implementing my clusterer

[ElemenT5ven]

Hello, I'm new here, and I'm trying to implement a BDSCAN algo for clustering string and date type attributes.

I overided buildClusterer(), numberOfClusters(), clusterInstance() and getCapabilities().
I stored into a hashmap<Instance, Integer> to know which cluster every Instance is attributed to so I can call it in clusterInstance().
I still don't know what correspond the prior probability of clusterPriors() and everything about logDensityPerClusterForInstance(), so left it as return null but I tried to hardcode it also but it doesn't change my issue.

So when I'm running my code, I got this:
=== Clustering stats for training data ===
Clustered Instances
Unclustered Instances : 1799
Log likelihood: NaN