The point samples are arranged in a hierarchic data structure in a manner such that each point sample is {TAIL ~ an end point}, or {HEAD ~ leaf node}, in a hierarchical tree, wherein the branch points in the hierarchy tree are average values of the nodes lower in the hierarchy of the tree 
The point samples are arranged in a hierarchic data structure in a manner such that each point sample is { TAIL ~ an end point } , or { HEAD ~ leaf node } , in a hierarchical tree , wherein the branch points in the hierarchy tree are average values of the nodes lower in the hierarchy of the tree
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH