R/method-mcmcdb_init.R

In jrnold/mcmcdb: MCMC sample database classes

#' @include package.R
#' @include class-McmcdbMem.R
#' @exportMethod mcmcdb_init
NULL

#' @name mcmcdb_init-methods
#' @rdname mcmcdb_init-methods
#' @aliases mcmcdb_init-methods
#' @aliases mcmcdb_init
#' @title Get parameter initial values from a Mcmcdb object
#'
#' @description Get the parameter initial values used in model estimation,
#' if it was saved in the object.
#' @param object An object for which the method is defined.
#' @param flatten \code{logical} Whether to return the parameter values
#' in their flattened or original array shapes.
#' @return If \code{flattened=TRUE}, then a \code{matrix}; rows are chains, columns
#' are flat parameters. If \code{flattened=FALSE}, then a list of
#' numeric \code{array} objects; the elements of the list are chains, the
#' arrays are the parameter arrays.
setGeneric("mcmcdb_init",
           function(object, ...) {
             standardGeneric("mcmcdb_init")
           })

name <- function(x, value) {
  names(x) <- value
  x
}

#' @rdname mcmcdb_init-methods
#' @aliases mcmcdb_init,McmcdbMem-method
setMethod("mcmcdb_init", "McmcdbMem",
          function(object, flatten=TRUE) {
            inits <- daply(object@flatpar_chains, "chain_id",
                           function(x) {
                             name(x[["init"]], x[["flatpar"]])
                           })
            if (flatten) {
              inits
            } else {
              inits <- alply(inits, 1, mcmcdb_unflatten,
                             parameters = object@parameters)
              for (i in c("split_type", "split_labels")) {
                attr(inits, i) <- NULL
              }
              inits
            }
          })