%% Reorder Categories in Nonordinal Categorical Array
% Create a categorical array containing the color of various items.

A = categorical({'red';'green';'blue';'red';'green';'red';'blue';'blue'})

% A is an 8-by-1 categorical array.
%
% Display the categories of A.

categories(A)

% The categories of A are in alphabetical order and have no mathematical meaning.
%
% Reorder the categories to match the order commonly used for colors.

B = reordercats(A,{'red','green','blue'})

% B contains the same values as A.
%
% Display the categories of B.

categories(B)

% B is not ordinal and the order of the categories has no mathematical meaning. Although the categories appear in the order of the color spectrum, relational operations, such as greater than and less than, have no meaning.
% Copyright 2012 The MathWorks, Inc.