The neat thing about R is that it's interpreted, so you can look for yourself.
On Sat, Jul 9, 2011 at 3:46 PM, Bazman76 <h_a_patie...@hotmail.com> wrote: > m0<-epxression((4*theta1*theta2-theta3^2)/(2*x*theta3^2)-0.5*theta1*x) > > params<-all.vars(m0) this reads all the params > from m0 so theta1,2 and 3 correct? > m0<-expression((4*theta1*theta2-theta3^2)/(2*x*theta3^2)-0.5*theta1*x) > params<-all.vars(m0) > params [1] "theta1" "theta2" "theta3" "x" So no, not just the thetas but also x > params<-params[-which(params=="x")] checks which params are multiplied > by x? > params<-params[-which(params=="x")] > params [1] "theta1" "theta2" "theta3" Nope, see that it takes out the params that are not equal to x. You could look at, for instance ?which to figure that out, and also ?"==" > np<-length(params) > > for(i in 1:6){ > esp<-get(sprintf("m%d",i-1)) what does get do? sprinf > formats strings? so what is it doinf here? Again, you can try it. > i <- 1 > sprintf("m%d",i-1) [1] "m0" So it's taking the value of i, and combining it with some other things to make a character name. get() will get the R object with that name and assign it to esp ?get will tell you that. > assign(sprintf("m%d",i),D(esp,"x")) what doeas assign so what in > sprintf doing and what does D do? > } Same thing in reverse. I'll leave this one as an exercise for the querent. Sarah > really really confused? Learning to try things and to read the help are the only cure. Sarah -- Sarah Goslee http://www.functionaldiversity.org ______________________________________________ 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.