R/gradient_from_data.R

In StratPal: Stratigraphic Paleobiology Modeling Pipelines

gradient_from_data = function(x){
  #' @export
  #' @title gradient or taphonomic conditions from data
  #'
  #' @param x list or data frame
  #'
  #' @returns a function for usage as gradient or taphonomic conditions, which can be passed to `apply_taphonomy` or `apply_niche`
  #'
  #' @description
    #' Constructs a gradient or taphonomic conditions from a dataframe or list. If `x` is a dataframe, the first two columns are used, if `x` is a list the first two elements are used. The first entry is used as time/stratigraphic position, and the second as gradient/recovery probability.
    #'
  #' @examples
    #' # water depth 2 km offshore as gradient
    #' t = scenarioA$t_myr
    #' l = list(t, scenarioA$wd_m[,"2km"])
    #' f = gradient_from_data(l)
    #' plot(t, f(t), type = "l")
  if (is.data.frame(x)){
    return(stats::approxfun(x = x[,1], y = x[,2], rule = 2))
  }
  if(is.list(x)){
    return(stats::approxfun(x = x[[1]], y = x[[2]], rule = 2))
  }
  stop("Input must be a list or a data frame")
}