Minimum matrix representation of closure operations
نویسندگان
چکیده
Let (I be a column of the fft x /I matrix M and A a set of its columns. We say that A implies a iff M contains no two rows equal in A but different in a. It is easy IO see that if Y,~,(A) denotes . the columns implied by A, than :/,,,(A) is a closure operation. We say that M represents this closure operation. s(:/ ) is the minimum number of the rows of the matrices representing a given closure operation. s(? ) is determined for some particular closure operations.
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 11 شماره
صفحات -
تاریخ انتشار 1985