verify the correctness of "average silhouette width"

[zheng-da]

library(FlashR)
fm.set.conf("matrix/conf/run_test-EM.txt")
data <- fm.get.dense.matrix("pg-aug-selected.mat")
load("/mnt/nfs2/zhengda/pg-aug-24.vals")
svals <- sqrt(vals[1:14])
data <- fm.mapply.row(data, sqrt(c(svals, svals)), "*")
data <- fm.conv.store(data, in.mem=TRUE)
fm.set.test.na(FALSE)
for (k in seq(2, 64, 2)) {
res <- fm.kmeans(data, centers=k, iter.max=100)
print(paste("K=", k, ", silhouette=", as.vector(mean(kmeans.silhouette(res, data))), sep=""))
}