From: Rolf Turner > > On 8/09/2009, at 9:07 PM, FMH wrote: > > > Dear All, > > > > I'm looking for a way on computing the derivative of first and > > second order of a smoothing curve produced by a nonprametric > > regression. For instance, if we run the R script below, a smooth > > nonparametric regression curve is produced. > > > > provide.data(trawl) > > Zone92 <- (Year == 0 & Zone == 1) > > Position <- cbind(Longitude - 143, Latitude) > > dimnames(Position)[[2]][1] <- "Longitude - 143" > > sm.regression(Longitude, Score1, method = "aicc", col = "red", > > model = "linear") > > > > Could someone please give some hints on the way to find the > > derivative on the curve at some points ? > > See > > ?smooth.spline > and > ?predict.smooth.spline
Since sm.regression() (from the sm package, I presume) uses kernel methods, a kernel-based estimator of derivatives is available in the KernSmooth package. Andy > cheers, > > Rolf Turner > > ###################################################################### > Attention:\ This e-mail message is privileged and > confid...{{dropped:9}} > > ______________________________________________ > 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. > Notice: This e-mail message, together with any attachme...{{dropped:12}} ______________________________________________ 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.