Examples

• Aggregate with expressions

  Summarize the Palmer penguins by species with several expressions in one grouped aggregation.

• Query a large CSV file lazily

  Count late departures from each New York City airport in the 33 MB nycflights13 flights file with a lazy query plan.

• Rolling windows and as-of joins

  Match JFK departures to the latest weather reading and a 3-hour rolling mean of temperature.

• Fit a mixed model to a Polars table and chart it · from phit

  Read sleepstudy with Polars, fit subject intercepts, and chart one fitted line per subject.