ifelse is vectorized but there is no way you could know what's happening with that command because you have rnorm(1) for both conditions. I think you mean to have something different in one of them ?
Whewn I run your code in my R session, I get 10 values for y1, so there isn't anything wrong except That you have the same statement for both cases. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Tuesday, December 12, 2006 3:13 PM To: r-help@stat.math.ethz.ch Subject: [R] ifelse question Dear R-helpers, How come that in the following code the rnorm() function is evaluated only once for each branch of the 'ifelse' ? x <- rnorm(10) y1 <- ifelse(x > 0, rnorm(1) , rnorm(1)) What is the right way to make it called/evaluated for each row, apart from a 'for' loop ? Thanks, Jacques. ______________________________________________ R-help@stat.math.ethz.ch 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. -------------------------------------------------------- This is not an offer (or solicitation of an offer) to buy/se...{{dropped}} ______________________________________________ R-help@stat.math.ethz.ch 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.