I have quite a basic question but I could not find a similar question answered elsewhere.

I would like to add two tensors within a larger tensor. Specifically, I have a tensor of shape` (batch, seq_len, max_len, embedding_dim)`

and I want to add all of the tensors in `max_len`

so that I am left with ` (batch, seq_len, embedding_dim)`

, e.g. my new tensor’s `embedding_dim`

is all of the `max_len`

embedding dims added together.

I couldn’t find a straightforward way to do this without using a python for loop to create a new tensor which is the sum of the n tensors of `max_len`

. Also, `a.sum(-1)`

is not what I need as it just adds up all of the numbers along the row-dim. Instead (based on the below example), I would like each tensor to be :

```
[ 2.3677, 1.0233, 0.6200, -1.1026, -0.1339] + [-0.2428, 0.0120, -0.6363, 0.8928, -0.6387]
[-0.4187, 1.4169, -0.1631, 0.5966, -0.2203] + [-0.6647, 0.9166, -1.8717, -2.5794, -1.1827]
```

and so on.

Any help would be appreciated, thanks!

```
batch=2
seq_len=3
max_len=2 # max_len is the max number of components in the batch for this feature
embedding_dim=5
a = torch.randn(batch, seq_len, max_len, embedding_dim)
print(a.size())
print(a)
torch.Size([2, 3, 2, 5])
tensor([[[[ 2.3677, 1.0233, 0.6200, -1.1026, -0.1339],
[-0.2428, 0.0120, -0.6363, 0.8928, -0.6387]],
[[-0.4187, 1.4169, -0.1631, 0.5966, -0.2203],
[-0.6647, 0.9166, -1.8717, -2.5794, -1.1827]],
[[ 1.7884, -0.6862, -0.8162, -0.5604, 0.0198],
[ 0.6459, 0.3187, 1.9847, 2.4008, 0.3162]]],
[[[ 0.7555, 2.9180, 0.7002, 2.8533, -1.9177],
[-0.0804, 0.4459, 0.4908, 1.3397, -1.8577]],
[[ 0.2427, -2.0033, -0.6455, 0.0856, -0.4497],
[-0.4160, 1.3193, -0.0158, 0.1067, 0.8288]],
[[-3.3968, 0.5313, 0.4720, 0.8234, -0.3139],
[ 0.6371, -1.4486, -1.5495, -1.0803, 0.2780]]]])
```