Compute the gini index with (optional) weights

gini function

#' Compute gini index.
#' 
#' Compute the gini index with (optional) weights.
#' 
#' @param x A numeric vector with the data.
#' @param weights A numeric vector with sample weights.
#' @return res An atomic vector with the gini index.
gini <- function(x, weights = NULL, na.rm = FALSE) {
  
  if(na.rm){
    
    index_nas <- is.na(x)
    x <- x[!index_nas]
    weights <- weights[!index_nas]
    
  }
  
  if(any(is.na(x))){
    
    warning("There are NAs in 'x'. Use na.rm = TRUE to remove them.")
    return(NA_real_)
    
  }else if(!is.null(weight) & any(is.na(weight))){
    
    warning("There are NAs in 'weights'. Use na.rm = TRUE to remove them.")
    return(NA_real_)
    
  }else{
  
  ox <- order(x)
  x <- x[ox]
  weights <- weights[ox]/sum(weights)
  p <- cumsum(weights)
  nu <- cumsum(weights*x)
  n <- length(nu)
  nu <- nu/nu[n]
  res <- sum(nu[-1]*p[-n])-sum(nu[-n]*p[-1])
  
  return(res)
  }
}

my_gini_function.txt

#' Compute gini index.
#' 
#' Compute the gini index with (optional) weights.
#' 
#' @param x A numeric vector with the data.
#' @param weights A numeric vector with sample weights.
#' @return res An atomic vector with the gini index.
gini <- function(x, weights = NULL, na.rm = FALSE) {
  
  if(na.rm){
    
    index_nas <- is.na(x)
    x <- x[!index_nas]
    weights <- weights[!index_nas]
    
  }
  
  if(any(is.na(x))){
    
    warning("There are NAs in 'x'. Use na.rm = TRUE to remove them.")
    return(NA_real_)
    
  }else if(!is.null(weight) & any(is.na(weight))){
    
    warning("There are NAs in 'weights'. Use na.rm = TRUE to remove them.")
    return(NA_real_)
    
  }else{
  
  ox <- order(x)
  x <- x[ox]
  weights <- weights[ox]/sum(weights)
  p <- cumsum(weights)
  nu <- cumsum(weights*x)
  n <- length(nu)
  nu <- nu/nu[n]
  res <- sum(nu[-1]*p[-n])-sum(nu[-n]*p[-1])
  
  return(res)
  }
}