id,node_id,number,title,user,state,locked,assignee,milestone,comments,created_at,updated_at,closed_at,author_association,active_lock_reason,draft,pull_request,body,reactions,performed_via_github_app,state_reason,repo,type
1812811751,I_kwDOAMm_X85sDU_n,8008,"""Deep linking"" disparate documentation resources together",35968931,open,0,,,3,2023-07-19T22:18:55Z,2023-10-12T18:36:52Z,,MEMBER,,,,"### What is your issue?

Our docs have a general issue with having lots of related resources that are not necessarily linked together in a useful way. This results in users (including myself!) getting ""stuck"" in one part of the docs and being unaware of material that would help them solve their specific issue.

To give a concrete example, if a user wants to know about `coarsen`, there is relevant material:

- In the [coarsen class docstring](https://docs.xarray.dev/en/stable/generated/xarray.core.rolling.DatasetCoarsen.html#xarray.core.rolling.DatasetCoarsen)
- On the [reshaping page](https://docs.xarray.dev/en/stable/user-guide/reshaping.html#reshaping-via-coarsen)
- On the [computations page](https://docs.xarray.dev/en/stable/user-guide/computation.html#coarsen-large-arrays)
- On the [""how do I?"" page](https://docs.xarray.dev/en/stable/howdoi.html)
- On the [tutorial repository](https://tutorial.xarray.dev/fundamentals/03.3_windowed.html?highlight=coarsen#coarsening)

Different types of material are great, but only some of these resources are linked to others. `Coarsen` is actually pretty well covered overall, but for other functions there might be no useful linking at all, or no examples in the docstrings.

---

The biggest missed opportunity here is the way all the great content on the [tutorial.xarray.dev](https://tutorial.xarray.dev/) repository is not linked from anywhere on the main documentation site (I believe). To address that we could either (a) integrate the `tutorial.xarray.dev` material into the main site or (b) add a lot more cross-linking between the two sites.

Identifying sections that could be linked and adding links would be a great task for new contributors.","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/8008/reactions"", ""total_count"": 2, ""+1"": 2, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue
1812188730,I_kwDOAMm_X85sA846,8004,Rotation Functional Index example,35968931,open,0,,,2,2023-07-19T15:23:20Z,2023-08-24T13:26:56Z,,MEMBER,,,,"### Is your feature request related to a problem?

I'm trying to think of an example that would demonstrate the ""functional index"" pattern discussed in https://github.com/pydata/xarray/issues/3620.

I think a 2D rotation is the simplest example of an analytically-expressible, non-trivial, domain-agnostic case where you might want to back a set of multiple coordinates with a single functional index. It's also nice because there is additional information that must be passed and stored (the angle of the rotation), but that part is very simple, and domain-agnostic. I'm proposing we make this example work and put it in the custom index docs.

I had a go at making that example ([notebook here](https://gist.github.com/TomNicholas/daa15f71e38f07259c6c2e251d0fb38e)) @benbovy, but I'm confused about a couple of things:

1) How do I implement `.sel` in such a way that it supports indexing with slices (i.e. to crop my image)
2) How can I make this lazy?
3) Should the implementation be a ""MetaIndex"" (i.e. wrapping some pandas indexes)?

### Describe the solution you'd like

_No response_

### Describe alternatives you've considered

_No response_

### Additional context

This example is inspired by @jni's use case in napari, where (IIUC) they want to do a lazy functional affine transformation from pixel to physical coordinates, where the simplest example of such a transform might be a linear shear (caused by the imaging focal plane being at an angle to the physical sample).","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/8004/reactions"", ""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue