1. A pattern recognition apparatus, said apparatus comprising: memory means for storing a plurality of reference patterns for each category of a predetermined set of patterns, said reference patterns being orthnormalized with respect to each other; input vector generating means for generating an input vector by extracting a feature from an unknown input pattern; basis generating means coupled to said input vector generating means for generating a plurality of bases by deforming said input vector, said bases being orthonormalized with respect to each other; matrix producing means coupled to said memory means and said bases generating means for producing a matrix for each category of said set of patterns, said matrix being formed from a plurality of data elements derived from said bases generated by said basis generating means and from said reference patterns stored in said memory means; and determining means coupled to said matrix producing means for analyzing each of said matrixes to determine the category to which said input pattern belongs.