Need help with finding out approx over each row of a matrix. Here is the setup: years <- matrix(c(1,2,3,1,2,3),nrow=2, ncol=3,byrow=TRUE) rates <- matrix(c(1,2,3,11,12,13), nrow = 2, ncol=3, byrow=TRUE) points <- matrix(c(1.5, 1.5), nrow=2, ncol=1, byrow=TRUE) so basically i have above three vectors years is the X vector, rates is the Y vector and points is the points at which each row of X, Y has to be interpolated. I have tried every possible combination of approx & apply but i am unable to figure out. Any help will be greatly appreciated. -- Ramneek