This is a side effect of the lazy evaluation done in functions. Look at the help page for the force function for more details and how to force evaluation and solve your problem.
-- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.s...@imail.org 801.408.8111 > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- > project.org] On Behalf Of Eduardo de Oliveira Horta > Sent: Monday, November 15, 2010 1:50 PM > To: r-help@r-project.org > Subject: [R] Defining functions inside loops > > Hello, > > I was trying to define a set of functions inside a loop, with the loop > index > working as a parameter for each function. Below I post a simpler > example, as > to illustrate what I was intending: > > f<-list() > for (i in 1:10){ > f[[i]]<-function(t){ > f[[i]]<-t^2+i > } > } > rm(i) > > With that, I was expecting that f[[1]] would be a function defined by > t^2+1, > f[[2]] by t^2+2 and so on. However, the index i somehow doesn't "get > in" the > function definition on each loop, that is, the functions f[[1]] through > f[[10]] are all defined by t^2+i. Thus, if I remove the object i from > the > workspace, I get an error when evaluating these functions. Otherwise, > if > don't remove the object i, it ends the loop with value equal to 10 and > then > f[[1]](t)=f[[2]](t)=...=f[[10]](t)=t^2+10. > > I am aware that I could simply put > > f<-function(u,i){ > f<-t^2+i > } > > but that's really not what I want. > > Any help would be appreciated. Thanks in advance, > > Eduardo Horta > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. ______________________________________________ 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.
