unyt: Handle, manipulate, and convert data with units in Python

TL;DR

unyt is a Python library that simplifies handling, manipulating, and converting data with units, aiming to reduce errors and improve performance compared to existing solutions.

Contribution

The paper introduces unyt, a new Python library for unit management that is faster, more tested, and more concise than comparable libraries like Pint and astropy.units.

Findings

unyt outperforms Pint and astropy.units in speed.

unyt has higher test coverage.

unyt has fewer lines of code.

Abstract

Software that processes real-world data or that models a physical system must have some way of managing units. While simple approaches like the understood convention that all data are in a unit system (such as the MKS SI unit system) do work in practice, they are fraught with possible sources of error both by developers and users of the software. In this paper we present unyt, a Python library based on NumPy and SymPy for handling data that has units. It is designed both to aid quick interactive calculations and to be tightly integrated into a larger Python application or library. We compare unyt with two other Python libraries for handling units, Pint and astropy.units, and find that unyt is faster, has higher test coverage, and has fewer lines of code.