MATLAB Programming Fundamentals - MathWorks

D = 1x3 categorical array

+ blue - red + green

categories(D)

ans = 6x1 cell array

{'+ blue' }

{'+ green'}

{'+ red' }

{'- blue' }

{'- green'}

{'- red' }

Multiplication with Undefined Elements

Combine two categorical arrays. If either A or B have an undefined element, the

corresponding element of C is undefined.

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

B = categorical({'+','-','+','-'});

A = removecats(A,{'black'});

C = A.*B

C = 1x4 categorical array

blue + red - green + <undefined>

Cartesian Product of Ordinal Categorical Arrays

Combine two ordinal categorical arrays. C is an ordinal categorical array only if A and B

are both ordinal. The ordering of the categories of C follows from the orderings of the

input categorical arrays.

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

B = categorical({'+','-','+'},'Ordinal',true);

C = A.*B;

categories(C)

ans = 6x1 cell array

{'green +'}

{'green -'}

{'red +' }

{'red -' }

8 Categorical Arrays