How to Apply Custom Functions on Polars Groups (.group_by().apply())
We know that .map_elements() is slow because it runs row-by-row. We know that .group_by().agg() is super fast, but it’s limited to simple functions (like sum,…

We know that .map_elements() is slow because it runs row-by-row. We know that .group_by().agg() is super fast, but it’s limited to simple functions (like sum,…

The most common data analysis task is “Split-Apply-Combine.” When using Polars, the groupby operation is essential for this task. In Polars, this is done with…

Loading data is easy. Summarizing it is where the value lies, and that’s where Pandas groupby can make a big difference. If you have a…