===========
 intbitset
===========

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        :target: https://github.com/inveniosoftware-contrib/intbitset/releases

.. image:: https://img.shields.io/pypi/dm/intbitset.svg
        :target: https://pypi.python.org/pypi/intbitset

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        :target: https://github.com/inveniosoftware-contrib/intbitset/blob/master/LICENSE


Installation
============

intbitset is on PyPI ::

    pip install intbitset

We provide pre-built wheels for the most common operating systems and common 64 bits CPU
architectures. Otherwise, you will need a C compiler if you build from sources.


Documentation
=============

The ``intbitset`` library provides a set implementation to store sorted
unsigned integers either 32-bits integers (between ``0`` and
``2**31 - 1`` or ``intbitset.__maxelem__``) or an infinite range
with fast set operations implemented via bit vectors in a *Python C
extension* for speed and reduced memory usage.

The ``inbitset`` class emulates the Python built-in set class interface
with some additional specific methods such as its own fast dump and load
marshalling functions.  ::

    >>> from intbitset import intbitset
    >>> x = intbitset([1,2,3])
    >>> y = intbitset([3,4,5])
    >>> x & y
    intbitset([3])
    >>> x | y
    intbitset([1, 2, 3, 4, 5])

Additionally, ``intbitset`` supports:

- The `pickle protocol <https://docs.python.org/3/library/pickle.html>`_,
- The `iterator protocol <https://docs.python.org/3/library/stdtypes.html#iterator-types>`_
- ``intbitset`` can behave like a ``sequence`` that can be sliced.
- Natural min and max. Because the integers are always stored sorted, the fist
  element of a non-empty set `[0]` is also the `min()` integer and the last
  element `[-1]` is also the `max()` integer in the set.

When compared to the standard library ``set`` class, ``intbitset`` set
operations and the intersection, union and difference of ``intbitset``can be up
to 5000 faster for dense integer sets than the standard library ``set``.

Complete documentation is available at <http://intbitset.readthedocs.io> or
can be built using Sphinx: ::

    pip install sphinx
    python setup.py build_sphinx


Testing
=======

Running the tests are as simple as: ::

    pip install -e .[tests]
    pytest

Running the tests on multiple Python versions: ::

    pip install tox
    tox


Development
===========

To regenerate the C code with Cython: ::

    pip install cython
    cython intbitset/intbitset.pyx

Then commit the regenrated C source and update the CHANGELOG.rst


License
=======

Copyright (C) CERN and others

SPDX-License-Identifier: LGPL-3.0-or-later

intbitset is free software; you can redistribute it and/or modify it under the
terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 3 of the License, or (at your option) any later
version.

intbitset is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
intbitset; if not, write to the Free Software Foundation, Inc., 51 Franklin
Street, Fifth Floor, Boston, MA 02110, USA.

In applying this licence, CERN does not waive the privileges and immunities
granted to it by virtue of its status as an Intergovernmental Organization or
submit itself to any jurisdiction.
