This is a pre-production deployment of Warehouse, however changes made here WILL affect the production instance of PyPI.
Latest Version Dependencies status unknown Test status unknown Test coverage unknown
Project Description

Introduction

This package is made from the xpermutations recipe submitted to ActiveState by Ulrich Hoffman.

The documentation provided therein follows and is assumed to be under the Creative Commons Attribution 3.0 license.

Install with pip or easy_install:

sudo pip install xpermutations

Recipe Documentation (Ulrich Hoffman)

Permutations and combinations are often required in algorithms that do a complete search of the solution space. They are typically rather large so it’s best not to compute them entirely but better to lazily generate them. This recipe uses Python 2.2 generators to create appropriate generator objects, that can be use for example as ranges in for loops.

This recipe provides both combinations and permutations and lazily generates them. You can do arbitrary calculations on the permutation/combination items not just print them.

If you require the complete list of permutations, just use the built-in list() operator. Note that the resulting list can be huge.

All x-generators defined here yield sequences with elements from the original sequence. Their difference is in which elements they take:

xpermutations() takes all elements from the sequence, order matters.

xcombinations() takes n distinct elements from the sequence, order matters.

xuniqueCombinations() takes n distinct elements from the sequence, order is irrelevant.

xselections() takes n elements (not necessarily distinct) from the sequence, order matters.

Note that ‘distinct’ means “different elements in the orginal sequence” and not “different value”, i.e.:

>>> list(xuniqueCombinations('aabb', 2))
[['a', 'a'], ['a', 'b'], ['a', 'b'], ['a', 'b'], ['a', 'b'], ['b', 'b']]

Compare the latter to:

>>> all_different = list(set('aabb'))
>>> list(xuniqueCombinations(all_different, 2))
[['a', 'b']]

If your sequence has only items with unique values, you won’t notice the difference (no pun intended).

Caveats

Set theoreticians may take issue with the nomenclature.

Examples

xcombinations()

>>> " ".join("".join(x) for x in xcombinations("1234", 2))
'12 13 14 21 23 24 31 32 34 41 42 43'

xuniqueCombinations()

>>> " ".join("".join(x) for x in xuniqueCombinations("1234", 2))
'12 13 14 23 24 34'

xselections()

>>> " ".join("".join(x) for x in xselections("1234", 2))
'11 12 13 14 21 22 23 24 31 32 33 34 41 42 43 44'

xpermutations()

>>> " ".join("".join(x) for x in xpermutations("123"))
'123 132 213 231 312 321'
Release History

Release History

1.0.1

This version

History Node

TODO: Figure out how to actually get changelog content.

Changelog content for this version goes here.

Donec et mollis dolor. Praesent et diam eget libero egestas mattis sit amet vitae augue. Nam tincidunt congue enim, ut porta lorem lacinia consectetur. Donec ut libero sed arcu vehicula ultricies a non tortor. Lorem ipsum dolor sit amet, consectetur adipiscing elit.

Show More

1.0.0

History Node

TODO: Figure out how to actually get changelog content.

Changelog content for this version goes here.

Donec et mollis dolor. Praesent et diam eget libero egestas mattis sit amet vitae augue. Nam tincidunt congue enim, ut porta lorem lacinia consectetur. Donec ut libero sed arcu vehicula ultricies a non tortor. Lorem ipsum dolor sit amet, consectetur adipiscing elit.

Show More

Download Files

Download Files

TODO: Brief introduction on what you do with files - including link to relevant help section.

File Name & Checksum SHA256 Checksum Help Version File Type Upload Date
xpermutations-1.0.1.tar.gz (4.8 kB) Copy SHA256 Checksum SHA256 Source Apr 15, 2014

Supported By

WebFaction WebFaction Technical Writing Elastic Elastic Search Pingdom Pingdom Monitoring Dyn Dyn DNS HPE HPE Development Sentry Sentry Error Logging CloudAMQP CloudAMQP RabbitMQ Heroku Heroku PaaS Kabu Creative Kabu Creative UX & Design Fastly Fastly CDN DigiCert DigiCert EV Certificate Rackspace Rackspace Cloud Servers DreamHost DreamHost Log Hosting