Clarify rules for copies vs views when indexing #512
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@jhamman any thoughts? |
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| Like pandas, whether array indexing returns a view or a copy of the underlying | ||
| data depends entirely on numpy: | ||
| The label based selection methods :py:meth:`~xray.Dataset.sel`, |
| * Label-based indexing with arrays returns a copy. | ||
| * Label-based indexing with scalars returns a view or a copy, depending | ||
| upon if the corresponding positional indexer can be represented as an | ||
| integer or a slice object. |
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for the last point, an example showing both behaviors may be helpful.
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unfortunately, the distinction here is pretty complex and I'm not even sure I understand it fully...
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I made a few comments. I think you'll have to sort out the merge conflicts coming from #507. |
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Revised and rebased. |
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I'm not able to build the docs from where I am but from what I can tell, this looks good. |
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Clarify rules for copies vs views when indexing
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This mostly reorganizes/updates the indexing documentation.
It also catches an edge case where a slice based indexer could be converted silently into array indexer. This is a strange edge case involving unsorted or duplicate indexes that arguably pandas shouldn't allow anyways.