pytorch tensor常用函数

a = Variable(torch.Tensor([1, 2, 3]))
print(a.size(0))
``

```python
if output.data.is_cuda:
	output.data = output.data.cpu()

keypoints = []
for sample_data in test_data_batches:
    keypoints.append(output.numpy())
keypoints = np.concatenate(keypoints, axis=0)