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Union ()

Union[list₁, list₂, ...]
gives a sorted list of all the distinct elements that appear in any of the list_i.

Union[list]
gives a sorted version of a list, in which all duplicated elements have been dropped.

MORE INFORMATION

If the list_i are considered as sets, Union gives their union.

Union[list₁, list₂, ...] can be input in StandardForm and InputForm as list₁list₂.... The character can be entered as Esc un Esc or \[Union].

The list_i must have the same head, but it need not be List.

Union[list₁, ..., SameTest->test] applies test to each pair of elements in the list_i to determine whether they should be considered the same.

Basic Examples (3)

Give a sorted list of distinct elements:

Give a sorted list of distinct elements from all the lists:

Enter using Esc un Esc:

Generalizations & Extensions (1)

Applications (4)

Properties & Relations (2)

Possible Issues (1)

Join Intersection Complement Tally DeleteDuplicates BinLists Split Or BitOr

Combining Lists

Lists as Sets

Exploratory Data Analysis

Discrete & Integer Data

Discrete Mathematics

Handling Arrays of Data

Math & Counting Operations on Lists

Numerical Data

Rearranging & Restructuring Lists

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