pytorch将model放置到GPU(cuda)上，运行时报错Expected all tensors to be on the same device, but found at least tw

完整报错：Expected all tensors to be on the same device, but found at least two devices, cuda:0 and cpu! (when checking argument for argument index in method wrapper__index_select)

环境：python3,游戏本（带gpu）

1. 将model放置到cuda上：

USE_CUDA = torch.cuda.is_available() 
if USE_CUDA:
   model = model.cuda()

2.单步调试找到报错的代码：

 x = self.embedding(x) 
#---------------------------------------

loss = Loss(out,y)

3. 解决：在执行以上报错代码前将变量放置到cuda上：

x=x.to(device=torch.device('cuda' if USE_CUDA else 'cpu'))
#---------------------------------------------------------
out=out.to(device=torch.device('cuda' if USE_CUDA else 'cpu'))
y=y.to(device=torch.device('cuda' if USE_CUDA else 'cpu'))

4. 成功运行，无报错