Return unique values in the index. Unique values are returned in order of appearance, this does NOT sort. Parameters ---------- level : int or hashable, optional Only return values from specified level (for MultiIndex). If int, gets
(self, level: Hashable | None = None)
| 2815 | # Uniqueness Methods |
| 2816 | |
| 2817 | def unique(self, level: Hashable | None = None) -> Self: |
| 2818 | """ |
| 2819 | Return unique values in the index. |
| 2820 | |
| 2821 | Unique values are returned in order of appearance, this does NOT sort. |
| 2822 | |
| 2823 | Parameters |
| 2824 | ---------- |
| 2825 | level : int or hashable, optional |
| 2826 | Only return values from specified level (for MultiIndex). |
| 2827 | If int, gets the level by integer position, else by level name. |
| 2828 | |
| 2829 | Returns |
| 2830 | ------- |
| 2831 | Index |
| 2832 | Unique values in the index. |
| 2833 | |
| 2834 | See Also |
| 2835 | -------- |
| 2836 | unique : Numpy array of unique values in that column. |
| 2837 | Series.unique : Return unique values of Series object. |
| 2838 | |
| 2839 | Examples |
| 2840 | -------- |
| 2841 | >>> idx = pd.Index([1, 1, 2, 3, 3]) |
| 2842 | >>> idx.unique() |
| 2843 | Index([1, 2, 3], dtype='int64') |
| 2844 | """ |
| 2845 | if level is not None: |
| 2846 | self._validate_index_level(level) |
| 2847 | |
| 2848 | if self.is_unique: |
| 2849 | return self._view() |
| 2850 | |
| 2851 | result = super().unique() |
| 2852 | return self._shallow_copy(result) |
| 2853 | |
| 2854 | def drop_duplicates(self, *, keep: DropKeep = "first") -> Self: |
| 2855 | """ |