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Company
Topic
Difficulty
GooglePandasMedium
Compute rolling 7-day average
Given a DataFrame with columns 'date' (datetime) and 'revenue' (float), write a query that adds a column 'revenue_7d_avg' containing the 7-day rolling average of revenue, sorted by date.
PYTHON
rolling(7):Window size must be 7 days
First 6 rows NaN:Rolling window starts returning values only after 7 data points