Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
NCTM or The Math Forum.



Re: Least square fit of nonlinear equations
Posted:
May 7, 2011 10:26 PM


MarquardtLevenbergSpencerAnselmo steepest descent. Set the sum of all equations to zero Be careful for multiple roots. MatLab, Mathematica and their sourceforge.net free/open clones all have this. Spencer worked for Marquardt at duPont, Anselmo was Spencer's doctoral student at COlumbia. Fifteen years ago there were some issues with matlab nonlin I don't remember. A lot of econometric systems (rats, eviews, rlanguage) have nonline also. Most theoretical mathematicianc complain nonlin methods allow folks to develop models they don't really understand. As an undergrad (197981) I used to love the nonlin in (DEC20) Mlab (civilized.com) but neither I nor people I work with can really afford the current version.
 =  Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist http://www.panix.com/~vjp2/vasos.htm {Nothing herein constitutes advice. Everything fully disclaimed.} [Homeland Security means private firearms not lazy obstructive guards] [Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]



