JAG3D (Java Applied Geodesy 3D) is one of the most popular open source least-squares software package for geodetic sciences. The Java-based application is distributed under the terms of the GNU General Public License (version 3). JAG3D is designed to combine hybrid terrestrial observations like leveling, directions, distances or vertical angles in a uniform and rigorous mathematical model. Moreover, GNSS baselines that are derived by Global Navigation Satellite System (GNSS) techniques are supported. Some reference projects are the deformation analysis at the Onsala Space Observatory, or the adjustment of laser tracker measurements at the electron accelerator S-DALINAC. More information about the least-squares software package JAG3D can be found at software.applied-geodesy.org.
JAG3D is written in the platform-independent programming language Java and, therefore, the software is runnable at each platform and operation system that provides a Java Runtime Environment (JRE) and the JavaFX. JavaFX is included to the provided bundles. Moreover, the windows download package of JAG3D contains OpenJDK. For that reason, neither Java nor the platform dependent FX extension must be provided by the windows operating system. To run JAG3D on other platforms such as Linux or MacOS, the platform dependent JRE must be installed at the operating system. The JRE can be found for several platforms at Oracles download page or at the OpenJDK-project pages.
JAG3D is a portable least-squares software package - no need to install or uninstall. Just download the latest version, unpack and run. The JAG3D manual is organized by a Wiki. Training videos are compiled in a playlist. Moreover, a support forum is available for technical support.
Colleagues from Conservatoire National des Arts et Métiers (CNAM), European Organization for Nuclear Research (CERN), and School of Management and Engineering Vaud (HEIG-VD) evaluated the compatibility among network adjustment software packages. A detailed description of the procedure is published in Journal of Surveying Engineering, cf. DOI: 10.1061/(ASCE)SU.1943-5428.0000304. The authors compare the results of 17 networks using software packages developed by the authors' institutions, namely Compensation de Mesures Topographiques (CoMeT), Logiciel Général de Compensation (LGC), and Trinet+. The networks differ mainly in their extent. Whereas the smallest network is about 30 m, the largest network under consideration is about 40 km.
Moreover, the authors kindly ask developers of least-squares adjustment applications to readjust these 17 networks and to provide the adjustment results. Up to now, the adjustment results of eight different software packages are available. A short summery of the individual characteristics of the used software packages as well as an interactive graphic of the results can be found on the official CNAM website.
It is a very important initiative to ensure the quality of adjustment packages. For that reason, the results obtained by JAG3D are available. The largest network extent is about 40 km, and the curvature of the Earth can no longer be neglected. The results obtained by JAG3D differ by about 20 µm for the horizontal and the vertical component w.r.t. the designed values. JAG3D offers comparable results to reputable software packages.