It's intended to be a library for working with data stored in multi dimensional in-memory tables. Think loading a .csv file or relational table into memory, performing some transformations, adding columns, merging with other tables, and grouping data, filtering, sorting, all while handling missing data gracefully.

Maybe I would describe it as combing a spreadsheet with SQL data transformation capabilities - but better.

It requires numpy because it uses ndarray as it's underlying data structure and you can also use many/most? of the numpy data analysis functions.

It requires numpy. Check out the linked article...