Using Offset and Origin for Custom Monthly Frequencies in Pandas Grouper

Renaming and Filtering MultiIndex DataFrames with pandas

Grouping Data with pandas: Using `groupby` to Calculate Average and Lists of Rows

Grouping Pandas Rows by a Function of Multiple Columns Using Aggregation Functions and Custom Functions

Grouping by One Column and Summing Elements of Another Column in Pandas with Pivot Tables and Crosstabulations