R/get.curve.y.R

In yanxianUCSB/yxhelper: Yx's Personal R packages

#' Title
#'
#' @param curve
#' @param x
#'
#' @return
#' @export
#'
#' @examples
get.curve.y <- function(curve, x = seq_along(curve)) {
    if(sum(which(x < 1 | x > length(curve)))) return(NULL)
    curve.y <- c()
    ce <- ceiling(x)
    fl <- floor(x)
    curve.y[which(ce - fl == 0)] <- curve[fl][which(ce - fl == 0)]
    curve.y[which(ce - fl != 0)] <-
        ((curve[ce] - curve[fl]) / (ce - fl) * (x - fl) + curve[fl])[which(ce - fl != 0)]
    return(curve.y)
}