issue_comments: 680940858

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https://github.com/pydata/xarray/issues/4372#issuecomment-680940858 https://api.github.com/repos/pydata/xarray/issues/4372 680940858 MDEyOklzc3VlQ29tbWVudDY4MDk0MDg1OA== 2448579 2020-08-26T15:10:05Z 2020-08-26T15:10:05Z MEMBER

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I am pretty confident that existing behavior of xarray.apply_ufunc with un-equal chunks along non-core dimensions is entirely broken. I am OK with just erroring for now.

@shoyer could you please clarify what you meant?

For example, this works with v0.16.0 but fails on master ``` python import operator

import numpy as np

import xarray as xr

a = xr.DataArray(np.ones((10, 10)), dims=("a", "b")).chunk({"a": 2, "b": 1}) b = xr.DataArray(np.ones((10, 10)), dims=("a", "b")).chunk({"a": -1, "b": 4})

xr.apply_ufunc( operator.add, a, b, dask="parallelized", output_dtypes=[a.dtype], ).compute().equals(a.compute() + b.compute()) ```

 
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