Data Science Essentials in Python

Unit 35

Ordering and Describing Data

Having the data in a frame is not enough. What we need next is a yardstick that ranks and describes the data that we have. The universal Python yardstick, len, and its brethren, min and max, are a good starting point, but often we want answers to more questions, aside from How many? and How much? pandas provides a number of functions for sorting, ranking, counting, membership testing, and getting descriptive statistics.

Sorting and Ranking

Series and frames can be sorted by index or by value (values). The sort_index function returns a frame sorted by the index (it doesn’t work for series). The sorting order is always lexicographic (numeric for numbers, alphabetic for strings), and you can use the ascending ...