Hi,

I know that one can use setElt to get a "sub-tensor" for a specific index value in a specific Index by the following code

```
auto i = Index(4);
auto j = Index(3);
auto T = randomITensor(i,j);
T *= setElt(i=2);
```

My question is, is there (or will it be implemented) a function to get a more general sub-tensor, for example i from 1 to 2 and j from 2 to 3?

If this task is essentially to copy the corresponding elements or to multiple zeros, I may implement it by myself, but I wonder if there is a more efficient way to do it.

Thanks!

Chia-Min