3.7节报错问题

[liyuxuanzzz]

报错是这一句
d2l.train_ch3(net, train_iter, test_iter, loss, num_epochs, batch_size, None, None, optimizer)
报错如下：
RuntimeError: Tensor for 'out' is on CPU, Tensor for argument #1 'self' is on CPU, but expected them to be on GPU (while checking arguments for addmm)
在源代码末尾加上.cuda（）依旧报错，求解