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Software development & validation for Geodetic Datum Transformations
The first and last steps are easily solved using the appropriate formulae
We are interested in solving steps 2 and 3, which is accomplished using this software. The method is as follows:
where 
Source of Information : Joó, I. et al., 1985; Ádám, J., 1987; Official communications (Ádám, J. and Borza, T.); Gubler, E. et al. (eds), 1992; Gubler, E. et al. (eds), 1993; (see Chapter 8). The software The software requires a Database of points with the coordinates known in both the reference systems. It then calculates the coordinates of the points required in the local coordinate system, given the coordinates of the point in the WGS 84 system. The points used for estimating the transformation parameters, which vary from region to region, for the point/points in question, are chosen by the program by calculating the distances of the point from all the points given in the database and then choosing all the points which are within a range of 20 Km. The program is user friendly and lets the user know if there are no points within a range of 20 Km. A minimum of 3 points has to be lie within the range, else the program won't proceed, since the method used is the "Least Square Adjustment". There are seven transformation parameters to be estimated. the principle used is least square adjustment. The utility of the software simply put, is because of the fact that one can't perform the complex and huge matrix operations without a computer. The matrix used can be of the order of 100*100 depending on the number of points in the vicinity of the point of interest. The program can take input interactively one after the other, or take input from some user defined file.in the applicable format |