set seed for random draws
I think it's easier than you are making it: the random seed is created in a "pretty-random" way when you first use it and then it is updated with each call to rDIST(). For example, set.seed(1) x1 <- .Random.seed rnorm(1) x2 <- .Random.seed rnorm(1) x3 <- .Random.seed identical(x1, x2) FALSE identical(x1, x3) FALSE identical(x2, x3) FALSE set.seed(1) identical(x1, .Random.seed) TRUE rnorm(2) identical(x3, .Random.seed) TRUE But the period for the random seed to repeat is very, very long so you don't have to think about it unless you really need to (or for reproducible simulations) Michael On Sat, Nov 5, 2011 at 7:22 PM, Md Desa, Zairul Nor Deana Binti
<zndeana at ku.edu> wrote:
Thank you everybody for the helpful advices. Basically, I try to figure out why I get different numbers as there are more than one seed for a loop within a loop. Well, I guest I got it now. Because every time random seed is called or specified it'll output different random numbers, as it's requested. Thanks! D
________________________________________ From: r-help-bounces at r-project.org [r-help-bounces at r-project.org] on behalf of Rolf Turner [rolf.turner at xtra.co.nz] Sent: Saturday, November 05, 2011 3:22 PM To: Patrick Burns Cc: r-help at r-project.org; Achim.Zeileis at uibk.ac.at Subject: Re: [R] set seed for random draws On 05/11/11 22:00, Patrick Burns wrote: <SNIP> I'd suggest two rules of thumb when coming up against something in R that you aren't sure about: 1. If it is a mundane task, R probably takes care of it. 2. Experiment to see what happens. Of course you could read documentation, but no one does that. <SNIP> Fortune nomination! ? ? cheers, ? ? ? ? Rolf ______________________________________________ R-help at 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 at 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.