R/subset.R

In pbreheny/visreg: Visualization of Regression Models

#' Subset a visreg object
#'
#' Subset a visreg object so that only a portion of the full model is plotted.
#'
#' @param x A `visreg` object.
#' @param sub Logical expression indicating elements to keep, as in [subset()]
#' @param ... Not used.
#'
#' @examples
#' # Fit a model and construct a visreg object
#' airquality$Heat <- cut(airquality$Temp,3,labels=c("Cool","Mild","Hot"))
#' fit <- lm(Ozone~ Solar.R + Wind*Heat,data=airquality)
#' v <- visreg(fit, "Wind", by="Heat", plot=FALSE)
#'
#' # Plot only certain levels
#' vv <- subset(v, Heat %in% c("Cool", "Hot"))
#' plot(vv)
#'
#' # Plot only up to wind 15 mph
#' vv <- subset(v, Wind < 15)
#' plot(vv)
#' @export

subset.visreg <- function(x, sub, ...) {
  x$fit <- x$fit[eval(match.call()$sub, x$fit),]
  x$res <- x$res[eval(match.call()$sub, x$res),]
  x
}