Background information


This is a tool that enables the user to apply a full Datum transformation between 2 geodetic reference systems (input, output).
One of the systems can be the global WGS84 reference for instance, and the other can be any Local Reference System defined on any user-defined ellipsoid.
The usual reference ellipsoids (Bessel, Clarke, Hayford (International), Airy, Everest etc.) are also provided.


The transformation method uses 7 parameters (and optionally the 3 geocentric coordinates of a local centroid or pivot point).
The method is known as Bursa-Wolf- ( cq Molodensky-Badekas-) transformation.


The user has to provide the following input:
The 3 shift components of the position vector (in meters),
The 3 rotations of the coordinate frame about the respective axes (in 10e-9 radians, 'nano-radians'),
The difference of scale (in 10e-9 m per meter),
Optionally the geocentric coordinates (with respect to the axes of the input ellipsoid) of a local centroid (origin of Reference System 1),
The ellipsoid parameters a and 1/f of the input system, and those of the output system (both provided in a combo box for many usual ellipsoids),
An input (terrain-) point P, given in latitude, longitude (decimal degrees) and height (m above the input ellipsoid),


Geocentric coordinates of P in the input system (Reference System 1),
Geocentric coordinates of P in the output system (Reference System 2),
Ellipsoidal latitude, longitude and height of P in the output system (again in decimal degrees and m respectively).

Numerical Example
Reference1 Reference2

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