issues: 241389297

This data as json

id node_id number title user state locked assignee milestone comments created_at updated_at closed_at author_association active_lock_reason draft pull_request body reactions performed_via_github_app state_reason repo type
241389297 MDU6SXNzdWUyNDEzODkyOTc= 1472 .sel(drop=True) fails to drop coordinate 3698640 closed 0     4 2017-07-07T21:49:35Z 2017-07-10T16:08:30Z 2017-07-10T15:54:23Z CONTRIBUTOR      

Using both xarray 0.9.6 and current (0.9.6-16-gb201ff7), da.sel(drop=True, **indexers) and da.isel(drop=True, **indexers) return unexpectedly different results.

Setup:

```python In [1]: import xarray as xr, pandas as pd, numpy as np

In [2]: years = pd.Index( ...: pd.date_range('1981-01-01', '2100-01-01', freq='A', closed='left'), ...: name='time') ...: ages = pd.Index(['age0', 'age1', 'age2', 'age3'], name='age')

In [3]: arr = xr.DataArray( ...: np.random.random((len(years), 4)), dims=('time', 'age'), ...: coords={'time': years, 'age': ages})

In [4]: arr Out[4]: <xarray.DataArray (time: 119, age: 4)> array([[ 0.755194, 0.1316 , 0.283485, 0.616929], [ 0.01667 , 0.907853, 0.667366, 0.146755], [ 0.338319, 0.782972, 0.367624, 0.390907], ..., [ 0.453521, 0.807693, 0.094811, 0.603297], [ 0.405114, 0.821691, 0.633314, 0.259406], [ 0.41722 , 0.012957, 0.329089, 0.774966]]) Coordinates: * age (age) object 'age0' 'age1' 'age2' 'age3' * time (time) datetime64[ns] 1981-12-31 1982-12-31 1983-12-31 ... ```

I would expect the following operations to return identical results:

```python In [5]: arr.sel(time='2012', drop=True) Out[5]: <xarray.DataArray (time: 1, age: 4)> array([[ 0.086045, 0.467905, 0.101005, 0.503311]]) Coordinates: * age (age) object 'age0' 'age1' 'age2' 'age3' Dimensions without coordinates: time

In [6]: arr.isel(time=31, drop=True) Out[6]: <xarray.DataArray (age: 4)> array([ 0.086045, 0.467905, 0.101005, 0.503311]) Coordinates: * age (age) object 'age0' 'age1' 'age2' 'age3' `` Note thattimeis still seen as a dimension in in the.sel` results.

The same behavior is seen for Dataset.sel(drop=true):

```python In [7]: ds = xr.Dataset({'arr': arr})

In [8]: ds.sel(time='2012', drop=True) Out[8]: <xarray.Dataset> Dimensions: (age: 4, time: 1) Coordinates: * age (age) object 'age0' 'age1' 'age2' 'age3' Dimensions without coordinates: time Data variables: arr (time, age) float64 0.08604 0.4679 0.101 0.5033

In [9]: ds.isel(time=31, drop=True) Out[9]: <xarray.Dataset> Dimensions: (age: 4) Coordinates: * age (age) object 'age0' 'age1' 'age2' 'age3' Data variables: arr (age) float64 0.08604 0.4679 0.101 0.5033 ```

 
{
    "url": "https://api.github.com/repos/pydata/xarray/issues/1472/reactions",
    "total_count": 0,
    "+1": 0,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
   completed 13221727 issue

Links from other tables