Thank you Erik and Patrick, using vectorization and apply function seem to be very promising, even though I don't know how to use apply/sapply for updating discrete time difference equation instead of using for loop. (e.g, Nt+1 = Nt (1+R(K-Nt/K)))
Maybe I could use vector for different parameters, and for loop for updating the equation. Best, Nic On Sun, Jul 11, 2010 at 1:02 PM, Patrick Connolly < p_conno...@slingshot.co.nz> wrote: > On Fri, 09-Jul-2010 at 08:25AM -0700, S.Nicholas wrote: > > |> deaR useRs, > |> > |> I am trying to assign different values to different objects in a for > loop. > |> The following is a toy example of the part that has been giving me a > hard > |> time. > |> > |> The first "for loop" generates four objects, b0, b1, b2, b3 with random > |> numbers. > |> And, the second "for loop" is equivalent to > |> b1 = b0 > |> b2 = b1 > |> b3 = b2 > |> b4 = b3 > > I don't quite get the idea, but would you be able to simply reverse > the order of those last 4 (for i in 3:0)? That way, they won't all be > overwritten with b0. > > HTH > > > > |> > |> But, when I run this code, the result is equivalent to > |> b1 = b0 > |> b2 = b0 > |> b3 = b0 > |> b4 = b0 > |> > |> So, the increment does not seem to be properly working for the second > part > |> of the "assign" function. > |> Why would this be? > |> > |> for (i in 0:3) > |> { > |> r = runif(1) > |> assign(paste('b',i,sep=''),r) > |> } > |> > |> > |> for (i in 1:4) > |> { > |> > |> assign(paste('b',i,sep=''),eval(parse(text=paste('b',i-1,sep='')))) > |> } > |> > |> Thank you. > |> > |> Nic > |> > |> [[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. > > -- > ~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~. > ___ Patrick Connolly > {~._.~} Great minds discuss ideas > _( Y )_ Average minds discuss events > (:_~*~_:) Small minds discuss people > (_)-(_) ..... Eleanor Roosevelt > > ~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~. > [[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.