From 6468bc31254baeac7dad90a38715714291be30ae Mon Sep 17 00:00:00 2001 From: Johannes Ranke Date: Wed, 2 Mar 2022 08:30:46 +0100 Subject: Add a test for tffm0() --- R/tffm0.R | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'R') diff --git a/R/tffm0.R b/R/tffm0.R index bb5f4cf5..56283a5d 100644 --- a/R/tffm0.R +++ b/R/tffm0.R @@ -1,15 +1,18 @@ #' Transform formation fractions as in the first published mkin version #' -#' The transformed fractions can be restricted between 0 and 1 in model -#' optimisations. Therefore this transformation was used originally in mkin. It -#' was later replaced by the [ilr] transformation because the ilr transformed +#' This transformation was used originally in mkin, in order to implement a +#' constraint for the sum of formation fractions to be smaller than 1. It was +#' later replaced by the [ilr] transformation because the ilr transformed #' fractions can assumed to follow normal distribution. As the ilr #' transformation is not available in [RxODE] and can therefore not be used in -#' the nlmixr modelling language, this transformation is currently used for -#' translating mkin models with formation fractions to more than one target -#' compartment for fitting with nlmixr in [nlmixr_model]. However, -#' this implementation cannot be used there, as it is not accessible -#' from RxODE. +#' the nlmixr modelling language, the original transformation is currently used +#' for translating mkin models with formation fractions to more than one target +#' compartment for fitting with nlmixr in [nlmixr_model]. However, this +#' implementation cannot be used there, as it is not accessible from RxODE. +#' +#' If the transformed formation fractions are restricted to the interval +#' between 0 and 1, the sum of backtransformed values is restricted +#' to this interval. #' #' @param ff Vector of untransformed formation fractions. The sum #' must be smaller or equal to one -- cgit v1.2.1