N highest of vector. This function was created by [Zach](https://stackoverflow.com/users/345660/zach) in this [post](https://stackoverflow.com/questions/2453326/fastest-way-to-find-second-third-highest-lowest-value-in-vector-or-column). I just keep it here for storage purposes.

maxN.R

maxN <- function(x, N=2, decreasing = FALSE){
  len <- length(x)
  if(N>len){
    warning('N greater than length(x).  Setting N=length(x)')
    N <- length(x)
  }
  if (decreasing == FALSE) {
    sort(x,partial=len-N+1)[len-N+1]
  } else {
    -sort(-x,partial=len-N+1)[len-N+1]
  }
}