In computer science, a rough set, first described by a Polish computer scientist Zdzisław I. Pawlak, is a formal approximation of a crisp set (i.e., conventional set) in terms of a pair of sets which give the lower and the upper approximation of the original set. In the standard version of rough set theory (Pawlak 1991), the lower- and upper-approximation sets are crisp sets, but in other variations, the approximating sets may be fuzzy sets.
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Famous quotes containing the words rough and/or set:
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Which he than man more harmless found and mild.”
—William Drummond, of Hawthornden (1585–1649)
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—Simone Weil (1909–1943)