Eye4Software Hydromagic

Professional hydrographic survey software

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In geodesy, a reference ellipsoid is a mathematically-defined surface that approximates the geoid, the truer figure of the Earth, or other planetary body. Because of their relative simplicity, reference ellipsoids are used as a preferred surface on which geodetic network computations are performed and point coordinates such as latitude, longitude, and elevation are defined.

Configuring ellipsoids

An ellipsoid can be defined in Hydromagic using the following three parameters:

The eccentricity value is optional, because this value can be calculated using the semi major axis and the flattening using the following formula:

e2 = ( 2.0 * f ) - ( f * f )
Formula to calculate the eccentricity squared from the inverse flattening

List of ellipsoids supported by Hydromagic