On Sun, Aug 12, 2007 at 10:50:59AM -0700, Yuchen Luo wrote: > Dear Professor Murdoch. > Thank you so much!!!! > > Best Wishes > Yuchen Luo > > On 8/12/07, Duncan Murdoch <[EMAIL PROTECTED]> wrote: > > > > Yuchen Luo wrote: > > > Dear Colleagues. > > > > > > I believe this should be a problem encountered by many: > > > > > > nls( ) is a very useful and efficient function to use if we are just to > > > display the estimated value on screen. What if we need R to store the > > > estimated parameter in a variable? > > > > > > For example: > > > > > > x=rnorm(10, mean=1000, sd=10) > > > > > > y=x^2+100+rnorm(10) > > > > > > a=nls(y~(x^2+para),control=list(maxiter = 1000, minFactor=0.5 > > > ^1024),start=list(para=0.0)) > > > > > > How to store the estimated value of para in this case, in a variable, > > say, > > > b? > > > > > > It is easy to display a and find all the information. How ever, I need > > to > > > fit a different set of x and y in every loop of my code and I need to > > store > > > the estimated values for further use. I have checked both the online > > manual > > > and several S-plus books but no example as such showed up. > > > > > > Your help will be highly appreciated! > > > > coef(a) will get what you want. coef() works for most modelling > > functions where it makes sense. > > > > Duncan Murdoch > > >
further information might be extracted from the `summary' return value. e.g., if you need not only the parameters but also their error estimates, you could get them via summary(a)$parameters[, "Std. Error"] (question: is this the canonical way to do it or is their a better one?) ______________________________________________ R-help@stat.math.ethz.ch mailing list 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.
