Hi Could you use something along the lines of the following:
transposedat<-t(dat) transposedat$oddrow<-(1:ncol(dat))%%2 oddcolumns<-t(transposedat[transposedat$oddrow==1,]) Now you should have the odd columns in a single dataframe. gzero<-matrix(oddcolumns>0,nrow=nrow(oddcolumns),ncol=ncol(oddcolumns)) colSums(gzero) Best regards Per Jensen On 6/20/06, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > > I've tried and give up. I have a matrix of say 200 columns and 400 rows. > > For each odd ( or even i suppose if i wanted to )column, > I want to know the number of rows in which the value is greater than zero. > > So, I did sapply(tempMatrix,2,function(x) sum( x > 0 )) > > this almost works but i don't know how to tell > it to only do the odd columns. my guess is , like everything else > in R, this is possible. Thanks. > > ______________________________________________ > [email protected] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html > [[alternative HTML version deleted]] ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
