Pandas

From your first DataFrame to groupby, merging, and time series. Go through each lesson in order: read, run the examples yourself, then work the exercises at the bottom. Prefer a dense lookup instead? Jump to the quick reference.

Beginner

1. Series & DataFrames

The two core pandas structures, and what's actually inside a DataFrame.

2. Selection & Filtering

loc vs. iloc, and filtering rows with boolean conditions.

Intermediate

3. Missing Data & Transformations

Finding and filling gaps, plus the vectorized way to change values.

4. GroupBy & Aggregation

Split-apply-combine: pandas' most powerful single idea.

Advanced

5. Merging, Joining & Reshaping

Combining multiple DataFrames, and pivoting between long and wide.

6. Time Series & MultiIndex

Working with dates, and indexing by more than one level at once.