Thank you David. However, this will not work for me. If the group ID selected then all of its observation should be included.
On Mon, Feb 11, 2019 at 4:51 PM David L Carlson <dcarl...@tamu.edu> wrote: > > First expand your data frame into a vector where G1 is repeated 25 times, G2 > is repeated 15 times, etc. Then draw random samples of 40 from that vector: > > > grp <- rep(mydat$group, mydat$count) > > grp.sam <- sample(grp, 40) > > table(grp.sam) > grp.sam > G1 G2 G3 G4 G5 > 10 9 5 13 3 > > ---------------------------------------- > David L Carlson > Department of Anthropology > Texas A&M University > College Station, TX 77843-4352 > > > -----Original Message----- > From: R-help <r-help-boun...@r-project.org> On Behalf Of Val > Sent: Monday, February 11, 2019 4:36 PM > To: r-help@R-project.org (r-help@r-project.org) <r-help@r-project.org> > Subject: [R] Select > > Hi all, > > I have a data frame with tow variables group and its size. > mydat<- read.table( text='group count > G1 25 > G2 15 > G3 12 > G4 31 > G5 10' , header = TRUE, as.is = TRUE ) > > I want to select group ID randomly (without replacement) until the > sum of count reaches 40. > So, in the first case, the data frame could be > G4 31 > 65 10 > > In other case, it could be > G5 10 > G2 15 > G3 12 > > How do I put sum of count variable is a minimum of 40 restriction? > > Than k you in advance > > > > > > > I want to select group ids randomly until I reach the > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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 -- To UNSUBSCRIBE and more, see 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.
