#'
#' @description \code{clusteringTask1()} runs one full stage-1 task, which consists in
#' iterated stage 1 clustering (on nb_curves / ntasks energy contributions, computed
-#' through discrete wavelets coefficients). \code{computeClusters1()} and
-#' \code{computeClusters2()} correspond to the atomic clustering procedures respectively
-#' for stage 1 and 2. The former applies the clustering algorithm (PAM) on a
-#' contributions matrix, while the latter clusters a chunk of series inside one task
-#' (~max nb_series_per_chunk)
+#' through discrete wavelets coefficients).
+#' \code{clusteringTask2()} runs a full stage-2 task, which consists in synchrones
+#' and then WER distances computations, before applying the clustering algorithm.
+#' \code{computeClusters1()} and \code{computeClusters2()} correspond to the atomic
+#' clustering procedures respectively for stage 1 and 2. The former applies the
+#' clustering algorithm (PAM) on a contributions matrix, while the latter clusters
+#' a chunk of series inside one task (~max nb_series_per_chunk)
#'
#' @param indices Range of series indices to cluster in parallel (initial data)
#' @param getContribs Function to retrieve contributions from initial series indices:
#' @rdname clustering
#' @export
-computeClusters1 = function(contribs, K1)
- cluster::pam(contribs, K1, diss=FALSE)$id.med
-
-#' @rdname clustering
-#' @export
-computeClusters2 = function(medoids, K2,
+clusteringTask2 = function(medoids, K2,
getRefSeries, nb_ref_curves, nb_series_per_chunk, ncores_clust=1,verbose=FALSE,parll=TRUE)
{
+ if (nrow(medoids) <= K2)
+ return (medoids)
synchrones = computeSynchrones(medoids,
getRefSeries, nb_ref_curves, nb_series_per_chunk, ncores_clust, verbose, parll)
distances = computeWerDists(synchrones, ncores_clust, verbose, parll)
- #TODO: if PAM cannot take big.matrix in input, cast it before... (more than OK in RAM)
- medoids[ cluster::pam(distances, K2, diss=TRUE)$medoids , ]
+ # PAM in package 'cluster' cannot take big.matrix in input: need to cast it
+ mat_dists = matrix(nrow=K1, ncol=K1)
+ for (i in seq_len(K1))
+ mat_dists[i,] = distances[i,]
+ medoids[ computeClusters2(mat_dists,K2), ]
}
+#' @rdname clustering
+#' @export
+computeClusters1 = function(contribs, K1)
+ cluster::pam(contribs, K1, diss=FALSE)$id.med
+
+#' @rdname clustering
+#' @export
+computeClusters2 = function(distances, K2)
+ cluster::pam(distances, K2, diss=TRUE)$id.med
+
#' computeSynchrones
#'
#' Compute the synchrones curves (sum of clusters elements) from a matrix of medoids,
#' @param getSeries Access to the (time-)series, which can be of one of the three
#' following types:
#' \itemize{
-#' \item matrix: each line contains all the values for one time-serie, ordered by time
-#' \item connection: any R connection object (e.g. a file) providing lines as described above
+#' \item [big.]matrix: each line contains all the values for one time-serie, ordered by time
+#' \item connection: any R connection object providing lines as described above
+#' \item character: name of a CSV file containing series in rows (no header)
#' \item function: a custom way to retrieve the curves; it has only one argument:
#' the indices of the series to be retrieved. See examples
#' }
#' @param verbose Level of verbosity (0/FALSE for nothing or 1/TRUE for all; devel stage)
#' @param parll TRUE to fully parallelize; otherwise run sequentially (debug, comparison)
#'
-#' @return A matrix of the final medoids curves (K2) in rows
+#' @return A big.matrix of the final medoids curves (K2) in rows
#'
#' @examples
#' \dontrun{
runTwoStepClustering = function(inds)
{
- if (parll)
+ if (parll && ntasks>1)
require("epclust", quietly=TRUE)
indices_medoids = clusteringTask1(
inds, getContribs, K1, nb_series_per_chunk, ncores_clust, verbose, parll)
if (WER=="mix")
{
-
-
-
-
-#TODO: getSeries(indices_medoids) BAD ; il faudrait une big.matrix de medoids en entree
- #OK en RAM il y en aura 1000 (donc 1000*K1*17519... OK)
- #...mais du coup chaque process ne re-dupliquera pas medoids
-
-
- medoids2 = computeClusters2(getSeries(indices_medoids),
+ medoids1 = bigmemory::as.big.matrix( getSeries(indices_medoids) )
+ medoids2 = clusteringTask2(medoids1,
K2, getSeries, nb_curves, nb_series_per_chunk, ncores_clust, verbose, parll)
binarize(medoids2, synchrones_file, nb_series_per_chunk, sep, nbytes, endian)
return (vector("integer",0))
cat(paste("...Run ",ntasks," x stage 1 in parallel\n",sep=""))
if (WER=="mix")
{synchrones_file = paste(bin_dir,"synchrones",sep="") ; unlink(synchrones_file)}
- if (parll)
+ if (parll && ntasks>1)
{
cl = parallel::makeCluster(ncores_tasks)
varlist = c("getSeries","getContribs","K1","K2","verbose","parll",
- "nb_series_per_chunk","ncores_clust","sep","nbytes","endian")
+ "nb_series_per_chunk","ntasks","ncores_clust","sep","nbytes","endian")
if (WER=="mix")
varlist = c(varlist, "synchrones_file")
parallel::clusterExport(cl, varlist=varlist, envir = environment())
}
# 1000*K1 indices [if WER=="end"], or empty vector [if WER=="mix"] --> series on file
- if (parll)
+ if (parll && ntasks>1)
indices = unlist( parallel::parLapply(cl, indices_tasks, runTwoStepClustering) )
else
indices = unlist( lapply(indices_tasks, runTwoStepClustering) )
- if (parll)
+ if (parll && ntasks>1)
parallel::stopCluster(cl)
getRefSeries = getSeries
contribs_file, nb_series_per_chunk, nbytes, endian)
}
-
-
-#TODO: if ntasks==1, c'est deja terminé
-
# Run step2 on resulting indices or series (from file)
if (verbose)
cat("...Run final // stage 1 + stage 2\n")
indices_medoids = clusteringTask1(
indices, getContribs, K1, nb_series_per_chunk, ncores_tasks*ncores_clust, verbose, parll)
- medoids = computeClusters2(getSeries(indices_medoids), K2,
+ medoids1 = bigmemory::as.big.matrix( getSeries(indices_medoids) )
+ medoids2 = computeClusters2(medoids1, K2,
getRefSeries, nb_curves, nb_series_per_chunk, ncores_tasks*ncores_clust, verbose, parll)
# Cleanup
unlink(bin_dir, recursive=TRUE)
- medoids
+ medoids2
}
#' curvesToContribs