Bug in loc did not raise KeyError when missing combination with slice(None) was given #37764
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phofl
added
Indexing
pandas/core/indexing.py
Outdated
| @@ -1107,6 +1107,8 @@ def _getitem_axis(self, key, axis: int): | |||
| # nested tuple slicing | |||
| if is_nested_tuple(key, labels): | |||
| locs = labels.get_locs(key) | |||
| if not len(locs): | |||
| raise KeyError(key) | |||
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if this is going to raise (not 100% sure, but leaning towards yes), i think it should happen in MultiIndex.get_locs
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Could not find any information in the docs, if get_locs should raise when the combination of both keys is not found in MultiIndex. Would prefer that too, but did not want to break anything, hence my question above. Will try to introduce this there
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We are raising in get_locs now. This should be much more stable
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... Edit: Did not think this through. |
| ) | ||
| df = DataFrame(np.random.rand(4, 3), index=mi) | ||
| msg = r"\('b', '1', slice\(None, None, None\)\)" | ||
| with pytest.raises(KeyError, match=msg): |
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can you also add the case where the 3rd level is level out (should also raise)
� Conflicts: � doc/source/whatsnew/v1.2.0.rst
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lgtm @jbrockmendel if any comments. |
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LGTM Thanks for tackling all these indexing issues @phofl, they can be a real doozy. FWIW we've done a lot of semi-recent cleanup of the indexing code but MultiIndex has received relatively little attention. Probably some relatively low-hanging fruit there. |
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Thanks, I will have a look for the MultiIndex code paths |
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@phofl can you merge master, the CI should be fixed |
� Conflicts: � doc/source/whatsnew/v1.2.0.rst
� Conflicts: � doc/source/whatsnew/v1.2.0.rst
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Merged master |
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thanks @phofl |
black pandasgit diff upstream/master -u -- "*.py" | flake8 --diffAdditional question: When an non existent key is given for
get_locsit raises aKeyError. When just a missing combination of keys is given ((b,1)in the new test), while the individual keys exist, an empty array is returned. Is this the expected behavior?