Dear All, please help with the following if you can:
we have: simt <-seq(0,147,by=1) simc <-50*exp(-0.01*simt) out1.2 <-data.frame(simt,simc) AUC <-c(0,apply(matrix(simc),2,function(x) (diff(simt)*(x[-1]+x[-length(x)]))/2 )) df <-cbind(out1.2,AUC) z <-cumsum(rep(24,max(out1.2$simt/24))) #### first24 <-sum(unlist(c(subset(df, df[, 'simt'] > 0 & df[, 'simt'] <= z[1], 3)))) second24 <-sum(unlist(c(subset(df, df[, 'simt'] > z[1] & df[, 'simt'] <= z[2], 3)))) third24 <-sum(unlist(c(subset(df, df[, 'simt'] > z[2] & df[, 'simt'] <= z[3], 3)))) fourth24 <-sum(unlist(c(subset(df, df[, 'simt'] > z[3] & df[, 'simt'] <= z[4], 3)))) fifth24 <-sum(unlist(c(subset(df, df[, 'simt'] > z[4] & df[, 'simt'] <= z[5], 3)))) sixth24 <-sum(unlist(c(subset(df, df[, 'simt'] > z[5] & df[, 'simt'] <= z[6], 3)))) last24 <-sum(unlist(c(subset(df, df[, 'simt'] > z[6] , 3)))) my end result is to get this vector: c(first24,second24,third24,fourth24,fifth24,sixth24,last24) #### the important aspect is that z can be of different length, depending on simt, so what I am trying to do is to code the section between the #### tags above to accommodate any length of z that is greater then 0. I thought of split( df , f = df$id ), where we would need to add a column with name id to df based on the values in z in such a way where for example all rows of id where simt <=z[1] would be 1 (or a o whatever) , and 2 (or b or whatever) if simt >z[1] and <=z[2], and so on, then we could split df based on id and could work with respective columns... This is one thought, but having a hard time figuring out how to add the id column as such that may accommodate z of changing lengths... Or any other ideas that are more suitable would be welcome, thanks, Andras [[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.