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Categorical Arrays

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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categoricalArray that contains values assigned to categories
discretizeGroup data into bins or categories
categoriesCategories of categorical array
iscategoricalDetermine whether input is categorical array
iscategoryTest for categorical array categories
isordinalDetermine whether input is ordinal categorical array
isprotectedDetermine whether categories of categorical array are protected
isundefinedFind undefined elements in categorical array
addcatsAdd categories to categorical array
mergecatsMerge categories in categorical array
removecatsRemove categories from categorical array
renamecatsRename categories in categorical array
reordercatsReorder categories in categorical array
setcatsSet categories in categorical array
summaryPrint summary of table, timetable, or categorical array
countcatsCount occurrences of categorical array elements by category

Topics

Create Categorical Arrays

This example shows how to create a categorical array.

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.