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/5215#issuecomment-826364666,https://api.github.com/repos/pydata/xarray/issues/5215,826364666,MDEyOklzc3VlQ29tbWVudDgyNjM2NDY2Ng==,2448579,2021-04-25T18:05:55Z,2021-04-25T18:05:55Z,MEMBER,"IIUC `da.expanding(dim=dim).sum()` is `da.cumsum(dim)` with support for `min_periods` and `center` like `rolling`.

I guess all expanding reductions are basically `numpy.ufunc.accumulate(...)`. The dask versions will be ""interesting"" to write.
https://github.com/dask/dask/blob/f1f37cae96d5e98f8043ea430539a4fffbe62661/dask/array/reductions.py#L1389-L1413

Like @mathause I find ""expanding"" confusing. `.accumulate().sum()` or `.cumulative().sum()` sounds much better to me.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,866826033