Clustering data sets into unknown number of groups

如何把三維的點集合進行分類，但是幾類是未知的？

Surfing online...

1. 漫谈 Clustering (5): Hierarchical Clustering  http://blog.pluskid.org/?p=407
2. Cluster analysis  http://en.wikipedia.org/wiki/Cluster_analysis
3. Unsupervised Learning — Clustering Analysis  http://c3h3notes.wordpress.com/2010/10/29/unsupervised-learning-clustering-analysis/
4. Unsupervised clustering with unknown number of clusters   http://stackoverflow.com/questions/10136470/unsupervised-clustering-with-unknown-number-of-clusters
5. Hierarchical Clustering與K-Means Clustering   http://sls.weco.net/blog/chang/14-nov-2008/11503
6. Hierarchical clustering algorithm   https://sites.google.com/site/dataclusteringalgorithms/hierarchical-clustering-algorithm
7. Hierarchical clustering using C++   http://blog.o-x-t.com/2009/01/23/hierarchical_clustering/
8. HIERARCHICAL CLUSTERING ALGORITHMS   http://cgm.cs.mcgill.ca/~soss/cs644/projects/siourbas/sect5.html
9. C/C++ Machine Learning Libraries for Clustering   http://stackoverflow.com/questions/815423/c-c-machine-learning-libraries-for-clustering
10. Agglomerative Clustering?   http://itk-insight-users.2283740.n2.nabble.com/Agglomerative-Clustering-td3342283.html
11. hierarchical clustering using flann in opencv   http://stackoverflow.com/questions/15549001/hierarchical-clustering-using-flann-in-opencv
12. Hierarchical k-Means in OpenCV without knowledge of “k”   http://stackoverflow.com/questions/5461357/hierarchical-k-means-in-opencv-without-knowledge-of-k

Lots of algorithm/solution can be googled....I think the most appropriate is ---> Hierarchical clustering