setcats

Set categories in categorical array

Syntax

B = setcats(A,newcats)

Description

B = setcats(A,newcats) sets categories in a categorical array. The output array B has the categories specified by newcats and elements that correspond to the elements of the input array A.

• If an element of A is in a category listed in newcats, then the corresponding element of B has the same value as in A.

• If A has a category not listed in newcats, then B does not have that category. The corresponding elements in B are undefined.

• If newcats lists a category that is not a category of A, then B has no elements equal to that category.

Examples

Set New Categories

Create a categorical array.

A = categorical(["blue" "black" "red" "red" "blue" "black" "black" "red" "blue"])

A = 1×9 categorical
     blue      black      red      red      blue      black      black      red      blue 

Set new categories. Elements that were blue in A are undefined in B.

B = setcats(A,["red" "black"])

B = 1×9 categorical
     <undefined>      black      red      red      <undefined>      black      black      red      <undefined> 

Set New Categories and Assign Elements

Create a categorical array.

A = categorical(["blue" "black" "red" "red" "blue" "black" "black" "red" "blue"])

A = 1×9 categorical
     blue      black      red      red      blue      black      black      red      blue 

Set new categories. Include a category that is not a category of A.

B = setcats(A,["red" "pink" "blue"])

B = 1×9 categorical
     blue      <undefined>      red      red      blue      <undefined>      <undefined>      red      blue 

No element of B is pink, because pink is not a category of A. Assign an element of B to be pink.

B(1) = "pink";
B

B = 1×9 categorical
     pink      <undefined>      red      red      blue      <undefined>      <undefined>      red      blue 

Input Arguments

A — Input array

categorical array

Input array, specified as a categorical array.

newcats — New categories

string array | character vector | cell array of character vectors

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

Tips

• To change category names in a categorical array, use renamecats.

Extended Capabilities

Tall Arrays

Calculate with arrays that have more rows than fit in memory.

The setcats function fully supports tall arrays. For more information, see Tall Arrays.

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Thread-Based Environment

Run code in the background using MATLAB® backgroundPool or accelerate code with Parallel Computing Toolbox™ ThreadPool.

This function fully supports thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.

Distributed Arrays

Partition large arrays across the combined memory of your cluster using Parallel Computing Toolbox™.

This function fully supports distributed arrays. For more information, see Run MATLAB Functions with Distributed Arrays (Parallel Computing Toolbox).

Version History

Introduced in R2014b