help

Help for functions in Command Window

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Syntax

help
help name

Description

help lists all primary help topics in the Command Window. Each main help topic corresponds to a folder name on the MATLAB® search path.

help name displays the help text for the functionality specified by name, such as a function, method, class, toolbox or variable.

Input Arguments

name

Operator symbol (such as +) or name of a function, class, method, package, toolbox folder, variable, or other functionality, specified as a character vector.

Some classes and other packaged items require that you specify the package name. Events, properties, and some methods require that you specify the class name. Separate the components of the name with periods, such as:

help className.name
help packageName.name
help packageName.className.name

If name is a variable, help displays the help text for the class of that variable.

help name

To get help for the methods of the name class, specify

help name.methodname

If name is overloaded, that is, appears in multiple folders on the search path, help displays the help text for the first instance of name found on the search path, and displays a hyperlinked list of the overloaded functions and their folders.

When name specifies the name or partial path of a toolbox folder:

  • If the folder contains a nonempty Contents.m file, the help function displays the file. Contents.m contains a list of MATLAB program files in the folder and their descriptions. If Contents.m exists, but is empty, MATLAB responds with No help found for name.

  • If the folder does not contain a Contents.m file, the help function lists the first line of help text for each program file in the folder.

  • If name is the name of both a function and a toolbox, help displays the associated text for both the toolbox and the function.

Examples

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Display help for the MATLAB close function.

help close

Because close refers to the name of a function and to the name of several methods, the help text includes hyperlinks to the overloaded methods.

Request help for the Database Toolbox™ close method.

help database.close

Display help for the containers package, Map class, and the isKey method.

help containers
help containers.Map
help containers.Map.isKey

Not all packages, classes, and associated methods or events require complete specification. For example, display the help for the throwAsCaller method of the MException class.

help throwAsCaller

Display help for a variable t = datetime.

t = datetime
help t

Because t is of type datetime, the help function displays help text for the datetime class.

Request help for Day, a method of the datetime class.

help t.Day

List all of the functions in the folder matlabroot/toolbox/matlab/general by specifying a partial path.

help general

Tips

  • Some help text displays the names of functions in uppercase characters to make them stand out from the rest of the text. When typing these function names, use lowercase. For function names that appear in mixed case (such as javaObject), type the names as shown.

  • To prevent long descriptions from scrolling off the screen before you have time to read them, enter more on, and then enter the help statement.

  • Some classes require that you specify the package name to display the help text. To identify the package name, create an instance of the class, and then call class(obj).

Alternatives

View more extensive help using the doc command or the Function Browser. To open the Function Browser, click its icon, .

See Also

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Topics

Introduced before R2006a

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