Function reduce_exprs

pub fn reduce_exprs<F, E>(f: F, exprs: E) -> Expr
where
    F: 'static + Fn(Column, Column) -> Result<Option<Column>, PolarsError> + Send + Sync,
    E: AsRef<[Expr]>,

Available on crate feature lazy only.

Analogous to Iterator::reduce.

An accumulator is initialized to the series given by the first expression in exprs, and then each subsequent value of the accumulator is computed from f(acc, next_expr_series). If exprs is empty, an error is returned when collect is called.