[R-gui] runif function
On Nov 8, 2007, at 12:07 PM, shweta wrote:
Hi , I was trying to generate random data in R using the runif function. But I am not sure how do I combine the x and y to get a 2d array/matrix in a variable z. As seen below I am getting the same numbers in x as 1 and in y as 2.1 respectively. I would like to get different & random numbers in x & y. Please let me know.
Looking at ?runif, you can see that the syntax for runif is: runif(n, min=0, max=1) So when you call runif(N,1), what you really call is runif (N,min=1,max=1), so you are asking R to generate random numbers between 1 and 1. Of course they will all be equal to 1. Try runif(N), or specify both a min and a max. PS: Not sure what this has to do with GUI though, isn't that more appropriate to R-help instead of r-sig-gui?
x <- array(runif(N,1),dim=c(N,1))
x
[,1] [1,] 1 [2,] 1 [3,] 1 [4,] 1 [5,] 1 [6,] 1 [7,] 1 [8,] 1 [9,] 1 [10,] 1
y <- array(2*x + runif(N,1)/10) y
[1] 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 2.1 Thanks & Regards, Shweta.
Haris Skiadas Department of Mathematics and Computer Science Hanover College