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3D coordinate transformation

Open zsiki opened this issue 5 years ago • 2 comments

for 3D coordinate transformation use tcllib::math module. ::math::linearalgebra::determineSVD

zsiki avatar Apr 08 '19 17:04 zsiki

Revise reggeo.tcl to use tcllib where possible and Jacobi proc and GaussElimination proc.

zsiki avatar Apr 08 '19 18:04 zsiki

Hi @zsiki .

SVD is optional. A completely sane solution is obtained with the simplest normalization of variables (Xn = X - M(X)). For a detailed solution with Gaussian normalization (Xg = (X - M(X)) * sG; sG = 1 / sqrt(Tr(D(X)))) see https://github.com/Geo-Linux-Calculations/geodesy-msexcel-ols/blob/main/spreadsheets/conformaltrans/helmert3d.xls . The condition number (cond(G)) in this case turns out to be quite sane (in the example it is equal 38) and such a matrix can be solved by the usual LL decomposition.

zvezdochiot avatar Jul 06 '22 23:07 zvezdochiot