Some questions regarding hierarchical clusters

I would like to know how to perform some operations on a hierarchical cluster:

for a given additional point not included in the cluster, its distance to the closest centroids for each depth in the cluster hierarchy *for a given leaf, know its linkage distance to the other leafs it is linked too, up the hierarchy *prune a single leaf from the dendrogram (which *should be different from clustering without that element)

Any hints would be greatly welcome. josep

[Walter Roberson]

replaced by http://uk.mathworks.com/matlabcentral/answers/248421-some-questions-regarding-hierarchical-clusters