Definition: (1) Of a boolean, 0 if 1, or 1 if 0. See not. (2) Of a set A, a set having all the members which are in the universe, but not in A.

See also difference, union, intersection.

Note: The complement can be seen as the difference of a set and the universe, or the universal set. That is, A' = U - A. If the universe is {1, 2, 3, 4}, then the complement of {1, 2} is {3, 4}, and the complement of {3} is {1, 2, 4}.

Author: PEB

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Entry modified 17 December 2004.
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Cite this as:
Paul E. Black, "complement", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed., U.S. National Institute of Standards and Technology. 17 December 2004. (accessed TODAY) Available from:

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