collections-extended 0.3.1

Extra Python Collections - bags (multisets) and setlists (ordered sets)

Documentation: http://collections-extended.lenzm.net/

GitHub: https://github.com/mlenzen/collections-extended

PyPI: https://pypi.python.org/pypi/collections-extended

Overview

This package includes one module - collections_extended. This module provides a bag class, AKA multiset, and a setlist class, which is a unique list or ordered set. There are also frozen (hashable) varieties of each included.

Tested against Python 2.6, 2.7, 3.2, 3.3, 3.4 & PyPy.

Getting Started

>>> from collections_extended import bag, setlist
>>> b = bag('abracadabra')
>>> b.count('a')
5
>>> b.remove('a')
>>> b.count('a')
4
>>> 'a' in b
True
>>> b.count('d')
1
>>> b.remove('d')
>>> b.count('d')
0
>>> 'd' in b
False

>>> sl = setlist('abracadabra')
>>> sl
setlist(('a', 'b', 'r', 'c', 'd'))
>>> sl[3]
'c'
>>> sl[-1]
'd'
>>> 'r' in sl  # testing for inclusion is fast
True
>>> sl.index('d')  # so is finding the index of an element
4
>>> sl.insert(1, 'd')  # inserting an element already in raises a ValueError
Traceback (most recent call last):
...
        raise ValueError
ValueError
>>> sl.index('d')
4

Installation

pip install collections-extended

Usage

from collections_extended import bag, frozenbag, setlist, frozensetlist

Classes

There are four new classes provided:

bags

bag

This is a bag AKA multiset.

frozenbag

This is a frozen (hashable) version of a bag.

setlists

setlist

An ordered set or a list of unique elements depending on how you look at it.

frozensetlist

This is a frozen (hashable) version of a setlist.

Collection Factory

A Collection factory is provided where you can specify whether you want the Collection returned to be mutable, have unique elements and/or be ordered. If an Iterable object is passed the Collection will be filled from it, otherwise it will be empty.

collection(it = None, mutable=True, unique=False, ordered=False)

Author:

Michael Lenzen

Copyright:

2015 Michael Lenzen

License:

Apache License, Version 2.0

Project Homepage:

https://github.com/mlenzen/collections-extended