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/4055#issuecomment-628816425,https://api.github.com/repos/pydata/xarray/issues/4055,628816425,MDEyOklzc3VlQ29tbWVudDYyODgxNjQyNQ==,1217238,2020-05-14T18:37:40Z,2020-05-14T18:37:40Z,MEMBER,"If we think can *improve* an error message by adding additional context, the right solution is to use `raise Exception(...) from original_error`:
https://stackoverflow.com/a/16414892/809705
On the other hand, if xarray doesn't have anything more to add on top of the original error message, it is best not to add any wrapper at all. Users will just see the original error from dask.","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628797255,https://api.github.com/repos/pydata/xarray/issues/4055,628797255,MDEyOklzc3VlQ29tbWVudDYyODc5NzI1NQ==,56925856,2020-05-14T18:01:45Z,2020-05-14T18:01:45Z,CONTRIBUTOR,"I also thought that, after the dask error message it's pretty easy to then look at the `dataset` and check what the problem dimension is.
In general though, is that the type of layout you'd suggest for catching and re-raising errors? Using `raise Exception()` ? ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628616379,https://api.github.com/repos/pydata/xarray/issues/4055,628616379,MDEyOklzc3VlQ29tbWVudDYyODYxNjM3OQ==,56925856,2020-05-14T12:57:21Z,2020-05-14T17:50:31Z,CONTRIBUTOR,"Nice, that's neater! Would this work, in the `maybe_chunk()` call? Sorry about the basic questions!
```python
def maybe_chunk(name, var, chunks):
chunks = selkeys(chunks, var.dims)
if not chunks:
chunks = None
if var.ndim > 0:
# when rechunking by different amounts, make sure dask names change
# by provinding chunks as an input to tokenize.
# subtle bugs result otherwise. see GH3350
token2 = tokenize(name, token if token else var._data, chunks)
name2 = f""{name_prefix}{name}-{token2}""
try:
return var.chunk(chunks, name=name2, lock=lock)
except NotImplementedError as err:
raise Exception(""Automatic chunking fails for object arrays.""
+ ""These include cftime DataArrays."")
else:
return var
```","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628747933,https://api.github.com/repos/pydata/xarray/issues/4055,628747933,MDEyOklzc3VlQ29tbWVudDYyODc0NzkzMw==,1217238,2020-05-14T16:31:39Z,2020-05-14T16:31:39Z,MEMBER,"The error message from dask is already pretty descriptive:
`NotImplementedError: Can not use auto rechunking with object dtype. We are unable to estimate the size in bytes of object data`
I don't think we have much to add on top of that?","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628582552,https://api.github.com/repos/pydata/xarray/issues/4055,628582552,MDEyOklzc3VlQ29tbWVudDYyODU4MjU1Mg==,2448579,2020-05-14T11:51:21Z,2020-05-14T11:51:21Z,MEMBER,"`is_scalar(chunks)` might be the appropriate condition. `is_scalar` is already imported from `.utils` in `dataset.py`
> This seems to work fine in a lot of cases, except automatic chunking isn't implemented for object dtypes at the moment, so it fails if you pass a cftime coordinate, for example.
Can we catch this error and re-raise specifying ""automatic chunking fails for object arrays. These include cftime DataArrays"" or something like that?
","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628513777,https://api.github.com/repos/pydata/xarray/issues/4055,628513777,MDEyOklzc3VlQ29tbWVudDYyODUxMzc3Nw==,56925856,2020-05-14T09:26:24Z,2020-05-14T09:26:24Z,CONTRIBUTOR,"Also, the contributing docs have been super clear so far! Thanks! :)","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628513443,https://api.github.com/repos/pydata/xarray/issues/4055,628513443,MDEyOklzc3VlQ29tbWVudDYyODUxMzQ0Mw==,56925856,2020-05-14T09:25:48Z,2020-05-14T09:25:48Z,CONTRIBUTOR,"Cheers! Just had a look, is it as simple as just changing this line to the following, @dcherian ?
```python
if isinstance(chunks, Number) or chunks=='auto':
chunks = dict.fromkeys(self.dims, chunks)
```
This seems to work fine in a lot of cases, except automatic chunking isn't implemented for `object` dtypes at the moment, so it fails if you pass a `cftime` coordinate, for example.
One option is to automatically use `self=xr.decode_cf(self)` if the input dataset is cftime? Or could just throw an error.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628319690,https://api.github.com/repos/pydata/xarray/issues/4055,628319690,MDEyOklzc3VlQ29tbWVudDYyODMxOTY5MA==,1217238,2020-05-14T00:43:22Z,2020-05-14T00:43:22Z,MEMBER,"Agreed, this would be very welcome!
`chunks='auto'` isn't supported only because xarray support for dask predates it :)","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628231949,https://api.github.com/repos/pydata/xarray/issues/4055,628231949,MDEyOklzc3VlQ29tbWVudDYyODIzMTk0OQ==,2448579,2020-05-13T20:35:49Z,2020-05-13T20:35:49Z,MEMBER,Awesome! Please see https://xarray.pydata.org/en/stable/contributing.html for docs on contributing,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628212516,https://api.github.com/repos/pydata/xarray/issues/4055,628212516,MDEyOklzc3VlQ29tbWVudDYyODIxMjUxNg==,56925856,2020-05-13T19:56:34Z,2020-05-13T19:56:34Z,CONTRIBUTOR,"Oh ok I didn't know about this, I'll take a look and read the contribution docs tomorrow ! It'll be my first PR so may need a bit of hand-holding when it comes to tests. Willing to try though!","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316
https://github.com/pydata/xarray/issues/4055#issuecomment-628065564,https://api.github.com/repos/pydata/xarray/issues/4055,628065564,MDEyOklzc3VlQ29tbWVudDYyODA2NTU2NA==,2448579,2020-05-13T15:26:10Z,2020-05-13T15:26:49Z,MEMBER,"so `da.chunk({dim_name: ""auto""})` works but `da.chunk(""auto"")` does not. The latter is a relatively easy fix. We just need to update the condition here:
https://github.com/pydata/xarray/blob/bd84186acbd84bd386134a5b60111596cee2d8ec/xarray/core/dataset.py#L1736-L1737
A PR would be very welcome if you have the time, @AndrewWilliams3142","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,617476316