setting values with getattr performs wrong opperation with multi-dimensional coordinate

[d-chambers]

I am using Ubuntu 16, python 3.6, and xarray 0.9.1

Consider the following code:

import xarray as xr
import numpy as np

dims = ['a', 'b']
coords = {'a': range(2), 'b':range(2), 'group': (('a', 'b'), [[0, 0], [0, 1]])}
values = [[0, 0], [0, 0]]

dar = xr.DataArray(values, coords, dims)

dar[dict(group=0)] = 1  # group is only 0 for three of the four elements

expected_values = np.array([[1, 1], [1, 0]])
# yet this raises because all four values are set to 1
assert np.all(np.isclose(dar.values, expected_values))

I suspect trying to assign values in this way using a multi-dimensional coordinate should raise a ValueError as this does:

dar[dict(group=0)]

[shoyer]

Thanks for the report. This should actually raise an error instead -- indexing with coordinates that don't go along a dimension is not supported. For example, note:

In [37]: dar[dict(group=0)]
ValueError: dimensions ['group'] do not exist

[stale]

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[jhamman]

I think this can be safely closed now. Running the example above now raises a ValueError:

dar[dict(group=0)] = 1
...
ValueError: dimensions ['group'] do not exist