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sav08:evaluating_formulas_in_finite_structures [2008/03/19 00:46] vkuncak |
sav08:evaluating_formulas_in_finite_structures [2008/03/19 15:23] vkuncak |
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| Given a language ${\cal L}$, formula a formula $F$ in ${\cal L}$ and an interpretation $I=(D,\alpha)$, determine $e_F(F)(I)$. | 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]]) | + | Basic idea: to evaluate quantifiers, iterate over all domain elements. |
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| + | * fix formula, change domain size $|D|$: LOGSPACE (number of vars fixed, number of their bits changes) | ||
| + | * fix language with symbols of bounded arity, change formula: PSPACE (number of variables increases with formula size, see also [[QBF and Quantifier Elimination|QBF]]) | ||
| ===== References ===== | ===== References ===== | ||