Possibly not the absolutely most efficient answer, but this is probably an answer nonetheless (David, hope I'm not encouraging bad behavior by replying.)
isp <- data.frame(begin=c(1,5,6,15,31,51,102), end=c(7,9,13,21,49,52,109)) isp ints = apply(isp, 1, function(x)seq(x[1],x[2])) ints ints = do.call(c, ints) ints ## option to fix if the regions are overlapping ## and you don't want overlapping regions resampled ints = unique(ints) ## sample from ints sample(ints, 5) sample(ints, 5, replace=TRUE) On Wed, Dec 7, 2011 at 10:20 AM, Mao Jianfeng <jianfeng....@gmail.com>wrote: > Dear David, > > Thanks for your response and warnings. > > I will obey the rule and be a good citizen. > > Best, > Jian-Feng, > > > Because you have a poorly posted problem. As far as I can tell you have not > yet responded constructively to the attempts at clarification of the > problem. Cross-posting to this list after waiting only 4 hours with an > identical problem is bad Rhelp behavior. You should use the interactive > facilities at SO and better respect the efforts already being extended on > your behalf. > > > > > > > > > > > >> I expect to hearing your helps/advice/directions in email or response in > >> stackoverflow webpage. Thanks a lot in advance. > >> > >> Best wishes, > >> > >> Jian-Feng, > >> > >> > >> I describe my question using the following dummy. > >> > >> ############################## > >> > >> # (1) the data (integer space consist of integer intervals defined by > >> their > >> begin and end) I have, > >> > >> integer.space <- data.frame(begin=c(1,5,6,15,**31,51,102), > >> end=c(7,9,13,21,49,52,109)) > >> > >> > >> ##############################**####### > >> > >> # (2) what I want is to select the consequent integer intervals with > >> # intra-length of 3 and inter-length of 2. and output the selected > >> # intervals as begin and end. In this selection, I would like to select > >> # more integer intervals as most as it could be. > >> # the following are intervals I expected to be selected from the dummy > >> data > >> > >> begin,end > >> 1,3 > >> 6,8 > >> 11,13 > >> 16,18 > >> 31,33 > >> 36,38 > >> 41,43 > >> 46,48 > >> 102,105 > >> > > > > Last item does NOT have length of 3. Why have you not responded to this > > observation on SO? And why would there not also be another line in the > > sequence after 102,104 that would be 106,108? My suggestion would be to > go > > back to SO and be a better citizen. > > > > > >> [[alternative HTML version deleted]] > >> > > > > Posting in HTML is also bad citizenship on R-help. > > > > > >> ______________________________**________________ > >> R-help@r-project.org mailing list > >> https://stat.ethz.ch/mailman/**listinfo/r-help< > https://stat.ethz.ch/mailman/listinfo/r-help> > >> PLEASE do read the posting guide http://www.R-project.org/** > >> posting-guide.html <http://www.R-project.org/posting-guide.html> > >> and provide commented, minimal, self-contained, reproducible code. > >> > > > > David Winsemius, MD > > West Hartford, CT > > > > > > [[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. > [[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.