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/386#issuecomment-91679470,https://api.github.com/repos/pydata/xarray/issues/386,91679470,MDEyOklzc3VlQ29tbWVudDkxNjc5NDcw,1217238,2015-04-10T20:37:43Z,2015-04-10T20:37:43Z,MEMBER,"Resampling actually supports custom aggregation methods with the `how` parameter: http://xray.readthedocs.org/en/stable/generated/xray.Dataset.resample.html#xray.Dataset.resample ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,67332234 https://github.com/pydata/xarray/issues/386#issuecomment-91355259,https://api.github.com/repos/pydata/xarray/issues/386,91355259,MDEyOklzc3VlQ29tbWVudDkxMzU1MjU5,1217238,2015-04-09T21:01:04Z,2015-04-09T21:01:04Z,MEMBER,"The better solution here is to use `resample` rather than `groupby('time.date')`: ``` ts_mean = ts.resample('1D', dim='time') ``` `time.date` and `time.time` (with is currently broken) are weird virtual variables, because, like you point out, they create object arrays. That makes them not so useful. It might be better to get rid of them entirely, or to replace them with some sort of shortcut that returns datetime64 instead. ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,67332234