Dear R users, I am trying to sum number that exist in another vector up to i, then increment i and repeat. Sorry. It's hard to explain but basically I am trying to do the following: test <- c(1,2,3,4); test2 <- c(3,5,6,7,2,8,8,4,4); test3 <- c(10,20,30,40); tmp <- 0; for (i in 1:length(test)){ tmp[i] <- sum(test3[which(test[1:i] %in% test2)]); }
so when i = 1, tmp[i] = 0 because test[1]=1 is not in test2 and when i = 3, tmp[i] = 50 = test3[2] + test3[3] because test[2:3] is in test2 Problem is test has 5000+ entries. How do I do the same thing without the loop? Thanks in advance. -- View this message in context: http://r.789695.n4.nabble.com/sequential-sum-tp4387670p4387670.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.