R/shape_sim.R

In npdsim: Simulate Demand and Attributes for New Products

#' Generate the shape of demand
#'
#' @description
#' Generate the shape of demand for new products by specifying their life cycle
#' shape and the length of their life cycle
#'
#' @param periods_number Number of time periods of the products life cycle
#' @param shape_number Number of generic shapes
#' @param shape_type Type of shape to generate. It can take the values: "triangle",
#'            "trapezoid", "bass", "random" and "intro & growth".
#'              The type "random" picks one of the types "triangle",
#'            "trapezoid", "bass" randomly for each product.
#'            The type "intro & growth" is used for the shapes of the introduction
#'            and growth phases.
#'
#' @return A numeric dateframe of three columns: time, shape and assigned_shape
#' @export
#'
#' @examples
#' shape_sim(periods_number=20, shape_number=5)
#' shape_sim(periods_number=20, shape_number=5,shape_type="trapezoid")
shape_sim <- function(periods_number,shape_number,shape_type="random") {

  stopifnot("periods_number must be a numeric"=is.numeric(periods_number))
  stopifnot("shape_number must be a numeric"=is.numeric(shape_number))
  stopifnot("shape_type must take one of the folllwing shapes: triangle, trapezoid, bass, random and intro & growth "=shape_type %in% c("triangle", "trapezoid", "bass", "random", "intro & growth"))


  if (shape_type=="triangle") {

    return(shape_sim_triangle(periods_number,
                              shape_number))

  }


  if (shape_type=="trapezoid") {

    return(shape_sim_trapezoid(periods_number,
                              shape_number))

  }


  if (shape_type=="bass") {

    return(shape_sim_bass(periods_number,
                              shape_number))

  }


  if (shape_type=="random") {


    return(shape_sim_random(periods_number,
                           shape_number))

  }

  if (shape_type=="intro & growth") {


    return(shape_sim_ig(periods_number,
                            shape_number))

  }

}