Stable Models
The definition of a stable model below, reproduced from, uses two conventions. First, a truth assignment is identified with the set of atoms that get the value T. For instance, the truth assignment
|
|
|
|
|
is identified with the set . This convention allows us to use the set inclusion relation to compare truth assignments with each other. The smallest of all truth assignments is the one that makes every atom false; the largest truth assignment makes every atom true.
Second, a logic program with variables is viewed as shorthand for the set of all ground instances of its rules, that is, for the result of substituting variable-free terms for variables in the rules of the program in all possible ways. For instance, the logic programming definition of even numbers
is understood as the result of replacing in this program by the ground terms
in all possible ways. The result is the infinite ground program
Read more about this topic: Stable Model Semantics
Famous quotes containing the words stable and/or models:
“In short, no association or alliance can be happy or stable without me. People can’t long tolerate a ruler, nor can a master his servant, a maid her mistress, a teacher his pupil, a friend his friend nor a wife her husband, a landlord his tenant, a soldier his comrade nor a party-goer his companion, unless they sometimes have illusions about each other, make use of flattery, and have the sense to turn a blind eye and sweeten life for themselves with the honey of folly.”
—Desiderius Erasmus (c. 1466–1536)
“Friends broaden our horizons. They serve as new models with whom we can identify. They allow us to be ourselves—and accept us that way. They enhance our self-esteem because they think we’re okay, because we matter to them. And because they matter to us—for various reasons, at various levels of intensity—they enrich the quality of our emotional life.”
—Judith Viorst (20th century)