[pytorch] El índice de dimensión del tensor, la diferencia entre a[:,:,1] y a[:,1]

a=torch.rand(4,3,2)
b=a[:,:,1]
c=a[:,1]  

print(a)
tensor([[[0.5200, 0.9955],
         [0.3993, 0.1790],
         [0.4560, 0.8735]],
        [[0.6110, 0.7368],
         [0.4449, 0.4358],
         [0.0840, 0.5496]],
        [[0.4827, 0.4580],
         [0.1750, 0.7478],
         [0.3505, 0.0089]],
        [[0.4543, 0.4423],
         [0.2201, 0.3439],
         [0.0718, 0.4791]]])
print(b.size())
torch.Size([4, 3])
print(b)
tensor([[0.9955, 0.1790, 0.8735],
        [0.7368, 0.4358, 0.5496],
        [0.4580, 0.7478, 0.0089],
        [0.4423, 0.3439, 0.4791]])
print(c.size())
torch.Size([4, 2])
print(c)
tensor([[0.3993, 0.1790],
        [0.4449, 0.4358],
        [0.1750, 0.7478],
        [0.2201, 0.3439]])
d=[:,1,:] # 这个例子中，其实a[:,1]=a[:,1,:],即c=d
print(d) 
tensor([[0.3993, 0.1790],
        [0.4449, 0.4358],
        [0.1750, 0.7478],
        [0.2201, 0.3439]])