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.

Deprecated since version 0.19.14: This function has been renamed to cum_reduce().

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.