Engineering↗
Class Operators H, S, P and the Definition of a Variety
The class operators I, S, H, P and P_S, the inclusions and idempotency relations among their composites, and the identification of HSP as the variety-generating closure operator.
Every page in the KEVOS library tagged closure operator. 3 pages.
The class operators I, S, H, P and P_S, the inclusions and idempotency relations among their composites, and the identification of HSP as the variety-generating closure operator.
Closure operators and closure systems, the correspondence with complete lattices, the finitary case and algebraic lattices, and Galois connections as the standard source of clos…
Subuniverses, subalgebras, the generation operator Sg(X), and the two equivalent descriptions of generation as intersection from above and as term-closure from below.