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 exercício faz parte do curso
Data Transformation with Polars
Instruções do exercício
- Add a column
cumulative_rentalswith the cumulative sum ofrentals.
Exercício interativo prático
Experimente este exercício completando este código de exemplo.
# Add a cumulative sum of rentals
bikes.with_columns(
pl.col("rentals").____().alias("____")
)