Hi Jason, This is one way;
c1 <- seq(2,20,2) c2 <- seq(1,19,2) c3 <- cbind(c1,c2) c3[,1][which(c3[,1]<12)] <- -1 c3[,2][which(c3[,2]>10)] <- -1 Muhammad On Fri, 3 Jun 2011, Jason024 wrote:
I have a data frame like this: col1 col2 r1 2 1 r2 4 3 r3 6 5 r4 8 7 r5 10 9 r6 12 11 r7 14 13 r8 16 15 r9 18 17 r10 20 19 I want to modify this data frame, for example, assign every row in column col1 and col2 to -1 if the values in col1 is less than 12 and values in col2 is greater than 10. The result should look like this: col1 col2 r1 -1 1 r2 -1 3 r3 -1 5 r4 -1 7 r5 -1 9 r6 12 -1 r7 14 -1 r8 16 -1 r9 18 -1 r10 20 -1 I have been struggling to make it to work. Any help is appreciated! Jason -- View this message in context: http://r.789695.n4.nabble.com/modify-a-data-frame-by-values-in-the-columns-tp3571995p3571995.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.
