Please learn how to use `RsiteSearch' before posting questions to the list:
RSiteSearch("derivative smooth function") This should have provided you with plenty of solutions. Ravi. ____________________________________________________________________ Ravi Varadhan, Ph.D. Assistant Professor, Division of Geriatric Medicine and Gerontology School of Medicine Johns Hopkins University Ph. (410) 502-2619 email: rvarad...@jhmi.edu ----- Original Message ----- From: FMH <kagba2...@yahoo.com> Date: Friday, April 2, 2010 4:39 am Subject: [R] Derivative of a smooth function To: r-help@r-project.org Cc: r-sig-fina...@stat.math.ethz.ch > Dear All, > > I've been searching for appropriate codes to compute the rate of > change and the curvature of nonparametric regression model whish was > denoted by a smooth function but unfortunately don't manage to do it. > I presume that such characteristics from a smooth curve can be > determined by the first and second derivative operators. > > The following are the example of fitting a nonparametric regression > model via smoothing spline function from the Help file in R. > > ####################################################### > attach(cars) > plot(speed, dist, main = "data(cars) & smoothing splines") > cars.spl <- smooth.spline(speed, dist) > lines(cars.spl, col = "blue") > lines(smooth.spline(speed, dist, df=10), lty=2, col = "red") > legend(5,120,c(paste("default [C.V.] => df > =",round(cars.spl$df,1)),"s( * , df = 10)"), col = c("blue","red"), > lty = 1:2, bg='bisque') > detach() > > ####################################################### > > > Could someone please advice me the appropriate way to determine such > derivatives on the curves which were fitted by the function above and > would like to thank you in advance. > > Cheers > Fir > > > > > > ______________________________________________ > R-help@r-project.org mailing list > > PLEASE do read the posting guide > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org 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.