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Unit: SDL_geobasics
Class: none
Declaration: [1] function GeoEllEccSquared (Ellipsoid: TGeoEllipsoid): double;
[2] function GeoEllEccSquared (SemiMajorAx, SemiMinorAx: double): double;
[3] function GeoEllEccSquared (RecipFlattening: double): double;

The function GeoEllEccSquared calculates the squared eccentricity e2 of an ellipsoid:

e2 = 1 - b2/a2

with a = semimajor axis, and b = semiminor axis.

Version [1] calculates it from the ellipsoid given by the parameter Ellipsoid, version [2] calculates the eccentricity from the lengths of the semimajor and semiminor axes (parameters SemiMajorAx and SemiMinorAx), and version [3] calculates it from the reciprocal flattening.

Hint: An infinite reciprocal flattening passed to the function in the parameter RecipFlattening has to be indicated by setting RecipFlattening to a zero value.

Last Update: 2012-Okt-20