HI, With merge(), you could use: merge(new,old,by=c("group","ID"),all.x=TRUE) # group ID SomedataCol #1 1 23 9.2 #2 1 542 NA #3 1 800 NA #4 2 23 4.2 #5 2 45 15.6 #6 2 2318 NA #7 3 232 18.0 #8 3 800 3.3 #9 3 1345 21.1 A.K.
----- Original Message ----- From: lind35 <li...@vcu.edu> To: r-help@r-project.org Cc: Sent: Sunday, November 25, 2012 1:22 PM Subject: [R] "argument is missing, with no default" OR "replacement has length zero" Hello, I have a new data set and an old data set. Both have the same columns representing the same sort of measure. Within each data set (old and new) are 18 groups (simplified to three groups below). Within each group are individuals with unique ID numbers. These ID numbers may be the same as other ID numbers in different groups, but a particular ID number only appears once in each group. The old data set does not include all of the individuals from the new data set - meaning IDs within groups in the new data set are not found within the old data set or visa versa. I am trying to extract data from a particular column for unique individuals within a unique group from the old data set and put that info into a column within the row for that particular unique individual/group in the new data set. However, I keep coming up with R errors. Basically it's set up like this (i've simplified the data to illustrate the important stuff) old <- read.csv("/Users/Me/Desktop/old data.csv") new <- read.csv("/Users/Me/Desktop/new data.csv") > new [group] [ID] [column where I want to put the data, currently blank] [1,] 1 800 __ [2,] 1 23 __ [3,] 1 542 __ [4,] 2 23 __ [5,] 2 2318 __ [6,] 2 45 __ [7,] 3 1345 __ [8,] 3 800 __ [9,] 3 232 __ > old [group] [ID] [data I want for the new.object] [1,] 1 300 12.2 [2,] 1 155 10.8 [3,] 1 23 9.2 [4,] 2 45 15.6 [5,] 2 1289 5.5 [6,] 2 23 4.2 [7,] 3 800 3.3 [8,] 3 232 18.0 [9,] 3 1345 21.1 #and this is what I want to get as an end result > new [1,] 1 800 __ [2,] 1 23 9.2 [3,] 1 542 __ [4,] 2 23 4.2 [5,] 2 2318 __ [6,] 2 45 15.6 [7,] 3 1345 21.1 [8,] 3 800 3.3 [9,] 3 232 18.0 I've tried the following codes but keep getting error messages > for (i in 1) { + new[i,3] <- old[which(old[,2] == new[i,2] & old[,1] == new[i,1]),3] + } Error in `[<-.data.frame`(`*tmp*`, i, 11, value = numeric(0)) : replacement has length zero #OR > for (i in 1) { + data[[i,11]] <- as.numeric(old[[which(old[[,22]] == data[[i,2]] & old[[,1]] == data[[i,1]]),46]]) + } Error in `[[.data.frame`(old, , 22) : argument "..1" is missing, with no default I just want to ignore the IDs in the old data set that aren't in the new data set. How do I do this? -- View this message in context: http://r.789695.n4.nabble.com/argument-is-missing-with-no-default-OR-replacement-has-length-zero-tp4650757.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. ______________________________________________ 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.