R/NUEFC.R

In NUETON: Nitrogen Use Efficiency Toolkit on Numerics

#' Calculate NUE of a Food Chain (NUEFC)
#' @description
#' The N balance of the entire food chain system, in terms of N consumed as protein relative to N inputs.
#' Calculate NUEFC using the formula: NUEFC = Ncon / Ni
#' @param Ncon The value of N available for consumption
#' @param Ni Sum total of new N input
#' @returns The calculated NUEFC value.
#' @examples
#' Ncon <- 15.574
#' Ni <- c(2.92, 3.78, 4.68, 4.21)
#' NUEFC(Ncon, Ni)
#' @references
#' Primary: Congreves, K. A., Otchere, O., Ferland, D., Farzadfar, S., Williams, S., & Arcand, M. M. (2021, June 4).
#' Nitrogen Use Efficiency Definitions of Today and Tomorrow. Frontiers in Plant Science, 12.
#' https://doi.org/10.3389/fpls.2021.637108
#'
#' Secondary: Erisman, J. W., Sutton, M. A., Galloway, J., Klimont, Z., and Winiwarter, W. (2008).
#' How a century of ammonia synthesis changed the world. Nat. Geosci. 1, 636–639. doi: 10.1038/ngeo325
#' @export


NUEFC <- function(Ncon, Ni) {
  if (length(Ni) == 0 || Ncon == 0 || sum(Ni) == 0) {
    stop("Ni vector should not be empty, Ncon and the sum of Ni values should not be zero.")
  }
  NUEFC <- Ncon / sum(Ni)
  return(NUEFC)
}