F.conv1d(autograd.Variable(torch.randn(20, 1, 4 *200 )), autograd.Variable(torch.randn(256, 1, 2 * 200)), stride=200, padding=0, dilation=2).size()
i think this should get  tensor with size (20, 256, 2)
but i got tensor with size (20, 256, 1), what is the problem ?