Calculating cumulative rentals
Rolling sums smooth short-term noise, but sometimes you need the running total from the very start. Cumulative sums track how usage builds up over time, useful for capacity planning and monthly reporting.
polars is loaded as pl. The DataFrame bikes is available with columns time, rentals, and temp.
Este ejercicio forma parte del curso
Data Transformation with Polars
Instrucciones del ejercicio
- Add a column
cumulative_rentalswith the cumulative sum ofrentals.
Ejercicio interactivo práctico
Prueba este ejercicio y completa el código de muestra.
# Add a cumulative sum of rentals
bikes.with_columns(
pl.col("rentals").____().alias("____")
)