R/gratia_derivatives.R

In galamm: Generalized Additive Latent and Mixed Models

##' @importFrom gratia derivatives
##' @export derivatives
NULL

#' Derivatives of estimated smooth via finite differences
#'
#' This function uses \code{gratia::derivatives} to compute derivatives of
#' estimated smooth via finite differences. See
#' [gratia::derivatives()] for details. When \code{object} is not of class
#' \code{galamm}, it is forwarded to \code{gratia::derivatives()}.
#'
#' @param object An object of class \code{galamm} returned from
#'   \code{\link{galamm}}.
#' @param ... Other arguments passed on to [gratia::derivatives()].
#' @return A tibble.
#' @export
#' @aliases derivatives derivatives.galamm
#' @family details of model fit
#' @examples
#' dat <- subset(cognition, domain == 1 & item == "11")
#' dat$y <- dat$y[, 1]
#' mod <- galamm(y ~ s(x) + (1 | id), data = dat)
#'
#' dd <- derivatives(mod)
#' draw(dd)
#'
derivatives.galamm <- function(object, ...) {
  if (is.null(object$gam) || length(object$gam) == 0) {
    stop("No GAM object")
  }
  gratia::derivatives(object$gam, ...)
}