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help

Help for functions in Command Window

Description

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

example

help displays content relevant to your previous actions.

Examples

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Display help for the MATLAB® delete function.

help delete
delete - Delete files or objects
    This MATLAB function deletes filename from disk, without requesting
    verification.

    Syntax
      delete filename
      delete filename1 ... filenameN
      delete ___ ResolveSymbolicLinks=tf
      delete(obj)delete Delete file or graphics object.
...

Because delete is the name of a function and of several methods, the help text includes a link to a list of the methods with the same name. Request help for the delete method of the handle class.

help handle/delete
handle/delete - Delete handle object
    This MATLAB function deletes the handle object.

    Syntax
      delete(H)
...

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

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

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

help throwAsCaller

Display help for a variable of type datetime. Because t is of type datetime, the help command displays help text for the datetime class.

t = datetime;
help t
--- help for datetime ---

 datetime - Arrays that represent points in time
    The datetime data type represents points in time, such as August 24,
    2020, 10:50:30 a.m.

    Creation
...

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

help t.Day
--- help for datetime/Day ---

 datetime/Day - Day-of-month number
  numeric array
...

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

help timefun
Timing functions.
    cputime          - CPU time in seconds.
    tic              - Start stopwatch timer.
    toc              - Stop stopwatch timer.
    etime            - Elapsed time.
    pause            - Wait in seconds.
...

Input Arguments

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Functionality name, such as the name of a function, method, class, toolbox, or variable, specified as a character vector or string scalar. name also can be an operator symbol (such as +).

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

To get help for a method of a class, specify the class name and the method name, separated with a period. For example, to get help for the methodname method of the classname class, type help classname.methodname.

Some classes and other namespace items require that you specify the namespace name. Events, properties, and some methods require that you specify the class name. Separate the components of the name with periods. For example, to get help for the propertyname property of the classname class, type classname.propertyname. To get help for the classname class in the namespacename namespace, type namespacename.methodname. To get help for the methodname method of the classname class in the namespacename namespace, type namespacename.classname.methodname.

If name appears in multiple folders on the MATLAB search path, help displays the help text for the first instance of name found on the search path.

If name is overloaded, help displays a link to a list of the methods with the same name.

If name specifies the name or partial path of a 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 the folder contains an empty Contents.m file, the help function displays name is a folder.

  • 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 folder and another item on the MATLAB search path (such as a method, class, toolbox, or variable), the help function displays the associated text for the item on the search path and a link to display the help text for the folder.

Tips

  • 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.

  • To identify the namespace name for a class, create an instance of the class, and then call class(obj).

Alternative Functionality

View more extensive help using the doc command or the Function Browser.

Version History

Introduced before R2006a