html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/issues/4562#issuecomment-970851123,https://api.github.com/repos/pydata/xarray/issues/4562,970851123,IC_kwDOAMm_X8453gMz,20617032,2021-11-16T23:39:09Z,2021-11-16T23:39:09Z,NONE,"I tested the method of adding a new level with `mi.values`, which worked, though `x='x'` must still be specified:

```
import numpy as np
import pandas as pd
import xarray as xr

data = np.random.rand(50,5)

x_idx = np.linspace(0, 50)

mi_idx1 = ['a','b','c','d','e']
mi_idx2 = [1,2,3,4,5]

mi = pd.MultiIndex.from_arrays([mi_idx1,mi_idx2], names=['mi_idx1', 'mi_idx2'])

coords = {
    'x': x_idx,
    'mi': mi
}

da = xr.DataArray(data, coords=coords, dims = ['x', 'mi'])

da = da.assign_coords(mi_plot = ('mi', da.indexes['mi'].values)) # add a level for plot display

da.plot(hue='mi_plot', x='x')
```

It seems like this potentially happen behind the scenes, but I'm not sure. 
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,735523592
https://github.com/pydata/xarray/issues/4562#issuecomment-728363355,https://api.github.com/repos/pydata/xarray/issues/4562,728363355,MDEyOklzc3VlQ29tbWVudDcyODM2MzM1NQ==,20617032,2020-11-16T22:17:28Z,2020-11-16T22:18:28Z,NONE,"I tested this (`hue=""mi_idx1""`)  and it does not work. 

I get the following error on 0.15.1: 

`ValueError: y must be a dimension name if x is not supplied`

and on 0.16.1:

`ValueError: ('mi', 'mi') must be a permuted list of ('x', 'mi'), unless `...` is included`


(also, sorry, I accidentally clicked close and comment)","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,735523592
https://github.com/pydata/xarray/issues/4562#issuecomment-721360380,https://api.github.com/repos/pydata/xarray/issues/4562,721360380,MDEyOklzc3VlQ29tbWVudDcyMTM2MDM4MA==,20617032,2020-11-03T20:34:02Z,2020-11-03T20:34:02Z,NONE,"> It makes sense to allow a MultiIndex as a label but probably not as a coordinate

To elaborate a little more on my particular use case, as it might give insight or an alternative solution: I often have time data taken under different experimental parameters, which are my coordinates. However, often the coordinate matrix is very sparse, meaning that my coordinate matrix might be 5x5x5, but I only have 10 data points or so somewhat randomly sampling this space. So being able to see all my 'test cases' with respect to hue/col etc is very useful to quickly examine the data and coordinate combinations, which helps once I want to unstack the array deal with all of the empty parameter space. ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,735523592