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/7193#issuecomment-1287593498,https://api.github.com/repos/pydata/xarray/issues/7193,1287593498,IC_kwDOAMm_X85Mvx4a,38346144,2022-10-22T02:51:50Z,2022-10-22T09:51:43Z,NONE,"> Thanks @weipeng1999 . Can you please provide a minimal example showing the syntax and expected output?

Can I just copy from the [doc](https://docs.xarray.dev/en/stable/user-guide/indexing.html#more-advanced-indexing) and use comment to mention the change
``` python
In [100]: da = xr.DataArray(
    ....:     np.random.rand(4, 2),
    ....:     [
    ....:         (""time"", pd.date_range(""2000-01-01"", periods=4)),
    ....:         (""space"", [""IA"", ""IL""]), # do not have the ""IN"" label
    ....:     ],
    ....: )

In [101]: times = xr.DataArray(
    ....:     pd.to_datetime([""2000-01-03"", ""2000-01-02"", ""2000-01-01""]), dims=""new_time""
    ....: )

In [102]: # use .reindex instead of .sel
    ....: # and give the parameter : ""fill_value""
    ....: da.reindex(space=xr.DataArray([""IA"", ""IL"", ""IN""], dims=[""new_time""]), time=times, fill_value=np.nan)
Out[102]: 
<xarray.DataArray (new_time: 3)>
array([0.92, 0.34, NaN]) # so fill the missing value by np.nan
Coordinates:
    time      (new_time) datetime64[ns] 2000-01-03 2000-01-02 2000-01-01
    space     (new_time) <U2 'IA' 'IL' 'IN'
  * new_time  (new_time) datetime64[ns] 2000-01-03 2000-01-02 2000-01-01

```","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1417641930
https://github.com/pydata/xarray/issues/7193#issuecomment-1287594393,https://api.github.com/repos/pydata/xarray/issues/7193,1287594393,IC_kwDOAMm_X85MvyGZ,38346144,2022-10-22T02:57:50Z,2022-10-22T02:57:50Z,NONE,"So we can guarantee that:

- .reindex: set the missing value to fill_value (derfault is nan), and the result data may have nan.
- .fillna: deal the nan in data and the result data will not have nan.
- .sel: do not change the state.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1417641930
https://github.com/pydata/xarray/issues/7193#issuecomment-1287284625,https://api.github.com/repos/pydata/xarray/issues/7193,1287284625,IC_kwDOAMm_X85MumeR,2448579,2022-10-21T18:08:16Z,2022-10-21T18:08:16Z,MEMBER,Thanks @weipeng1999 . Can you please provide a minimal example showing the syntax and expected output?,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1417641930