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sav08:evaluating_formulas_in_finite_structures [2008/03/18 19:12] vkuncak |
sav08:evaluating_formulas_in_finite_structures [2008/03/19 00:39] vkuncak |
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=== Example: Checking Database Integrity Constraint === | === Example: Checking Database Integrity Constraint === | ||
+ | |||
+ | Database integrity constraint: | ||
+ | ALL studentID. ALL courseID. Registered(studentID,courseID) --> (EX courseName. courseCatalog(courseID, courseName)) | ||
=== Example: Checking Assertion in Program with Heap === | === Example: Checking Assertion in Program with Heap === | ||
- | === Example: Checking Program Designs === | + | List contains no duplicates: |
+ | ALL n1. ALL n2. ListNode(n1) & ListNode(n2) & data(n1)=data(n2) --> n1=n2 | ||
+ | |||
===== Efficiency of Evaluating Formulas ===== | ===== Efficiency of Evaluating Formulas ===== | ||
+ | |||
+ | Given a language ${\cal L}$, formula a formula $F$ in ${\cal L}$ and an interpretation $I=(D,\alpha)$, determine $e_F(F)(I)$. | ||
+ | * fix formula: LOGSPACE (iterate over elements) | ||
+ | * fix language with symbols of bounded arity: PSPACE (reduce to [[QBF and Quantifier Elimination|QBF]]) | ||
+ | |||
+ | ===== References ===== | ||
* Neil Immerman: Descriptive Complexity | * Neil Immerman: Descriptive Complexity | ||