PyTorch学习问题记录

Posted 2020-09-30 Joyce_song94

Q1：def train() 中的model.train()的作用是什么？为什么要写？

A1：class torch.nn.Module中 train(mode=True)

　　Sets the module in training mode. This has any effect only on modules such as Dropout or BatchNorm.

　　参看 http://pytorch.org/docs/master/nn.html

 

Q2：torch.gather() 和 torch.norm() 函数的功能是什么？

 1 t = torch.Tensor([[1, 2], [3, 4]])
 2 print(t)
 3 a = torch.gather(t, 1, torch.LongTensor([[0,0], [1,0]]))
 4 print(a)
 5 ‘‘‘
 6  1  2
 7  3  4
 8 [torch.FloatTensor of size 2x2]
 9 
10  1  1
11  4  3
12 [torch.FloatTensor of size 2x2]
13 ‘‘‘

和

 1 a = torch.FloatTensor([[1, 2], [3, 4]])
 2 b = torch.norm(a)
 3 print(a)
 4 print(b)
 5 ‘‘‘
 6  1  2
 7  3  4
 8 [torch.FloatTensor of size 2x2]
 9 
10 5.477225575051661
11 ‘‘‘