Abstract
CLEF is a Java library implementing some of the literature algorithms for logical relationship extraction from conceptual structures. The library allows to process multivalued contexts with pattern structures and to automatically build a meet semi-lattice of patterns representing the similarities between objects having non-binary descriptions. The library is generic enough to extend it with (1) new extraction algorithms based on (2) different types of conceptual structures, and (3) new automated or semi-automated methods to build meet semi-lattices of patterns.