deeptrack.backend.pint_definition Module

Pint constants and units definition for DeepTrack2.

This module consolidates and extends the default definitions provided by Pint’s default_en.txt and constants_en.txt files. It defines physical constants, unit systems, and project-specific adjustments necessary for DeepTrack2.

Introduction

Pint is a Python library used for handling units and quantities. This module augments Pint’s default definitions by introducing project-specific constants and unit modifications, ensuring precise and flexible calculations in the context of DeepTrack2.

Sources

• Pint’s default unit definitions: default_en.txt

• Pint’s default constants definitions: constants_en.txt

Content Overview

1. Mathematical Constants: Includes key values like pi, Euler’s number, and

   the natural logarithm of 10.

2. Physical Constants: Covers fundamental constants like the speed of

   light, Planck constant, and Boltzmann constant.

3. Derived Constants: Defines values such as the fine-structure constant

   and classical electron radius.

4. Units: Provides base and derived units for length, mass, time, energy,

   etc., with precise conversion factors.

5. Prefixes and Aliases: Defines standard prefixes (e.g., milli-, kilo-,

   mega-) and unit aliases.

6. Unit Systems: Details systems including SI, MKS, CGS, Planck, and

   imperial units.

7. Contexts and Conversion: Context-specific definitions for

   domain-specific conversions.

Key Modifications

This module is derived from the default Pint files with the following changes:

1. Groups Removed: Unit group definitions (e.g., @group) have been

   excluded to avoid conflicts with pixel definitions.

2. Final Variables Added: Constants and variables required for

   project-specific contexts, such as pixel-related units.

Example

To create a unit registry with custom pixel-related units:

>>> from pint import UnitRegistry
>>> from .backend.pint_definition import pint_definitions

>>> units = UnitRegistry(pint_definitions.split("\n"))