I have a matrix which represents the distances between every two relevant items. For example, M[i][j] holds the distance between items i and j. My next aim is to cluster items by these distances. I can provide some parameters: maximal number of clusters, maximal distance between two items in a cluster and minimal number of items in a cluster. I cannot, however, provide the "central items" which the algorithm should start with. I went through some of python's clustering packages, like scikit-learn, but did not find anything that matches.
Thank you :)