major folder reorganisation, R pkg is now epclust/ at first level. Experimental usage...

[epclust.git] / epclust / R / algorithms.R

diff --git a/epclust/R/algorithms.R b/epclust/R/algorithms.R
new file mode 100644 (file)
index 0000000..97dce90
--- /dev/null
+++ b/epclust/R/algorithms.R
@@ -0,0 +1,24 @@
+#NOTE: always keep ID in first column
+curvesToCoeffs = function(series, wf)
+{
+       library(wavelets)
+       L = length(series[1,])
+       D = ceiling( log(L-1) )
+       nb_sample_points = 2^D
+       #TODO: parallel::parApply() ?!
+       res = apply(series, 1, function(x) {
+               interpolated_curve = spline(1:(L-1), x[2:L], n=nb_sample_points)$y
+               W = wavelets::dwt(interpolated_curve, filter=wf, D)@W
+               nrj_coeffs = rev( sapply( W, function(v) ( sqrt( sum(v^2) ) ) ) )
+               return ( c(x[1], nrj_coeffs) )
+       })
+       return (as.data.frame(res))
+}
+
+getClusters = function(data, K)
+{
+       library(cluster)
+       pam_output = cluster::pam(data, K)
+       return ( list( clusts=pam_output$clustering, medoids=pam_output$medoids,
+               ranks=pam_output$id.med ) )
+}