midPandas
What is window function in Pandas?
Updated May 17, 2026
Short answer
Window functions perform rolling or expanding computations over data.
Deep explanation
They allow calculations like moving averages, rolling sums, or exponential smoothing over a defined window size.
Real-world example
Calculating 7-day moving average of sales.
Common mistakes
- Ignoring NaN values in early windows.
Follow-up questions
- What is expanding window?
- What is rolling window?