiddenDimSize) # initial state
创建实例和训练模型
model = build_EHRNN(inputDimSize=4894, hiddenDimSize=200, batchSize=100, embSize=200, numClass=4894, dropout=0.5, logEps=1e-8)
model = model.to(device)
optimizer = torch.optim.Adadelta(model.parameters(), lr = 0.01, rho=0.90)
max_epochs = 10
loss_all = []
iteration = 0
for e in range(max_epochs):
for index in random.sample(range(n_batches), n_batches):
batchX = train[0][:n_batches*batchSize][index*batchSize:(index+1)*batchSize]
batchY = train[1][:n_batches*batchSize][index*batchSize:(index+1)*batchSize]
optimizer.zero_grad()
x, y, lengths, mask = padding(batchX, batchY, 4894, 4894)
if torch.cuda.is_available():
x, y, lenghts, mask = x.cuda(), y.cuda(), lengths, mask.cuda()
outputs, hidden, cost = model(x,y, h, lengths, mask)
if torch.cuda.is_available():
cost.cuda()
cost.backward()
nn.utils.clip_grad_norm_(model.parameters(), 5)
optimizer.step()
错误：
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
<ipython-input-14-cff1f002dced> in <module>()
17 x, y, lenghts, mask = x.cuda(), y.cuda(), lengths, mask.cuda()
18
---> 19 outputs, hidden, cost = model(x,y, h, lengths, mask)
20
21 if torch.cuda.is_available():
NameError: name 'h' is not defined
更新： 删除“ h”参数会产生以下错误
---------------------------------------------------------------------------
RuntimeError Traceback (most recent call last)
<ipython-input-14-6495250d91c9> in <module>()
18
19 # outputs, hidden, cost = model(x,y, h, lengths, mask)
---> 20 outputs, hidden, cost = model(x, y, lengths, mask)
21
22 if torch.cuda.is_available():
1 frames
/usr/local/lib/python3.6/dist-packages/torch/nn/modules/module.py in _call_impl(self, *input, **kwargs)
720 result = self._slow_forward(*input, **kwargs)
721 else:
--> 722 result = self.forward(*input, **kwargs)
723 for hook in itertools.chain(
724 _global_forward_hooks.values(),
<ipython-input-7-3c831fe3ca8d> in forward(self, x, y, lengths, mask)
36 h = rnn(seq, h)
37 hidden_state.append(h)
---> 38 hidden_state = self.dropout(torch.stack(hidden_state)) # apply dropout between layers
39 input_values = hidden_state
40
RuntimeError: stack expects a non-empty TensorList
答案 0 :(得分：0)
我想我已解决您的错误：
将您的前进方法替换为：
def forward(self,x, y, lengths, mask):
self.emb = torch.tanh(torch.matmul(x, self.W_emb) + self.b_emb)
input_values = self.emb
self.outputs = [input_values]
for i, hiddenSize in enumerate([self.hiddenDimSize, self.hiddenDimSize]): # iterate over layers
rnn = EHRNN(self.inputDimSize,hiddenSize,self.embSize,self.batchSize,self.numClass) # calculate hidden states
hidden_state = []
h = self.init_hidden().cuda()
for i,seq in enumerate(input_values): # loop over sequences in each batch
h = rnn(seq, h)
hidden_state.append(h)
hidden_state = self.dropout(torch.stack(hidden_state)) # apply dropout between layers
input_values = hidden_state
y_linear = torch.matmul(hidden_state, self.W_out) + self.b_out # fully connected layer
yhat = F.softmax(y_linear, dim=1) # yhat
yhat = yhat*mask[:,:,None] # apply mask
并替换发生错误的行：
outputs, hidden, cost = model(x, y, lengths, mask)