torch.nn.functional.unfold
torch.nn.functional.unfold(input, kernel_size, dilation=1, padding=0, stride=1)
Extracts sliding local blocks from a batched input tensor.
Warning:
 Currently, only 4-D input tensors (batched image-like tensors)
 are supported.

Warning:
 More than one element of the unfolded tensor may refer to a
 single memory location. As a result, in-place operations
 (especially ones that are vectorized) may result in incorrect
 behavior. If you need to write to the tensor, please clone it
 first.

See "torch.nn.Unfold" for details
Return type:
      Tensor