You seem to be saving 'myid' and then overwriting it with the last statement:
result[[i]] <- result[[i]][c(5, 1:4)] Why doesn't 'merge' work for you? I tried it on your data, and seem to get back the same number of rows; may not be in the same order, but the content looks the same, and it does have 'myid' on it. Jim Holtman Data Munger Guru What is the problem that you are trying to solve? Tell me what you want to do, not how you want to do it. On Tue, Dec 22, 2015 at 12:27 PM, Dimitri Liakhovitski < [email protected]> wrote: > Hello! > I have a solution for my task that is based on a loop. However, it's > too slow for my real-life problem that is much larger in scope. > However, I cannot use merge. Any advice on how to do it faster? > Thanks a lot for any hint on how to speed it up! > > # I have 'mydata' data frame: > set.seed(123) > mydata <- data.frame(myid = 1001:1100, > version = sample(1:20, 100, replace = T)) > head(mydata) > table(mydata$version) > > # I have 'myinfo' data frame that contains information for each 'version': > set.seed(12) > myinfo <- data.frame(version = sort(rep(1:20, 30)), a = rnorm(60), b = > rnorm(60), > c = rnorm(60), d = rnorm(60)) > head(myinfo, 40) > > ### MY SOLUTION WITH A LOOP: > ### Looping through each id of mydata and grabbing > ### all columns from 'myinfo' for the corresponding 'version': > > # 1. Creating placeholder list for the results: > result <- split(mydata[c("myid", "version")], f = list(mydata$myid)) > length(result) > (result)[1:3] > > > # 2. Looping through each element of 'result': > for(i in 1:length(result)){ > id <- result[[i]]$myid > result[[i]] <- myinfo[myinfo$version == result[[i]]$version, ] > result[[i]]$myid <- id > result[[i]] <- result[[i]][c(5, 1:4)] > } > result <- do.call(rbind, result) > head(result) # This is the desired result > > -- > Dimitri Liakhovitski > > ______________________________________________ > [email protected] 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. > [[alternative HTML version deleted]] ______________________________________________ [email protected] 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.
