Andras, Is there an error in your post or am I missing something?
df[, 9] is made up of the last (9th) element of each of a, b, c, and d. The minimum value for sum(df[, 9]) is 0. Given your conditions, there are many, many ways to get this result. Here is just one example: a <-c(1,1,1,1,1,0,0,0,0) b <-c(1,0,1,1,1,1,0,0,0) c <-c(1,0,1,1,0,0,0,0,0) d <-c(1,1,1,1,0,1,0,0,0) df <-rbind(a,b,c,d) df <-cbind(df,h=c(sum(a)*8,sum(b)*8,sum(c)*8,sum(d)*8)) df <-cbind(df,df[,8]*c(1,2,3,2)) Jean On Wed, Oct 1, 2014 at 7:30 PM, Andras Farkas <motyoc...@yahoo.com> wrote: > Dear All, > > please provide help with the following: > > we have > > a <-c(0,1,1,0,1,0,0,0,0) > b <-c(0,0,0,1,0,0,0,0,0) > c <-c(1,0,1,0,1,1,0,0,0) > d <-c(0,1,0,1,0,1,0,0,0) > df <-rbind(a,b,c,d) > df <-cbind(df,h=c(sum(a)*8,sum(b)*8,sum(c)*8,sum(d)*8)) > df <-cbind(df,df[,8]*c(1,2,3,2)) > > I would like to minimize the value for sum(df[,9]) under the following > conditions: > > 1. all values of a,b,c, and d are binary variables and are the variables > to change to get the optimal result > 2. sum(a), sum(b), and sum(d) should be each 5 or more > 3. sum(c) should be 3 or less > 4. a[2], a[3], b[2], d[7] and d[8] are fixed to their current values. > > any thoughts or reference examples you could help with is greatly > appreciated > > thanks > > andras > > ______________________________________________ > 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.
