The advances in surveying equipments was not followed by a development in the calculations processes in the same scale. Classical adjustment methods are still used, sometimes encapsuled in commercial softwares.
The error-minimizing approach by the least squares method is not a new techinique in surveying computations, but include some numerical difficulties hidden in the specialized bibliography.
This formulation forms the base of a surveying kernel software, named PZEllips, which intends to improve accuracy and efficiency in the computation process.
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