pytorch中tensor.expand()和tensor.expand_as()函数详解

>>> import torch
>>> a=torch.tensor([[2],[3],[4]])
>>> print(a.size())
torch.Size([3, 1])
>>> a.expand(3,2)
tensor([[2, 2],
    [3, 3],
    [4, 4]])
>>> a
tensor([[2],
    [3],
    [4]])

>>> b=torch.tensor([[2,2],[3,3],[5,5]])
>>> print(b.size())
torch.Size([3, 2])
>>> a.expand_as(b)
tensor([[2, 2],
    [3, 3],
    [4, 4]])
>>> a
tensor([[2],
    [3],
    [4]])