R/lnorm.R

In ssdtools: Species Sensitivity Distributions

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#       https://www.apache.org/licenses/LICENSE-2.0
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#' @describeIn ssd_p Cumulative Distribution Function for Log-Normal Distribution
#' @export
#' @examples
#' 
#' ssd_plnorm(1)
ssd_plnorm <- function(q, meanlog = 0, sdlog = 1, lower.tail = TRUE, log.p = FALSE) {
  pdist("lnorm", q = q, meanlog = meanlog, sdlog = sdlog, 
        lower.tail = lower.tail, log.p = log.p)
}

#' @describeIn ssd_q Cumulative Distribution Function for Log-Normal Distribution
#' @export
#' @examples
#' 
#' ssd_qlnorm(0.5)
ssd_qlnorm <- function(p, meanlog = 0, sdlog = 1, lower.tail = TRUE, log.p = FALSE) {
  qdist("lnorm", p = p, meanlog = meanlog, sdlog = sdlog, 
        lower.tail = lower.tail, log.p = log.p)
}

#' @describeIn ssd_r Random Generation for Log-Normal Distribution
#' @export
#' @examples
#' 
#' set.seed(50)
#' hist(ssd_rlnorm(10000), breaks = 1000)
ssd_rlnorm <- function(n, meanlog = 0, sdlog = 1, chk = TRUE) {
  rdist("lnorm", n = n, meanlog = meanlog, sdlog = sdlog, chk = chk)
}

slnorm <- function(data, pars = NULL) {
  if(!is.null(pars)) return(pars)
  
  x <- mean_weighted_values(data)
  
  list(
    meanlog = mean(log(x), na.rm = TRUE),
    log_sdlog = log(sd(log(x), na.rm = TRUE))
  )
}

plnorm_ssd <- function(q, meanlog, sdlog) {
  if(sdlog <= 0) return(NaN)
  stats::plnorm(q, meanlog, sdlog);
}

qlnorm_ssd <- function(p, meanlog, sdlog) {
  if(sdlog <= 0) return(NaN)
  stats::qlnorm(p, meanlog, sdlog)
}

rlnorm_ssd <- function(n, meanlog, sdlog) {
  if(sdlog <= 0) return(rep(NaN, n))
  stats::rlnorm(n, meanlog, sdlog)
}