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
1949782787,PR_kwDOAMm_X85dJLvY,8332,Add invert option to DataArray/Dataset.stack(),92899389,open,0,,,9,2023-10-18T13:38:38Z,2024-04-29T16:29:40Z,,FIRST_TIME_CONTRIBUTOR,,0,pydata/xarray/pulls/8332,"This brings in the option to stack all dimensions *except* for one or more dimensions listed. I find this very useful for quickly iterating over all the combinations of dimensions except for one (i.e. you have a number of input parameters that are parameterized and one time dimension, and you want to calculate some time response for all the combinations of these input parameters and store them in the time-row corresponding to the appropriate combination of inputs).

I played around with implementing `to_stacked_array()` for `DataArray`, but this made less sense in the end since that method was really designed for Datasets.

- [x] Addresses #8278
- [ ] Tests added (added one for DataArray, just now realizing I should have one for Dataset)
- [ ] User visible changes (including notable bug fixes) are documented in `whats-new.rst`
- [ ] New functions/methods are listed in `api.rst`
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/8332/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,pull
1930702782,I_kwDOAMm_X85zFC--,8278,A way to `stack` all dimensions but one?,92899389,closed,0,,,3,2023-10-06T17:48:18Z,2023-10-06T20:58:20Z,2023-10-06T20:58:20Z,NONE,,,,"### Is your feature request related to a problem?

One thing I find useful with `DataArrays` is the ability to take all dimensions but one, `stack` them into one `MultiIndex`, and then iterate over the entries of that `MultiIndex`. For example, I have a `DataArray` that starts with a `time` dimension/coordinate. I then add several new dimensions/coords that correspond to varying input parameters (i.e. one for initial velocity, initial position, air density, etc.). What I then want to do is iterate over all 1D `time` vectors (all the combinations of those variable input parameters). The easiest way I've found to do this is to `stack` all the dimensions except `time` and then iterate over the resulting `MultiIndex`. I have been doing this by converting the `dims` of the `DataArray` to a `list` and then removing `""time""` from that list and using it as the input to `stack`.

### Describe the solution you'd like

It would be awesome if there was a method that could specifically stack all dimensions except for a list of specified dimension names (something like `DataArray.stack_except({""name_of_created_stacked_dimension"": [""dim_to_leave_unstacked"", ""another_dim""])`), or some kind of syntax that would allow an ""all except"" behavior to be passed directly into `stack` (could be something like `DataArray.stack({""name_of_created_stacked_dimension""}: [""dim_to_leave_unstacked""], invert=True).

### Describe alternatives you've considered

If there is a better way to achieve what I'm trying to accomplish (take one dimension and iterate over all the combinations of the other dimensions, resulting in 1D vectors that vary along the single desired dimension), then I would welcome any tips!

### Additional context

_No response_","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/8278/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,completed,13221727,issue