unique - Class: categorical

Unique values in categorical array

Note   In a future release, the behavior of categorical.unique will change to be consistent with the MATLAB function unique. This behavior change is optional in R2012a. For a demonstration of using the 'R2012a' flag to preview the future behavior, or the 'legacy' flag to preserve the current behavior in your existing code, see the documentation for unique.

Syntax

Description

C = unique(A) returns a categorical array containing the same values as in A but with no repetitions. C is sorted by the order of A's levels.

[C,IA,IC] = unique(A) also returns index vectors IA and IC such that C = A(IA) and A = C(IC).

[...] = unique(A,'rows') for the categorical matrix A returns the unique rows of A. The rows of the matrix C are sorted by the order of A's levels. The optional outputs IA and IC are index vectors such that C = A(IA,:) and A = C(IC,:).

[...] = unique(A,occurrence) and [...] = unique(A,'rows',occurrence) specify which index is returned in IA in the case of repeated values or rows in A. The default value is occurrence='last', which returns the index of the last occurrence of each repeated value or row in A. occurrence='first' returns the index of the first occurrence of each repeated value or row in A.

[...] = unique(...,'R2012a') adopts the future behavior of unique. You can specify the flag as the final argument with any previous syntax that accepts A, 'rows', or occurrence.

[...] = unique(...,'legacy') preserves the current behavior of unique. You can specify the flag as the final argument with any previous syntax that accepts A, 'rows', or occurrence.

[...] = unique(A,setOrder) and [...] = unique(A,'rows',setOrder) returns the values or rows of C in a specific order. setOrder='sorted' returns the values or rows of C in sorted order. setOrder='stable' returns the values or rows of C in the same order as A. If A is a row vector, then C is also a row vector. Otherwise, C is a column vector. IA and IC are column vectors. If there are repeated values in A, then IA returns the index of the first occurrence of each repeated value.

See Also

intersect | ismember | setdiff | setxor | union