By Michael Nocito , data analyst · Published August 7, 2026 By the end of this page you can take a DataFrame, summarize it by any column or combination of columns, get several statistics at once with sensible names, and account for every row that went in, including the ones pandas would otherwise drop without telling you. It is about twenty-five minutes, and every output shown was produced by actually running the code on the table printed below. Here is what to actually do today. In your ...