The purpose of the software is to calculate the undulation between the WGS84 ellipsoid (GPS height) and the EGM96 geoid (mean sea level) in MATLAB, based on the C code in the "egm96-f477.c" project
C translation of EGM96 (earth height model) implementation (namely, f477.f) available at http://earth-info.nga.mil/GandG/wgs84/gravitymod/egm96/egm96.html