8
$\begingroup$

Currently I made some slides to illustrate clustering. As an example I made a point set of two clusters:

   {clusters, graph} = Block[{c1, c2, cluster1, cluster2},
   c1 = {1, 2}; 
   cluster1 = (# + c1) & /@ 
     RandomVariate[NormalDistribution[0, 0.5], {10^3, 2}];
   c2 = {3, 3}; 
   cluster2 = (# + c2) & /@ 
     RandomVariate[NormalDistribution[0, 0.5], {10^3, 2}];
   {clusters = Union[cluster1, cluster2],
    Graphics[{{Green, Point[cluster1]}, {Red, Point[cluster2]}}, 
     Frame -> True]}
   ];
graph

which looks somewhat like:

enter image description here

Mathematica is a powerful tool, so I tried a naive approach

cls = FindClusters[clusters];

... and got:

enter image description here

Further "experiments" like

FindClusters[clusters, DistanceFunction -> EuclideanDistance]

were all not successful. What worked immediately is

FindClusters[clusters, Method -> "Optimize"]

which delivers:

enter image description here

But the method "Optimize" is removed from documentation, see Question addressing FindClusters

So the question is: Is there an easy way to find the (obvious) clusters in that case without putting parts of the "solution" (two clusters) in the options of FindClusters?

$\endgroup$

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.