search for: nlregb

...veryone, I'm interested in the analysis of spatial data, and I'm trying out several R-packages. Today I was attempting to use the package vardiag (version 0.1): >> library(vardiag) >> rs4.vo <- varobj(rs4[,2:4],trace=2) >[1] 1 >Error: couldn't find function "nlregb" so far I know "nlregb" is a S-plus function for optimization, so this can not work in R, other? How could one create or import an appropiate "variogram object" to use the other functions in this package, for example if I estimate the empirical variogram using geoR? than...

Hi, I've been using "nlregb" routine in splus3.4, but cannot find it here in R. Is it hidden in some library? Or there is a routine equivalent to it but with a different name? I'm planning to move part of my from S to R so that I can work comfortablely at home. Any suggestion is highly appreciated. regards, Tony --...

I would like to fit a model of the type Y = Xf + e where f are cover fractions (or percent cover). Therefore, I must constrain the fit to 1. sum(f) = 1 2. 0<= f <=1 How can I introduce these 2 constraints in a ML fit? Currently, I'm using nlregb and I'm using the "upper and low" keywords to set the bounds and use the following to ensure that sum(f) = 1: let's say I have 3 fractions, then f3=1-f1-f2 and Y = f1*X1 + f2*X2 +(1-f1-f2)*X3 Y - X3 = f1(X1-X3) + f2*(x2-X3) so I minimize (considering Z <- X[,1:2] - X[,3]) Y...

...in nlsModel(formula, mf, start) : singular gradient matrix at initial parameter estimates while I get no error without setting the control option with the same other parameters. I see that R didn't manage to solve the Eckerle4 regression problem from start one while Splus can do it with the nlregb option. Is there something equivalent for R now? Otherwise, I found that R 2.0.1 was performing better than SAS 9.1 on the NIST Datasets in general. Best regards, Anthony Landrevie --------------------------------- [[alternative HTML version deleted]]