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

Writing higher-order mappings and filters

Python's two built-in higher-order functions, map() and filter(), generally handle almost everything we might want to throw at them. It's difficult to optimize them in a general way to achieve higher performance. We'll look at functions of Python 3.4, such as imap(), ifilter(), and ifilterfalse(), in Chapter 8, The Itertools Module.

We have three, largely equivalent ways to express a mapping. Assume that we have some function, f(x), and some collection of objects, C. We have three entirely equivalent ways to express a mapping; they are as follows:

  • The map() function:
map(f, C) 
  • A generator expression:
(f(x) for x in C) 
  • A generator function with a yield statement:
def mymap(f, C): for x in C: ...
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