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+@c Copyright (C) 1996, 1997 John W. Eaton
+@c This is part of the Octave manual.
+@c For copying conditions, see the file gpl.texi.
+
+@node Sets, Polynomial Manipulations, Statistics, Top
+@chapter Sets
+
+Octave has a limited set of functions for managing sets of data, where a
+set is defined as a collection unique elements.
+
+@deftypefn {Function File} {} create_set (@var{x})
+Return a row vector containing the unique values in @var{x}, sorted in
+ascending order.  For example,
+
+@example
+@group
+create_set ([ 1, 2; 3, 4; 4, 2 ])
+     @result{} [ 1, 2, 3, 4 ]
+@end group
+@end example
+@end deftypefn
+
+@deftypefn {Function File} {} union (@var{x}, @var{y})
+Return the set of elements that are in either of the sets @var{x} and
+@var{y}.  For example,
+
+@example
+@group
+union ([ 1, 2, 4 ], [ 2, 3, 5 ])
+     @result{} [ 1, 2, 3, 4, 5 ]
+@end group
+@end example
+@end deftypefn
+
+@deftypefn {Function File} {} intersection (@var{x}, @var{y})
+Return the set of elements that are in both sets @var{x} and @var{y}.
+For example,
+
+@example
+@group
+intersection ([ 1, 2, 3 ], [ 2, 3, 5 ])
+     @result{} [ 2, 3 ]
+@end group
+@end example
+@end deftypefn
+
+@deftypefn {Function File} {} complement (@var{x}, @var{y})
+Return the elements of set @var{y} that are not in set @var{x}.  For
+example,
+
+@example
+@group
+complement ([ 1, 2, 3 ], [ 2, 3, 5 ])
+     @result{} 5
+@end group
+@end example
+@end deftypefn