Pattern Description and Recognition in Formal Language

In dealing with a complicated pattern it is essential to analyse the pattern into subpatterns, to which some information measure is to be assigned. According to this information measure which is generated by a certain mechanism, it is decided whether the corresponding sub-pattern is not worth being maintained for further processing or how detailed it should be described or how it should be transformed. The mechanism which generates the information measures to be assigned to the subpatterns functions depending upon the mission for which the given pattern is being processed.