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.. image:: https://img.shields.io/pypi/v/pint.svg
:target: https://pypi.python.org/pypi/pint
:alt: Latest Version
.. image:: https://readthedocs.org/projects/pip/badge/
:target: http://pint.readthedocs.org/
:alt: Documentation
.. image:: https://img.shields.io/pypi/l/pint.svg
:target: https://pypi.python.org/pypi/pint
:alt: License
.. image:: https://img.shields.io/pypi/pyversions/pint.svg
:target: https://pypi.python.org/pypi/pint
:alt: Python Versions
.. image:: https://travis-ci.org/hgrecco/pint.svg?branch=master
:target: https://travis-ci.org/hgrecco/pint
:alt: CI
.. image:: https://coveralls.io/repos/github/hgrecco/pint/badge.svg?branch=master
:target: https://coveralls.io/github/hgrecco/pint?branch=master
:alt: Coverage
.. image:: https://readthedocs.org/projects/pint/badge/
:target: http://pint.readthedocs.org/
:alt: Docs
Pint: makes units easy
======================
Pint is a Python package to define, operate and manipulate physical
quantities: the product of a numerical value and a unit of measurement.
It allows arithmetic operations between them and conversions from and
to different units.
It is distributed with a comprehensive list of physical units, prefixes
and constants. Due to its modular design, you can extend (or even rewrite!)
the complete list without changing the source code. It supports a lot of
numpy mathematical operations **without monkey patching or wrapping numpy**.
It has a complete test coverage. It runs in Python 2.7 and 3.3+
with no other dependency. It is licensed under BSD.
It is extremely easy and natural to use:
.. code-block:: python
>>> import pint
>>> ureg = pint.UnitRegistry()
>>> 3 * ureg.meter + 4 * ureg.cm
<Quantity(3.04, 'meter')>
and you can make good use of numpy if you want:
.. code-block:: python
>>> import numpy as np
>>> [3, 4] * ureg.meter + [4, 3] * ureg.cm
<Quantity([ 3.04 4.03], 'meter')>
>>> np.sum(_)
<Quantity(7.07, 'meter')>
Quick Installation
------------------
To install Pint, simply:
.. code-block:: bash
$ pip install pint
or utilizing conda, with the conda-forge channel:
.. code-block:: bash
$ conda install -c conda-forge pint
and then simply enjoy it!
Documentation
-------------
Full documentation is available at http://pint.readthedocs.org/
Design principles
-----------------
Although there are already a few very good Python packages to handle physical
quantities, no one was really fitting my needs. Like most developers, I programed
Pint to scratch my own itches.
- Unit parsing: prefixed and pluralized forms of units are recognized without
explicitly defining them. In other words: as the prefix *kilo* and the unit *meter*
are defined, Pint understands *kilometers*. This results in a much shorter and
maintainable unit definition list as compared to other packages.
- Standalone unit definitions: units definitions are loaded from simple and
easy to edit text file. Adding and changing units and their definitions does
not involve changing the code.
- Advanced string formatting: a quantity can be formatted into string using
PEP 3101 syntax. Extended conversion flags are given to provide latex and pretty
formatting.
- Small codebase: small and easy to maintain with a flat hierarchy.
- Dependency free: it depends only on Python and its standard library.
- Python 2 and 3: A single codebase that runs unchanged in Python 2.7 and Python 3.3+.
- Advanced NumPy support: While NumPy is not a requirement for Pint,
when available ndarray methods and ufuncs can be used in Quantity objects.
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