unique (MATLAB Function Reference)

Unique elements of a vector

Syntax

b = unique(a)
b = unique(A,'rows')
[b,i,j] = unique(...)

Description

b = unique(a) returns the same values as in a but with no repetitions. The resulting vector is sorted in ascending order. a can be a cell array of strings.

b = unique(A,'rows') returns the unique rows of A.

[b,i,j] = unique(...) also returns index vectors i and j such that b = a(i) and a = b(j). Each element of i is the greatest subscript such that b = a(i). For row combinations, b = a(i,:) and a = b(j,:).

Examples

a = [1 1 5 6 2 3 3 9 8 6 2 4]
a =
1     1     5     6     2     3     3     9     8     6     2     4

[b,i,j] = unique(a)
b =
      1     2     3     4     5     6     8     9
i =
      2    11     7    12     3    10     9     8
j =
1     1     5     6     2     3     3     8     7     6     2     4

a(i)
ans =
      1     2     3     4     5     6     8     9

b(j)
ans =
1     1     5     6     2     3     3     9     8     6     2     4

See Also

intersect, ismember, setdiff, setxor, union

union unix