sammyny wrote: > > > If someone could point me a correct working version of newton method for > finding roots and its usage, that would be helpful. >
You mentioned in your original post that you had no idea how to use nleqslv. nleqslv provides a Broyden and Newton method with several different global search strategies for "difficult" functions. Here it is an example using your function (which is not particulary difficult if you look at the plot): library(nleqslv) # starting value -2 nleqslv(-2,f) # starting value 8 nleqslv(8,f) # manual multistart for( x in seq(-3,8,1)) { z <- nleqslv(x,f); print(c(z$x,z$fvec))} These example all use the Broyden method. If you want the Newton method then you can do for( x in seq(-3,8,1)) { z <- nleqslv(x,f,method="Newton"); print(c(z$x,z$fvec))} /Berend -- View this message in context: http://r.789695.n4.nabble.com/newton-method-tp2306111p2306973.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.