This constraint was not clear in your original sample data set. Can you expand the data set to clarify how this requirement REALLY works?
On February 11, 2019 3:00:15 PM PST, Val <valkr...@gmail.com> wrote: >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. -- Sent from my phone. Please excuse my brevity. ______________________________________________ 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.
