Why the last "which" in the following example doesn't work? Is there a simple way to identify the indices of array elements that meet multiple criteria? Thanks. YC Tao > x<-1:10 > which(x<5) [1] 1 2 3 4 > which(x>2) [1] 3 4 5 6 7 8 9 10 > which(x<5 && x>2) numeric(0) __________________________________ Dress up your holiday email, Hollywood style. Learn more.