pandas.errors.DuplicateLabelError

exception pandas.errors.DuplicateLabelError

Error raised when an operation would introduce duplicate labels.

This error is typically encountered when performing operations on objects with allows_duplicate_labels=False and the operation would result in duplicate labels in the index. Duplicate labels can lead to ambiguities in indexing and reduce data integrity.

See also

Series.set_flags

Return a new Series object with updated flags.

DataFrame.set_flags

Return a new DataFrame object with updated flags.

Series.reindex

Conform Series object to new index with optional filling logic.

DataFrame.reindex

Conform DataFrame object to new index with optional filling logic.

Examples

>>> s = pd.Series([0, 1, 2], index=["a", "b", "c"]).set_flags(
...     allows_duplicate_labels=False
... )
>>> s.reindex(["a", "a", "b"])
Traceback (most recent call last):
   ...
DuplicateLabelError: Index has duplicates.
      positions
label
a        [0, 1]