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DOCUMENTATION CENTER SEARCH
New to
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Find your learning path
»
Mathematica
>
Core Language
>
List Manipulation
>
Rearranging & Restructuring Lists
>
DeleteDuplicates
>
Mathematica
>
Data Manipulation
>
Handling Arrays of Data
>
Rearranging & Restructuring Lists
>
DeleteDuplicates
>
Mathematica
>
Data Manipulation
>
Image Processing & Analysis
>
Basic Image Manipulation
>
Handling Arrays of Data
>
Rearranging & Restructuring Lists
>
DeleteDuplicates
>
BUILT-IN MATHEMATICA SYMBOL
Union
Tally
DeleteCases
Select
Gather
Split
Partition
See Also »
|
Elements of Lists
List Manipulation
Rearranging & Restructuring Lists
Summary of New Features in 7.0
New in 7.0: Alphabetical Listing
New in 7.0: Core Language
New in 7.0: Lists and Matrices
More About »
DeleteDuplicates
DeleteDuplicates
[
list
]
deletes all duplicates from
list
.
DeleteDuplicates
applies
test
to pairs of elements to determine whether they should be considered duplicates.
MORE INFORMATION
DeleteDuplicates
[
list
]
deletes all but the first occurrence of each distinct element that appears in
list
.
DeleteDuplicates
never reorders elements, but only removes them.
DeleteDuplicates
[
list
]
is equivalent to
DeleteDuplicates
[
list
,
SameQ
]
.
EXAMPLES
CLOSE ALL
Basic Examples
(1)
Delete duplicated elements:
Delete duplicated elements:
In[1]:=
Out[1]=
Scope
(1)
Delete sublists that have the same total:
Properties & Relations
(1)
DeleteDuplicates
is similar to
Union
without sorting:
Avoiding the sort improves the speed substantially:
SEE ALSO
Union
Tally
DeleteCases
Select
Gather
Split
Partition
MORE ABOUT
Elements of Lists
List Manipulation
Rearranging & Restructuring Lists
Summary of New Features in 7.0
New in 7.0: Alphabetical Listing
New in 7.0: Core Language
New in 7.0: Lists and Matrices
New in 7
EXAMPLES
Basic Examples 
Scope 