R/methodFunFEM.R

In latrend: A Framework for Clustering Longitudinal Data

#' @include method.R

#' @name interface-funFEM
#' @rdname interface-funFEM
#' @title funFEM interface
#' @seealso [lcMethodFunFEM] \link[funFEM]{funFEM-package}
#' @keywords internal
NULL

setClass('lcMethodFunFEM', contains = 'lcMatrixMethod')

#' @export
#' @title Specify a FunFEM method
#' @inheritParams lcMatrixMethod-class
#' @inheritParams lcMethodKML
#' @param basis The basis function. By default, a 3rd-order B-spline with 10 breaks is used.
#' @param ... Arguments passed to [funFEM::funFEM].
#' The following external arguments are ignored: fd, K, disp, graph.
#' @examples
#' data(latrendData)
#'
#' if (require("funFEM") && require("fda")) {
#'   method <- lcMethodFunFEM("Y", id = "Id", time = "Time", nClusters = 3)
#'   model <- latrend(method, latrendData)
#'
#'   method <- lcMethodFunFEM("Y",
#'    basis = function(time) {
#'       create.bspline.basis(time, nbasis = 10, norder = 4)
#'    }
#'   )
#' }
#' @family lcMethod implementations
#' @references
#' \insertRef{bouveyron2015funfem}{latrend}
lcMethodFunFEM = function(
  response,
  time = getOption('latrend.time'),
  id = getOption('latrend.id'),
  nClusters = 2,
  basis = function(time) fda::create.bspline.basis(time, nbasis = 10, norder = 4),
  ...
) {
  mc = match.call.all()
  mc$Class = 'lcMethodFunFEM'
  do.call(new, as.list(mc))
}

#' @rdname interface-funFEM
setMethod('getArgumentDefaults', 'lcMethodFunFEM', function(object) {
  c(
    formals(lcMethodFunFEM),
    formals(funFEM::funFEM),
    callNextMethod()
  )
})

#' @rdname interface-funFEM
setMethod('getArgumentExclusions', 'lcMethodFunFEM', function(object) {
  union(
    callNextMethod(),
    c('fd', 'K', 'disp', 'graph')
  )
})

#' @rdname interface-funFEM
setMethod('getName', 'lcMethodFunFEM', function(object) 'functional subspace clustering with FunFEM')

#' @rdname interface-funFEM
setMethod('getShortName', 'lcMethodFunFEM', function(object) 'funfem')

#' @rdname interface-funFEM
setMethod('preFit', 'lcMethodFunFEM', function(method, data, envir, verbose, ...) {
  requireNamespace('fda')
  requireNamespace('funFEM')

  e = callNextMethod()
  e$basis = method$basis(range(e$times))
  e$fd = fda::smooth.basis(e$times, t(e$dataMat), e$basis)$fd

  return(e)
})

#' @rdname interface-funFEM
#' @inheritParams fit
setMethod('fit', 'lcMethodFunFEM', function(method, data, envir, verbose, ...) {
  args = as.list(method, args = funFEM::funFEM)
  args$fd = envir$fd
  args$K = method$nClusters
  args$disp = FALSE
  args$graph = FALSE

  model = do.call(funFEM::funFEM, args)
  model$basis = envir$basis
  model$fd = envir$fd

  new(
    'lcModelFunFEM',
    method = method,
    data = data,
    model = model,
    clusterNames = make.clusterNames(method$nClusters)
  )
})