Method for using isometries on the space of signatures to find similar sets of data

A method for finding sets of data (SDDs) which are similar to a target SDD, is invented. By virtue of the isometrics on the space of equivalence signatures the lengths of the equivalence signature vectors of similar SDDs must be equal. A filter is then applied to the database of SDDs to find those SDDs that have the same length of the equivalence signatures vectors as that of the target SDD. With this, a significant reduction in the number of SDDs to be compared with the target for a final determination of similarity is obtained. This is an improvement over the state of the art wherein the computational expensive process of performing a complete search against the entire corpus must be applied.