Hi, You could try: mat1<-matrix(dat3[rowSums(dat3[,2:3])!=dat3[,4],1],ncol=1,dimnames=list(NULL,"MW_EEsDue_ERRORS")) mat1 # MW_EEsDue_ERRORS #[1,] 1882 #[2,] 1884 #[3,] 1885 A.K.
#Let's say I have the following data set: dat3 = data.frame(A_CaseID = c(1881, 1882, 1883, 1884, 1885), B_MW_EEsDue1 = c(2, 2, 1, 4, 6), C_MW_EEsDue2 = c(5, 5, 4, 1, 6), D_MW_EEsDueTotal = c(7, 9, 5, 6, 112)) dat3 # A_CaseID B_MW_EEsDue1 C_MW_EEsDue2 D_MW_EEsDueTotal # 1 1881 2 5 7 # 2 1882 2 5 9 # 3 1883 1 4 5 # 4 1884 4 1 6 # 5 1885 6 6 112 # I want to: #CREATE A NEW 1-COLUMN MATRIX (of unknown #rows) LISTING ONLY "A"'s WHERE "D != B + C" #THIS COLUMN CAN BE LABELED "MW_EEsDue_ERRORS", and output for this example should be: # MW_EEsDue_ERRORS # 1 1882 # 2 1884 # 3 1885 #What is the best way to do this? Thanks for your time. BNC ______________________________________________ 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.