R/logit-expit.R

In kevinwang09/APES: Approximated Exhaustive Search for GLM

#' @title The logit/expit tranformation
#' @param x numeric
#' @export
#' @rdname transforms
#' @examples
#' curve(logit, from = 0.1, to = 0.9)
logit = function(x){
  stopifnot(any(x > 0) | any(x < 1))

  return(log(x) - log(1-x))
}

#' @param x numeric
#' @export
#' @rdname transforms
#' @examples
#' curve(expit, from = -5, to = 5)
expit = function(x){
  return(1/(1+exp(-x)))
}