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A New Differencing Operation for Multiple Output Functions

IP.com Disclosure Number: IPCOM000070280D
Original Publication Date: 1978-Aug-01
Included in the Prior Art Database: 2005-Feb-21

Publishing Venue

IBM

Related People

Authors:
Junker, LV Roth, JP [+details]

Abstract

In the minimization of multiple-output 2-level logic, also programmed logic arrays, a differencing operation among cubes, called the #-product (pronounced "sharp product"), is used to considerable advantage [1, 4]. Given two cubes or two covers of cubes, the #-product finds a cover of the vertices of the first which is not in the second. It is used in the formation of the prime cubes (implicants, for the case of one output). It is also used in the LESS-THAN operation in the extraction algorithm. In the old #-product, the cubes produced were in general not disjoint, and this was most inconvenient in attempting to count the vertices of the resulting cover. This counting operation was used in the extraction algorithm, but it has also been used to advantage in statistical operations [3]. The new "sharp product.