Categorical Arrays - MATLAB & Simulink (original) (raw)

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Arrays of qualitative data with values from a finite set of discrete, nonnumeric data

categorical is a data type to store data with values from a finite set of discrete categories. For example, the syntax C = categorical({'R','G','B','B','G','B'}) creates a categorical array with six elements that belong to the categories R,G, or B.

A categorical array provides efficient storage and convenient manipulation of nonnumeric data, while also maintaining meaningful names for the data values. The categories can have a natural order, but it is not required. For more information see Create Categorical Arrays or watch Tables and Categorical Arrays.

Functions

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categories	List of categories in categorical array
iscategorical	Determine if input is categorical array
iscategory	Determine if inputs are names of categories
isordinal	Determine if input is ordinal categorical array
isprotected	Determine if categories of categorical array are protected
isundefined	Find undefined elements in categorical array

addcats	Add categories to categorical array
mergecats	Merge categories in categorical array
removecats	Remove categories from categorical array
renamecats	Rename categories in categorical array
reordercats	Reorder categories in categorical array
setcats	Set categories in categorical array
combinations	Generate all element combinations of arrays (Since R2023a)

summary	Data summary
countcats	Count occurrences of categorical array elements by category

Topics

Create Categorical Arrays
Create categorical arrays from various types of input data and modify their elements.
Access Data Using Categorical Arrays
Search, select, and delete elements from categorical arrays.
Advantages of Using Categorical Arrays
Categorical arrays provide a natural representation of data, mathematical ordering of character vectors, and efficient memory usage.
Core Functions Supporting Categorical Arrays
Many functions in MATLAB® operate on categorical arrays in much the same way that they operate on other arrays. A few of these functions might exhibit special behavior when operating on a categorical array.