MyWikiBiz, Author Your Legacy — Tuesday November 26, 2024
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, 03:00, 7 January 2013
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| Suppose <math>L \subseteq X \times Y \times Z\!</math> is an arbitrary triadic relation and consider the information about <math>L\!</math> that is provided by collecting its dyadic projections. To formalize this information define the ''projective triple'' of <math>L\!</math> as follows: | | Suppose <math>L \subseteq X \times Y \times Z\!</math> is an arbitrary triadic relation and consider the information about <math>L\!</math> that is provided by collecting its dyadic projections. To formalize this information define the ''projective triple'' of <math>L\!</math> as follows: |
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| + | {| align="center" cellspacing="8" width="90%" |
| + | | <math>\operatorname{Proj}^{(2)}(L) ~=~ (\operatorname{proj}_{12}(L), \operatorname{proj}_{13}(L), \operatorname{proj}_{23}(L)).</math> |
| + | |} |
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| <pre> | | <pre> |
− | Proj (R) = Pr2(R) = <Pr12(R), Pr13(R), Pr23(R)>.
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| If R is visualized as a solid body in the 3 dimensional space XxYxZ, then Proj (R) can be visualized as the arrangement or ordered collection of shadows it throws on the XY, XZ, and YZ planes, respectively. | | If R is visualized as a solid body in the 3 dimensional space XxYxZ, then Proj (R) can be visualized as the arrangement or ordered collection of shadows it throws on the XY, XZ, and YZ planes, respectively. |
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