I am trying to check if my Minerr solution to a nonlinear-regression, Levenberg-Marquardt curvefit of a circle to data points worked correctly. I did not get an error message, so I think the iterations converged. But I cannot check simply by the error at each data point, because, obviously, it is a minimization problem, so one expects to get error at each data point - it is a best curvefit problem. I set the TOL and CTOL convergence-error values to 1e-010, and I still got no error message. So I think it converged, but I want to make sure. If I could confirm that a non-trivial number of iterations was performed, then I could be somewhat reassured. But if it stopped after, say, 2 iterations, then I would guess that something got misinterpreted by Mathcad, perhaps in the required vectorization.
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