Hi @Serrof,
True, maybe line 306 of Hipparchus SequentialGaussNewton:
// iterate until convergence is reached
Evaluation current = null;
Should be replaced by:
Evaluation current = oldEvaluation
To be discussed with @bcazabonne I’d say.
I still think it would be simpler for you to get the last estimations with your own Python version of a ResidualsHandler.java (3.8 KB)