.. image:: https://img.shields.io/pypi/v/pint.svg :target: https://pypi.python.org/pypi/pint :alt: Latest Version .. image:: https://img.shields.io/badge/code%20style-black-000000.svg :target: https://github.com/python/black .. image:: https://readthedocs.org/projects/pint/badge/ :target: https://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://github.com/hgrecco/pint/workflows/CI/badge.svg :target: https://github.com/hgrecco/pint/actions?query=workflow%3ACI :alt: CI .. image:: https://github.com/hgrecco/pint/workflows/Lint/badge.svg :target: https://github.com/hgrecco/pint/actions?query=workflow%3ALint :alt: LINTER .. image:: https://coveralls.io/repos/github/hgrecco/pint/badge.svg?branch=master :target: https://coveralls.io/github/hgrecco/pint?branch=master :alt: Coverage 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 3.9+ 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 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 >>> np.sum(_) 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/ Command-line converter ---------------------- A command-line script `pint-convert` provides a quick way to convert between units or get conversion factors. 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 programmed 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 a text file which is simple and easy to edit. 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 symbolic, LaTeX and pretty formatting. Unit name translation is available if Babel_ is installed. **Free to choose the numerical type**: You can use any numerical type (`fraction`, `float`, `decimal`, `numpy.ndarray`, etc). NumPy_ is not required but supported. **Awesome NumPy integration**: When you choose to use a NumPy_ ndarray, its methods and ufuncs are supported including automatic conversion of units. For example `numpy.arccos(q)` will require a dimensionless `q` and the units of the output quantity will be radian. **Uncertainties integration**: transparently handles calculations with quantities with uncertainties (like 3.14±0.01 meter) via the `uncertainties package`_. **Handle temperature**: conversion between units with different reference points, like positions on a map or absolute temperature scales. **Dependency free**: it depends only on Python and its standard library. It interacts with other packages like numpy and uncertainties if they are installed **Pandas integration**: Thanks to `Pandas Extension Types`_ it is now possible to use Pint with Pandas. Operations on DataFrames and between columns are units aware, providing even more convenience for users of Pandas DataFrames. For full details, see the `pint-pandas Jupyter notebook`_. Pint is maintained by a community of scientists, programmers and enthusiasts around the world. See AUTHORS_ for a complete list. To review an ordered list of notable changes for each version of a project, see CHANGES_ .. _Website: http://www.dimensionalanalysis.org/ .. _`comprehensive list of physical units, prefixes and constants`: https://github.com/hgrecco/pint/blob/master/pint/default_en.txt .. _`uncertainties package`: https://pythonhosted.org/uncertainties/ .. _`NumPy`: http://www.numpy.org/ .. _`PEP 3101`: https://www.python.org/dev/peps/pep-3101/ .. _`Babel`: http://babel.pocoo.org/ .. _`Pandas Extension Types`: https://pandas.pydata.org/pandas-docs/stable/development/extending.html#extension-types .. _`pint-pandas Jupyter notebook`: https://github.com/hgrecco/pint-pandas/blob/master/notebooks/pint-pandas.ipynb .. _`AUTHORS`: https://github.com/hgrecco/pint/blob/master/AUTHORS .. _`CHANGES`: https://github.com/hgrecco/pint/blob/master/CHANGES