polars.cumreduce#

polars.cumreduce(
function: Callable[[Series, Series], Series],
exprs: Sequence[Expr | str] | Expr,
) Expr[source]#

Cumulatively accumulate over multiple columns horizontally/ row wise with a left fold.

Every cumulative result is added as a separate field in a Struct column.

Parameters:
function

Function to apply over the accumulator and the value. Fn(acc, value) -> new_value

exprs

Expressions to aggregate over. May also be a wildcard expression.