Sorry, I made a mistake, I'm not used with Jacobian, the jacobian[i][2]= -1/x ... (without c parameter ...) and it should be ok using the common apache MultivariateMatrixFunction jacobian ... Eric.
Le 17 avr. 2013 à 07:52, Eric HENON a écrit : > Hello, > > I need to perform a non linear regression using this > function: y = a + b lnx -c/x (a,b,c) being the parameters. > I want to do this within the java language. > > I have a set of points (y1,x1), (y2, x2), … (yn, xn). > > > The least square solver available in commons apache seemed > to me a possible way to solve this, but it needs the jacobian matrix, > which in my case, depends on the "c" parameter itself … > > This, I don't know how to implement the MultiVariateMatrixFunction jacobian() > in this case. > > jacobian[i][0]= 1; > jacobian[i][1]= ln x; > jacobian[i][2]= ??? (+c/x^2) ?? > The problem is that the "c" parameter appears in the formula here... > > Any help will be appreciated. > Thanks in advance. > Eric > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: user-unsubscr...@commons.apache.org > For additional commands, e-mail: user-h...@commons.apache.org > Eric Henon Professeur Universite de Reims Champagne-Ardenne Institut de Chimie Moleculaire de Reims http://www.univ-reims.fr/ICMR CNRS UMR 6229 UFR des Sciences Exactes et Naturelles BP 1039 51687 Reims Cedex 2 (France) Tél./Fax : + 33 (0) 3 26 91 84 97 eric.he...@univ-reims.fr --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@commons.apache.org For additional commands, e-mail: user-h...@commons.apache.org
