## Description

example

B = addcats(A,newcats) adds categories to the end of the category list for the input categorical array, A. The output categorical array, B, contains the same values as A. The output, B, does not contain any elements equal to the new categories until you assign values from newcats to elements in B.

If A is an ordinal categorical array, you must specify the 'Before',beforewhere or 'After',afterwhere input arguments.

example

## Examples

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Create a nonordinal categorical array.

A = categorical({'republican' 'democrat' 'republican';...
'democrat' 'republican' 'democrat'})
A = 2x3 categorical
republican      democrat        republican
democrat        republican      democrat

Display the categories of A.

categories(A)
ans = 2x1 cell
{'democrat'  }
{'republican'}

A is a 2-by-3 categorical array with two categories.

Add the categories, independent and undeclared, to the end of the category list.

B = 2x3 categorical
republican      democrat        republican
democrat        republican      democrat

B contains the same values as A.

Display the categories of B.

categories(B)
ans = 4x1 cell
{'democrat'   }
{'republican' }
{'independent'}
{'undeclared' }

B is a 2-by-3 categorical array with four categories.

Create an ordinal categorical array.

A = categorical({'medium' 'large'; 'small' 'xlarge'; 'large' 'medium'},...
{'small' 'medium' 'large' 'xlarge'},'Ordinal',true)
A = 3x2 categorical
medium      large
small       xlarge
large       medium

Display the categories of A.

categories(A)
ans = 4x1 cell
{'small' }
{'medium'}
{'large' }
{'xlarge'}

Since A is ordinal, the categories have the mathematical ordering small < medium < large < xlarge.

Add the category xsmall before small.

B = 3x2 categorical
medium      large
small       xlarge
large       medium

B contains the same values as A.

Display the categories of B.

categories(B)
ans = 5x1 cell
{'xsmall'}
{'small' }
{'medium'}
{'large' }
{'xlarge'}

The categories have the mathematical ordering xsmall < small < medium < large < xlarge.

## Input Arguments

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Categorical array, specified as a vector, matrix, or multidimensional array.

New categories, specified as a character vector, a cell array of character vectors, or a string array.

Category to precede, specified as a character vector or a string scalar.

Category to follow, specified as a character vector or a string scalar.

## Version History

Introduced in R2013b