issues: 111471076

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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
111471076 MDU6SXNzdWUxMTE0NzEwNzY= 624 roll method 1197350 closed 0     8 2015-10-14T19:14:36Z 2015-12-02T23:32:28Z 2015-12-02T23:32:28Z MEMBER      

I would like to pick up my idea to add a roll method. Among many uses, it could help with #623.

The method is pretty simple.

python def roll(darr, n, dim): """Clone of numpy.roll for xray objects.""" left = darr.isel(**{dim: slice(None, -n)}) right = darr.isel(**{dim: slice(-n, None)}) return xray.concat([right, left], dim=dim, data_vars='minimal', coords='minimal')

I have already been using this function a lot (defined from outside xray) and find it quite useful. I would like to create a PR to add it, but I am having a little trouble understanding how to correctly "inject" it into the api. A few words of advice from @shoyer would probably save me a lot of trial and error.

 
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