DuplicateFreeQ

DuplicateFreeQ[list]
gives True if list has no duplicates, and False otherwise.

DuplicateFreeQ[list,test]
applies test to pairs of elements to determine whether they should be considered duplicates.

DetailsDetails

ExamplesExamplesopen allclose all

Basic Examples  (1)Basic Examples  (1)

Determine whether or not the list has duplicated elements:

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Use Tally to reveal duplicate elements:

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Introduced in 2014
(10.0)