Better default behavior of the Coordinates constructor #8107
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... for any input dimension coordinate, if ``indexes=None``. Also, if another ``Coordinates`` object is passed, extract its indexes and raise if ``indexes`` is not None (no align/merge supported here).
I also think this is totally fine. |
| variables = {k: as_variable(v) for k, v in coords.items()} | ||
| variables = {} | ||
| for name, data in coords.items(): | ||
| var = as_variable(data, name=name) |
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This still converts any coordinate input in the form {"x": array_like} to an IndexVariable, which triggers data loading by coercing array_like to a pd.Index.
It will be fixed in another PR (#8124).
As a workaround, {"x": ("x", array_like)} does not coerce array_like.
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@benbovy I'm pretty sure this workaround currently does not work. I tried to create a Coordinates object from scratch with no indexes and the only way I was able to do it required reverting xarray to v2023.08.0, i.e. just before this PR was merged.
See the end of https://gist.github.com/TomNicholas/d9eb8ac81d3fd214a23b5e921dbd72b7 for full context.
* ``Coordinates.__init__`` create default indexes ... for any input dimension coordinate, if ``indexes=None``. Also, if another ``Coordinates`` object is passed, extract its indexes and raise if ``indexes`` is not None (no align/merge supported here). * add docstring examples * fix doctests * fix tests * update what's new
* as_variable: deprecate converting to IndexVariable * fix multi-index edge case * Better default behavior of the Coordinates constructor (#8107) * ``Coordinates.__init__`` create default indexes ... for any input dimension coordinate, if ``indexes=None``. Also, if another ``Coordinates`` object is passed, extract its indexes and raise if ``indexes`` is not None (no align/merge supported here). * add docstring examples * fix doctests * fix tests * update what's new * fix deprecation warning after unintentionally reverted a valid previous change. * avoid unnecessary auto-creation of index to avoid userwarning * catch expected FutureWarnings in test_as_variable * check for coercion to IndexVariable * whatsnew --------- Co-authored-by: Benoit Bovy <benbovy@gmail.com>
whats-new.rstAfter working more on
CoordinatesI realize that the default behavior of its constructor could be more consistent with other Xarray objects. This PR changes this default behavior such that:indexes=None(default). To create dimension coordinates with no index, just passindexes={}.Coordinatesobject is passed as input, its indexes are also added to the new created object. Since we don't support alignment / merge here, the following call raises an error:xr.Coordinates(coords=xr.Coordinates(...), indexes={...}).This PR introduces a breaking change since
Coordinatesare now exposed in v2023.8.0, which has just been released. It is a bit unfortunate but I think it may be OK for a fresh feature, especially if the next release will be soon after this one.