Fix unit tests
[epclust.git] / epclust / R / clustering.R
index fce1b1c..493f90f 100644 (file)
@@ -2,16 +2,24 @@
 clusteringTask = function(indices, getCoefs, K1, nb_series_per_chunk, ncores)
 {
        cl = parallel::makeCluster(ncores)
+       parallel::clusterExport(cl, varlist=c("getCoefs","K1"), envir=environment())
        repeat
        {
-               nb_workers = max( 1, round( length(indices) / nb_series_per_chunk ) )
-               indices_workers = lapply(seq_len(nb_workers), function(i) {
-                       upper_bound = ifelse( i<nb_workers,
-                               min(nb_series_per_chunk*i,length(indices)), length(indices) )
-                       indices[(nb_series_per_chunk*(i-1)+1):upper_bound]
-               })
-               indices = unlist( parallel::parLapply(cl, indices_workers, function(inds)
-                       computeClusters1(getCoefs(inds), K1)) )
+               nb_workers = max( 1, floor( length(indices) / nb_series_per_chunk ) )
+               indices_workers = lapply( seq_len(nb_workers), function(i)
+                       indices[(nb_series_per_chunk*(i-1)+1):(nb_series_per_chunk*i)] )
+               # Spread the remaining load among the workers
+               rem = length(indices) %% nb_series_per_chunk
+               while (rem > 0)
+               {
+                       index = rem%%nb_workers + 1
+                       indices_workers[[index]] = c(indices_workers[[index]], tail(indices,rem))
+                       rem = rem - 1
+               }
+               indices = unlist( parallel::parLapply( cl, indices_workers, function(inds) {
+                       require("epclust", quietly=TRUE)
+                       inds[ computeClusters1(getCoefs(inds), K1) ]
+               } ) )
                if (length(indices) == K1)
                        break
        }
@@ -21,20 +29,18 @@ clusteringTask = function(indices, getCoefs, K1, nb_series_per_chunk, ncores)
 
 # Apply the clustering algorithm (PAM) on a coeffs or distances matrix
 computeClusters1 = function(coefs, K1)
-       indices[ cluster::pam(coefs, K1, diss=FALSE)$id.med ]
+       cluster::pam(coefs, K1, diss=FALSE)$id.med
 
 # Cluster a chunk of series inside one task (~max nb_series_per_chunk)
 computeClusters2 = function(medoids, K2, getRefSeries, nb_series_per_chunk)
 {
        synchrones = computeSynchrones(medoids, getRefSeries, nb_series_per_chunk)
-       cluster::pam(computeWerDists(synchrones), K2, diss=TRUE)$medoids
+       medoids[ cluster::pam(computeWerDists(synchrones), K2, diss=TRUE)$medoids , ]
 }
 
 # Compute the synchrones curves (sum of clusters elements) from a clustering result
 computeSynchrones = function(medoids, getRefSeries, nb_series_per_chunk)
 {
-       #les getSeries(indices) sont les medoides --> init vect nul pour chacun, puis incr avec les
-       #courbes (getSeriesForSynchrones) les plus proches... --> au sens de la norme L2 ?
        K = nrow(medoids)
        synchrones = matrix(0, nrow=K, ncol=ncol(medoids))
        counts = rep(0,K)
@@ -48,18 +54,20 @@ computeSynchrones = function(medoids, getRefSeries, nb_series_per_chunk)
                #get medoids indices for this chunk of series
                for (i in seq_len(nrow(ref_series)))
                {
-                       j = which.min( rowSums( sweep(medoids, 2, series[i,], '-')^2 ) )
-                       synchrones[j,] = synchrones[j,] + series[i,]
+                       j = which.min( rowSums( sweep(medoids, 2, ref_series[i,], '-')^2 ) )
+                       synchrones[j,] = synchrones[j,] + ref_series[i,]
                        counts[j] = counts[j] + 1
                }
                index = index + nb_series_per_chunk
        }
        #NOTE: odds for some clusters to be empty? (when series already come from stage 2)
-       sweep(synchrones, 1, counts, '/')
+       #      ...maybe; but let's hope resulting K1' be still quite bigger than K2
+       synchrones = sweep(synchrones, 1, counts, '/')
+       synchrones[ sapply(seq_len(K), function(i) all(!is.nan(synchrones[i,]))) , ]
 }
 
 # Compute the WER distance between the synchrones curves (in rows)
-computeWerDist = function(curves)
+computeWerDists = function(curves)
 {
        if (!require("Rwave", quietly=TRUE))
                stop("Unable to load Rwave library")