Thanks for the quick replies. I'll see if I can get that to work and let you know.
On Sun, Jul 3, 2011 at 10:54 AM, Luc Maisonobe [via Apache Commons] < [email protected]> wrote: > Le 03/07/2011 14:47, jeesh a écrit : > > Hi everyone, > > Hi Jeesh, > > > I'm somewhat new to java, but I'm looking to build a least squares > > optimization routine for a 2D Gaussian Fit based on this link (about half > > > way down) http://commons.apache.org/math/userguide/optimization.html. > > > > Just a general question - how would I go about structuring the Jacobian > > matrix for a two component function? > > You can organize the rows as you want. In the quadratic example of the > user guide page you cite, the rows correspond to simply to different > measurement points. For simplicity, they have been put in x increasing > order, but they could have been put in any order. So in your case, you > could choose something like: > > index 0 : (x0, y0) > index 1 : (x0, y1) > index 2 : (x0, y2) > ... > index n-1: (x0, yn-1) > index n : (x1, y0) > index n+1: (x1, y1) > ... > > or the other way round: > > index 0 : (x0, y0) > index 1 : (x1, y0) > index 2 : (x2, y0) > ... > index m-1: (xm-1, y0) > index m : (x0, y1) > index m+1: (x1, y1) > ... > > or even a random order, and your (xi,yj) samples may even not be > regularly spaced but could be random points. > > Once you have chose some ordering, you should use the same order for the > rows of the jacobian matrix and the values of the function as returned > by the respectively the jacobian method and the value method of your > DifferentiableMultivariateVectorialFunction implementation. The same > order should also be used for the target array you pass to the optimize > method of the optimizer. > > best regards, > Luc > > > > > Any help would be appreciated. > > > > -- > > View this message in context: > http://apache-commons.680414.n4.nabble.com/Math-Jacobian-Matrix-of-f-x-y-tp3641890p3641890.html > > Sent from the Commons - User mailing list archive at Nabble.com. > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [hidden > > email]<http://user/SendEmail.jtp?type=node&node=3642029&i=0> > > For additional commands, e-mail: [hidden > > email]<http://user/SendEmail.jtp?type=node&node=3642029&i=1> > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [hidden > email]<http://user/SendEmail.jtp?type=node&node=3642029&i=2> > For additional commands, e-mail: [hidden > email]<http://user/SendEmail.jtp?type=node&node=3642029&i=3> > > > > ------------------------------ > If you reply to this email, your message will be added to the discussion > below: > > http://apache-commons.680414.n4.nabble.com/Math-Jacobian-Matrix-of-f-x-y-tp3641890p3642029.html > To unsubscribe from [Math] Jacobian Matrix of f(x,y), click > here<http://apache-commons.680414.n4.nabble.com/template/NamlServlet.jtp?macro=unsubscribe_by_code&node=3641890&code=bWljaGFlbHdvbmc4NjY4QGdtYWlsLmNvbXwzNjQxODkwfDIxMTA1MTgzODc=>. > > -- Michael Wong -- View this message in context: http://apache-commons.680414.n4.nabble.com/Math-Jacobian-Matrix-of-f-x-y-tp3641890p3642470.html Sent from the Commons - User mailing list archive at Nabble.com.
