HI, Try this: set.seed(1) dat1<-data.frame(col1=sample(0:1,1000,replace=TRUE),col2=sample(0:10,1000,replace=TRUE))
count(dat1$col1==1 & dat1$col2>5)[2,2] #[1] 209 A.K. ----- Original Message ----- From: SirRon <thechrist...@gmx.at> To: r-help@r-project.org Cc: Sent: Sunday, September 16, 2012 6:41 AM Subject: [R] Count based on 2 conditions [Beginner Question] Hello, I'm working with a dataset that has 2 columns and 1000 entries. Column 1 has either value 0 or 1, column 2 has values between 0 and 10. I would like to count how often Column 1 has the value 1, while Column 2 has a value greater 5. This is my attempt, which works but doesn't seem to be very efficient, especially when testing different values or columns. count=0 for (i in 1:1000) { if(dataset[i,2]>5 && ind[i,1]==1) { count=count+1}} I'm looking for a more efficient/elegant way to do this! Thanks! -- View this message in context: http://r.789695.n4.nabble.com/Count-based-on-2-conditions-Beginner-Question-tp4643282.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.