issues: 289790965

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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
289790965 MDU6SXNzdWUyODk3OTA5NjU= 1838 DataArray.sum does not respect dtype keyword 500246 closed 0     2 2018-01-18T22:01:07Z 2018-01-20T18:29:02Z 2018-01-20T18:29:02Z CONTRIBUTOR      

Code Sample, a copy-pastable example if possible

```python

Your code here

da = xarray.DataArray(arange(5, dtype="i2")) print(da.sum(dtype="i4").dtype) ```

Problem description

The result is int64. This is a problem because I asked for int32.

Expected Output

Expected output int32.

Output of xr.show_versions()

# Paste the output here xr.show_versions() here INSTALLED VERSIONS ------------------ commit: None python: 3.6.1.final.0 python-bits: 64 OS: Linux OS-release: 2.6.32-696.6.3.el6.x86_64 machine: x86_64 processor: x86_64 byteorder: little LC_ALL: None LANG: en_GB.UTF-8 LOCALE: en_GB.UTF-8 xarray: 0.10.0+dev12.gf882a58 pandas: 0.22.0 numpy: 1.14.0 scipy: 1.0.0 netCDF4: 1.3.1 h5netcdf: None Nio: None bottleneck: 1.2.1 cyordereddict: None dask: 0.16.1 matplotlib: 2.1.1 cartopy: 0.15.1 seaborn: 0.8.1 setuptools: 38.4.0 pip: 9.0.1 conda: 4.3.16 pytest: 3.1.2 IPython: 6.1.0 sphinx: 1.6.2 
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   completed 13221727 issue

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