MyWikiBiz, Author Your Legacy — Tuesday November 19, 2024
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, 02:48, 19 March 2009
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− | This means that the propositional program itself is nothing more or less than a single proposition or boolean function <math>p : \mathbb{B}^{57} \to \mathbb{B}.</math> | + | This means that the propositional program itself is nothing but a single proposition or boolean function of the form <math>p : \mathbb{B}^{57} \to \mathbb{B}.</math> |
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− | <pre>
| + | An assignment of boolean values to the above set of boolean variables is called an ''interpretation'' of the proposition <math>p,\!</math> and any interpretation of <math>p\!</math> that makes the proposition <math>p : \mathbb{B}^{57} \to \mathbb{B}</math> evaluate to <math>1\!</math> is referred to as a ''satisfying interpretation'' of the proposition <math>p.\!</math> Another way to specify interpretations, instead of giving them as bit vectors in <math>\mathbb{B}^{57}</math> and trying to remember some arbitrary ordering of variables, is to give them in the form of ''singular propositions'', that is, a conjunction of the form <math>e_1 \cdot \ldots \cdot e_{57}</math> where each <math>e_j\!</math> is either <math>v_j\!</math> or <math>\texttt{(} v_j \texttt{)},</math> that is, either the assertion or the negation of the boolean variable <math>v_j,\!</math> as <math>j\!</math> runs from 1 to 57. Even more briefly, the same information can be communicated simply by giving the conjunction of the asserted variables, with the understanding that each of the others is negated. |
− | An assignment of boolean values to the above set of boolean variables | |
− | is called an "interpretation" of P, and any interpretation of P that | |
− | makes the proposition P : B^57 -> B evaluate to 1 is referred to as | |
− | a "satisfying interpretation" of the proposition P. Another way to | |
− | specify interpretations, instead of giving them as bit vectors in | |
− | B^57 and trying to remember some arbitrary ordering of variables, | |
− | is to give them in the form of "singular propositions", that is, | |
− | a conjunction of the form "e_1 & ... & e_57" where each e_j is | |
− | either "v_j" or "(v_j)", that is, either the assertion or the | |
− | negation of the boolean variable v_j, as j runs from 1 to 57. | |
− | Even more briefly, the same information can be communicated | |
− | simply by giving the conjunction of the asserted variables, | |
− | with the understanding that each of the others is negated. | |
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− | A satisfying interpretation of the proposition P supplies us | + | A satisfying interpretation of the proposition <math>p\!</math> supplies us with all the information of a complete execution history for the corresponding program, and so all we have to do in order to get the output of the program <math>p\!</math> is to read off the proper part of the data from the expression of this interpretation. |
− | with all the information of a complete execution history for | |
− | the corresponding program, and so all we have to do in order | |
− | to get the output of the program P is to read off the proper | |
− | part of the data from the expression of this interpretation. | |
− | </pre>
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| ===Output=== | | ===Output=== |