24. The method of claim 20, for performing an exact search, comprising the steps of: associating specified data to one of the clusters based on stored clustering information; decomposing the specified data into a reduced dimensionality cluster defined by an associated cluster and stored dimensionality reduction information for the associated cluster, in response to said associating; and searching for a matching reduced dimensionality cluster based on decomposed specified data.
24. The method of claim 20, for performing an exact search, comprising the steps of: associating specified data to one of the clusters based on stored clustering information; decomposing the specified data into a reduced dimensionality cluster defined by an associated cluster and stored dimensionality reduction information for the associated cluster, in response to said associating; and searching for a matching reduced dimensionality cluster based on decomposed specified data. 25. The method of claim 24, wherein the specified data includes a search template, further comprising the steps of: said associating comprising identifying the search template with a cluster based on the stored clustering information; said decomposing comprising projecting the search template onto a subspace for an identified cluster based on the stored dimensionality reduction information; and said searching comprising performing an intra-cluster search for a projected template.