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Union ()

Union[list1, list2, ...]
gives a sorted list of all the distinct elements that appear in any of the listi.
Union[list]
gives a sorted version of a list, in which all duplicated elements have been dropped.
  • If the listi are considered as sets, Union gives their union.
  • The listi must have the same head, but it need not be List.
  • Union[list1, ..., SameTest->test] applies test to each pair of elements in the listi to determine whether they should be considered the same.
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