pybelbg 26.7.29

Pure Python Belgian hBG18 and Lambert conversions

A pure Python implementation of the Belgian hybrid quasi-geoid hBG18 with several Belgian Lambert 2018, -1972 and -1950 conformal conic projections to convert between geodetic lat-, longitude and ellipsoidal height and local Lambert easting, northing and orthometric height using bilinear interpolation of quasi-geoid hBG18 heights.

Each of 5 Be*LBG transformer classes provides a forward method to convert a geodetic lat-, longitude and ellipsoidal height to local easting, northing and orthometric height (H) and a reverse method to transform local to geodetic coordinates and orthometric to ellipsoidal height.

Quasi-geoid hBG18 height is interpolated only for locations within the hBG18 region. Heights outside that region are NAN unless raising a BeLBGError exception is specified.

For further details see the documentation and the main module.

Installation

To install pybelbg, type python[3] -m pip install pybelbg or python[3] -m easy_install pybelbg in a terminal or command window.

Alternatively, download pybelbg-yy.m.d.tar.gz from PyPI or GitHub, unzip the downloaded file, cd to directory pybelbg-yy.m.d and type python[3] setup.py install.

To run the pybelbg tests, type python[3] test/run.py or type python[3] test/unitTestSuite.py before or after installation.

Dependencies

Installation of Python package pygeodesy is required, version 26.7.27 or newer. Type python[3] -m pip install -r requirements.txt to install.

Documentation

In addition to the pybelbg package, the pybelbg distribution file contain the tests, the test results (on macOS only) and the complete documentation generated by Epydoc using command line: epydoc --html --no-private --no-source --name=pybelbg --url=... -v pybelbg.

Tests

The tests ran with Python 3.14.6, 2.7.18 and with PyPy 7.3.17 (Python 3.10.14), all with pygeodesy 26.5.26 and on macOS 26.5.2 Tahoe in 64-bit. The results of those tests are included in the distribution file.

Python 3.14.6 and PyPy 7.3.17 run on Apple M4 (arm64), natively. Python 2.7.18 runs on Intel (x86_64) or Intel emulation ("arm64_x86_64", see function pybelbg.machine).

Test coverage has been measured with coverage 7.14.0 using Python 3.14.6. The complete coverage report in HTML and a PDF summary are included in the distribution file.

The tests also ran with Python 3.14.6 on Windows 2019Server and with Python 3.13.3 on Windows 11, both in 64-bit only.

Notes

All Python source code has been statically checked with Ruff using Python 3.13.12 and with PyChecker, PyFlakes, PyCodeStyle (formerly Pep8) and McCabe using Python 2.7.18, both in 64-bit on macOS 26.5.2 Tahoe only.

Last updated: July 29, 2026.

License

Copyright (C) 2026-2026 -- mrJean1 at Gmail -- All Rights Reserved.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.