Test data for GeographicLib

NOTE: It's not necessary to download these files to use GeographicLib.

GeodTest.dat.gz and GeodTest-short.dat.gz provide test data for geodesics. See

https://geographiclib.sourceforge.io/C++/doc/geodesic.html#testgeod

TMCoords.dat.gz provides test data for the transverse Mercator projection. See

https://geographiclib.sourceforge.io/C++/doc/transversemercator.html#testmerc

GeoidHeights.dat.gz provides test data for geoid heights. See

https://geographiclib.sourceforge.io/C++/doc/geoid.html#testgeoid

Geod3Test-v1.txt.gz provides test data for geodesics on a triaxial ellipsoid with semiaxes, [a, b, c] = [√2, 1, 1/√2]. This dataset is described in

https://doi.org/10.5281/zenodo.12510796

Geod3Test-*-v1.txt.gz provide corresponding test data for geodesics on biaxial ellipsoids. The coordinates for the endpoints match those in Geod3Test-v1.txt.gz and, note well, that these are triaxial ellipsoidal coordinates. The semiaxes of the ellipsoids are

• Geod3Test-obl-v1.txt.gz: oblate limit, [a, b, c] = [1, 1, 1/2]
• Geod3Test-pro-v1.txt.gz: prolate limit, [a, b, c] = [2, 1, 1]
• Geod3Test-sph*-v1.txt.gz: spherical limit, b = 1, a → b, and c → b, such that k² = (b² − c²)/(a² − c²) is given by
  • Geod3Test-spha-v1.txt.gz: k² = 1
  • Geod3Test-sphb-v1.txt.gz: k² = 2/3
  • Geod3Test-sphc-v1.txt.gz: k² = 1/3
  • Geod3Test-sphd-v1.txt.gz: k² = 0