R/compareNumericVectors.R

In msxakk89/dat: Data Analyst Toolkit (dat): a library of tools for data analysts and scientists

#' Compare two numeric vectors for greatness
#' 
#' In this function a numeric vector supersedes (comes after) another numeric vector if the left-most differeing number between the two vectors is higher in value.
#' 
#' Function starts by comparing the first element from each sequence. If they are equal, it goes on to the next element, and so on, until it finds elements that differ. 
#' Subsequent elements are not considered (even if they are really big).
#' For example c(0,1,200000) is NOT greater than c(0,3,4)
#' 
#' @param lst List of length 2 containing the vectors to be compared. Vectors must be of the same length.
#' @return 1 if first element is greater, 2 if second element is greater.
#' @export 

compareNumericVectors = function(lst){
  stopifnot(length(lst)==2 & length(lst[[1]])==length(lst[[2]]))
  
  firstVector = lst[[1]]
  secondVector = lst[[2]]
  vectorSize = length(firstVector)
  for(i in 1:vectorSize){
    if(firstVector[i] == secondVector[i]){
      next
    }
    else{
      if(firstVector[i] > secondVector[i]){
        return(1)
      }
      else{
        return(2)
      }
    }
  }
}