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Map Containers

Objects with keys that index to values, where keys need not be integers

Store data values in a Map object, which is a data structure that associates each value with a corresponding key. A Map object is similar to a dictionary or associative array in that you can use keys to retrieve values from it. Keys can be numbers or text, providing more flexibility for data access than array indices.


containers.MapObject that maps values to unique keys
isKeyDetermine if Map object contains key
keysReturn keys of Map object
removeDelete key-value pairs from Map object
valuesReturn values of Map object


Overview of Map Data Structure

A Map is a type of fast key lookup data structure that offers a flexible means of indexing into its individual elements. The indices for a Map can be nearly any scalar numeric value or a character vector.

Description of Map Class

A Map is an object, or instance, of the containers.Map class.

Create Map Object

Create a Map using the containers.Map class.

Examine Contents of Map

This example shows how to find all the keys and values in a Map.

Read and Write Using Key Index

This example shows how to read from a Map structure and how to add new key/value pairs.

Modify Keys and Values in Map

This example shows how to remove and modify keys and values in a Map structure.

Map to Different Value Types

This example shows how to store structures or cell arrays in a Map structure.