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Map Containers

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

Store data values in aMapobject, which is a data structure that associates each value with a corresponding key. AMapobject 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.

Functions

containers.Map Object that maps values to unique keys
isKey Determine ifMapobject contains key
keys Return keys ofMapobject
remove Delete key-value pairs fromMapobject
values Return values ofMapobject

Topics

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 thecontainers.Mapclass.

Create Map Object

Create a Map using thecontainers.Mapclass.

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.