polars.arg_where#
- polars.arg_where(condition: polars.internals.expr.expr.Expr | polars.internals.series.series.Series, eager: Literal[False] = False) Expr [source]#
- polars.arg_where(condition: polars.internals.expr.expr.Expr | polars.internals.series.series.Series, eager: Literal[True]) Series
- polars.arg_where(condition: polars.internals.expr.expr.Expr | polars.internals.series.series.Series, eager: bool) polars.internals.expr.expr.Expr | polars.internals.series.series.Series
Return indices where condition evaluates True.
- Parameters:
- condition
Boolean expression to evaluate
- eager
Whether to apply this function eagerly (as opposed to lazily).
Examples
>>> df = pl.DataFrame({"a": [1, 2, 3, 4, 5]}) >>> df.select( ... [ ... pl.arg_where(pl.col("a") % 2 == 0), ... ] ... ).to_series() shape: (2,) Series: 'a' [u32] [ 1 3 ]