Dear all, I hope that this question is not too weird, I will try to explain it as good as I can. I have to write a function for a school project and one limitation is that I may not use the in built function sample() At one point in the function I would like to resample/rearrange the items of my sample (so I would want to use sample, but I am not allowed to do so), so I have to come up with sth else that does the same as the in built function sample() The only thing that sample() does is rearranging the items of a sample, so I searched the internet for a function that does that to be able to use it, but I cannot find anything that could help me. Can maybe someone help me with this? I would be very grateful, Cheers, Maria -- View this message in context: http://r.789695.n4.nabble.com/rearrange-set-of-items-randomly-tp4013723p4013723.html Sent from the R help mailing list archive at Nabble.com.
On Nov 7, 2011, at 4:09 PM, flokke wrote:> Dear all, > I hope that this question is not too weird, I will try to explain it > as good > as I can. > > I have to write a function for a school project and one limitation > is that I > may not use the in built function sample() > > At one point in the function I would like to resample/rearrange the > items of > my sample (so I would want to use sample, but I am not allowed to do > so), so > I have to come up with sth else that does the same as the in built > function > sample() > > The only thing that sample() does is rearranging the items of a > sample, so I > searched the internet for a function that does that to be able to > use it, > but I cannot find anything that could help me. > > Can maybe someone help me with this? > I would be very grateful,May I suggests thinking about the ordering of random variables? -- David Winsemius, MD West Hartford, CT
Sorry, but I dont think that I get what you mean (I am a quite new user though) I hae a data file of a sample, so I cannot use random numbers, the only thing I want to do is to randomly reassign the order of the items. -- View this message in context: http://r.789695.n4.nabble.com/rearrange-set-of-items-randomly-tp4013723p4015161.html Sent from the R help mailing list archive at Nabble.com.
On Nov 8, 2011, at 11:31 AM, flokke wrote:> Thanks for the replies! > > Indeed, I could use order() instead of sample() but that it wouldnt > be > random anymore, as it sorts data points in increasing(!) order. > Second, I > have to use 1000 different samples.Please re-read the help page for `order` _and_ the one for `sort`, examine their differences, re-read the replies you have gotten so far, work through _all_ of the examples, and if illumination still does not arrive, then repeat the above process until it does.> > I got the hint that I have to do somethin with indeces, but still cant > figure out what this should be. > Maybe someone of you knows?Many (if not most) of us do. We try to avoid having r-help becoming a homework tutoring site, however. You should be using your academic resources for this effort. -- David Winsemius, MD West Hartford, CT
If you don't want to go with the simple method mentioned by David and Ted, or you just want some more theory, you can check out: http://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle and implement that. -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare greg.snow at imail.org 801.408.8111> -----Original Message----- > From: r-help-bounces at r-project.org [mailto:r-help-bounces at r- > project.org] On Behalf Of flokke > Sent: Monday, November 07, 2011 2:09 PM > To: r-help at r-project.org > Subject: [R] rearrange set of items randomly > > Dear all, > I hope that this question is not too weird, I will try to explain it as > good > as I can. > > I have to write a function for a school project and one limitation is > that I > may not use the in built function sample() > > At one point in the function I would like to resample/rearrange the > items of > my sample (so I would want to use sample, but I am not allowed to do > so), so > I have to come up with sth else that does the same as the in built > function > sample() > > The only thing that sample() does is rearranging the items of a sample, > so I > searched the internet for a function that does that to be able to use > it, > but I cannot find anything that could help me. > > Can maybe someone help me with this? > I would be very grateful, > > Cheers, > Maria > > -- > View this message in context: http://r.789695.n4.nabble.com/rearrange- > set-of-items-randomly-tp4013723p4013723.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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.