> On 19 Oct 2016, at 14:09, Mike meyer <1101...@gmx.net> wrote: > > @pd: you know that a System of equations with more variables than equations > is always solvable > and if a unique solution is desired one of mimimal norm can be used. >
Not true. Take the system with 3 variables and 2 equations x+y+z = 3 x+y+z = 4 This does not have a solution. See https://en.wikipedia.org/wiki/Consistent_and_inconsistent_equations Berend > According to "Methods for nonlinear least squares problems" by Madsen, > Nielsen and Tingleff the LM-algorithm > solves Systems of the form > [J(x)'J(x)+\mu*I]x=... > with \mu>0 so that the Matrix on the left is always positive definite, > especially nonsingular. > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
