issue_comments

I fixed my conda environment now (something was wrong as I appeared to have two xarray installations in parallel). I still get the KeyError with latest xarray master and latest pandas master:

$ conda list | egrep -w '(pandas|xarray)' pandas 1.2.0.dev0+167.g1f35b0621 pypi_0 pypi xarray 0.16.1.dev65+g13caf96e pypi_0 pypi $ python mwe83.py Traceback (most recent call last): File "mwe83.py", line 5, in <module> da.sel(time=da.coords["time"][0]) File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/dataarray.py", line 1142, in sel ds = self._to_temp_dataset().sel( File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/dataset.py", line 2096, in sel pos_indexers, new_indexes = remap_label_indexers( File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/coordinates.py", line 395, in remap_label_indexers pos_indexers, new_indexes = indexing.remap_label_indexers( File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/indexing.py", line 270, in remap_label_indexers idxr, new_idx = convert_label_indexer(index, label, dim, method, tolerance) File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/indexing.py", line 189, in convert_label_indexer indexer = index.get_loc( File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/pandas/core/indexes/datetimes.py", line 622, in get_loc raise KeyError(key) KeyError: 0 $ cat mwe83.py import xarray as xr import numpy as np da = xr.DataArray([0, 1], dims=("time",), coords={"time": np.array([0, 1], dtype="M8[s]")}) da.sel(time=slice(da.coords["time"][0], da.coords["time"][1])) da.sel(time=da.coords["time"][0])

Oops, by "already have" you meant it's already been reported, I thought you meant it had already been fixed. All clear then.

What's your pandas version? If it's pandas>=1.1.0, we already have #4283. Otherwise you might want to update your repository, we're at 13caf96efb3f121e232a35aafceed80c832a9876 right now (the latest release is 0.16.0).

This was closed and was solved for slicing, but not for element indexing:

python import xarray as xr import numpy as np da = xr.DataArray([0, 1], dims=("time",), coords={"time": np.array([0, 1], dtype="M8[s]")}) da.sel(time=da.coords["time"][0])

results in

Traceback (most recent call last): File "mwe83.py", line 4, in <module> da.sel(time=da.coords["time"][0]) File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/dataarray.py", line 1142, in sel ds = self._to_temp_dataset().sel( File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/dataset.py", line 2096, in sel pos_indexers, new_indexes = remap_label_indexers( File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/coordinates.py", line 395, in remap_label_indexers pos_indexers, new_indexes = indexing.remap_label_indexers( File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/indexing.py", line 270, in remap_label_indexers idxr, new_idx = convert_label_indexer(index, label, dim, method, tolerance) File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/xarray/core/indexing.py", line 189, in convert_label_indexer indexer = index.get_loc( File "/data/gholl/miniconda3/envs/py38/lib/python3.8/site-packages/pandas/core/indexes/datetimes.py", line 622, in get_loc raise KeyError(key) KeyError: 0

using xarray 0.15.2.dev64+g2542a63f (latest master). I think it would be desirable that it works in both cases. Should we reopen this issue or should I open a new?

Sorry for letting this one linger for so long... I added the "bug" tag so we don't forget about it for the next release.

@jhamman - thanks, this should be usefull...

@ulijh - you should be able to use the time index:

Python In [11]: arr.loc[arr.indexes['time'][2]:arr.indexes['time'][5]] Out[11]: <xarray.DataArray (time: 4, space: 3)> array([[ 0.422991, 0.513276, 0.762432], [ 0.111123, 0.371109, 0.697921], [ 0.029415, 0.215116, 0.451697], [ 0.670181, 0.855551, 0.319134]]) Coordinates: * time (time) datetime64[ns] 2000-01-03 2000-01-04 2000-01-05 2000-01-06 * space (space) <U2 'IA' 'IL' 'IN'

Hi, this is still the case for version 0.10.0. arr = xr.DataArray(np.random.rand(10, 3), ...: [('time', pd.date_range('2000-01-01', periods=10)), ...: ('space', ['IA', 'IL', 'IN'])]) ...: arr.loc[arr.time[2]:arr.time[5]] fails, but doing the same thing on a pandas dataframe works just fine: dfr = arr.to_dataframe(name='dfr') dfr.loc[arr.time[2]:arr.time[5]] I'd really appreciate see this working on a DataArray.

I get the same error when trying to do: depo[depo.sel(time=slice(tmp.time[0],tmp.time[-1]))] = tmp Where both depo and tmp are DataArrays. Do you have an example solution/workaround?

Yes, this is annoying. We already have some work arounds for this in xarray -- see _as_array_or_item in xarray/core/variable.py. I would be happy to add a similar work around to fix slicing.