polars.Series.cat.set_ordering

Series.cat.set_ordering(ordering: CategoricalOrdering) → Series

Determine how this categorical series should be sorted.

Parameters:

ordering{‘physical’, ‘lexical’}

Ordering type:

• ‘physical’ -> Use the physical representation of the categories to

  determine the order (default).

• ‘lexical’ -> Use the string values to determine the ordering.

Examples

>>> df = pl.DataFrame(
...     {"cats": ["z", "z", "k", "a", "b"], "vals": [3, 1, 2, 2, 3]}
... ).with_columns(
...     [
...         pl.col("cats").cast(pl.Categorical).cat.set_ordering("lexical"),
...     ]
... )
>>> df.sort(["cats", "vals"])
shape: (5, 2)
┌──────┬──────┐
│ cats ┆ vals │
│ ---  ┆ ---  │
│ cat  ┆ i64  │
╞══════╪══════╡
│ a    ┆ 2    │
│ b    ┆ 3    │
│ k    ┆ 2    │
│ z    ┆ 1    │
│ z    ┆ 3    │
└──────┴──────┘