# tensorplay.functional.vstack

Source: https://www.tensorplay.cn/docs/generated/tensorplay.functional.vstack.html

```python
tensorplay.functional.vstack(tensors, *, out=None) → Tensor
```

Stack tensors in sequence vertically (row wise).

This is equivalent to concatenation along the first axis after all 1-D tensors have been reshaped by tensorplay.atleast_2d().

Parameters:

tensors (sequence of Tensors) – sequence of tensors to concatenate

Keyword Arguments:

out ([Tensor](/docs/generated/tensorplay.Tensor.html#tensorplay.Tensor), optional) – the output tensor.

Example:

```
>>> a = tensorplay.tensor([1, 2, 3])
>>> b = tensorplay.tensor([4, 5, 6])
>>> tensorplay.vstack((a,b))
tensor([[1, 2, 3],
        [4, 5, 6]])
>>> a = tensorplay.tensor([[1],[2],[3]])
>>> b = tensorplay.tensor([[4],[5],[6]])
>>> tensorplay.vstack((a,b))
tensor([[1],
        [2],
        [3],
        [4],
        [5],
        [6]])
```