Skip to Content
Functional Python Programming - Second Edition
book

Functional Python Programming - Second Edition

by Steven F. Lott
April 2018
Intermediate to advanced content levelIntermediate to advanced
408 pages
10h 42m
English
Packt Publishing
Content preview from Functional Python Programming - Second Edition

Using enumerate() to include a sequence number

Python offers the enumerate() function to apply index information to values in a sequence or iterable. It performs a specialized kind of wrap that can be used as part of an unwrap(process(wrap(data))) design pattern.

It looks like the following code snippet:

>>> xi
[1.47, 1.5, 1.52, 1.55, 1.57, 1.6, 1.63, 1.65, 1.68, 1.7, 1.73,  1.75, 1.78, 1.8, 1.83]
>>> list(enumerate(xi))
[(0, 1.47), (1, 1.5), (2, 1.52), (3, 1.55), (4, 1.57),  (5, 1.6), (6, 1.63), (7, 1.65), (8, 1.68), (9, 1.7),  (10, 1.73), (11, 1.75), (12, 1.78), (13, 1.8), (14, 1.83)]  

The enumerate() function transformed each input item into a pair with a sequence number and the original item. It's vaguely similar to the following:

zip(range(len(source)), ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

Functional Python Programming - Third Edition

Functional Python Programming - Third Edition

Steven F. Lott

Publisher Resources

ISBN: 9781788627061Supplemental Content