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help - Help for functions in Command Window

GUI Alternatives

Use the Function Browser by clicking its button, , or run doc functionname to view more extensive help for a function in the Help browser.

Syntax

help help / help functionname help modelname.mdl help methodname help classname help packagename help classname.name help packagename.classname.name help toolboxname help syntax t = help('topic')

Description

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

help / lists all operators and special characters, along with their descriptions.

help functionname displays a brief description and the syntax for functionname in the Command Window. The information is known as the help comments because it comes from the comments at the top of the MATLAB function file. For more information or related help, use the links in the help output. If functionname is overloaded, that is, appears in multiple folders on the search path, help displays the help comments for the first functionname found on the search path, and displays a hyperlinked list of the overloaded functions and their folders. If functionname is also the name of a toolbox, help also displays a list of subfolders and hyperlinked list of functions in the toolbox, as defined in the Contents.m file for the toolbox.

help modelname.mdl displays the complete description for the MDL-file modelname as defined in Model Properties > Description. If the Simulink product is installed, you do not need to specify the .mdl extension.

help methodname displays help for the method methodname. You may need to qualify methodname with its class.

help classname displays help for the class classname. You may need to qualify classname with its package.

help packagename displays help for the package packagename.

help classname.name displays help for the method, property, or event name in classname. You may need to qualify classname with its package.

help packagename.classname.name displays help for the method, property, or event name in classname, which is part of packagename. If you do not know the packangename, create an instance of classname and then run class(obj).

help toolboxname displays the Contents.m file for the specified folder named toolboxname, where Contents.m contains a list and corresponding description of MATLAB program files in toolboxname. toolboxname can be a partial path. If toolboxname is also a function name, help also displays the help comments for the function.

help syntax displays help comments describing the syntax used in MATLAB functions.

t = help('topic') returns the help text for topic as a string, with each line separated by /n, where topic is any allowable argument for help.

Note Some help displayed in the Command Window uses all uppercase characters for the names to make them stand out from the rest of the text. When typing these names, use lowercase characters.

Some names use mixed case. The help comments accurately reflect that. Use mixed case when typing these names. For example, the javaObject function uses mixed case.

Remarks

Prevent Scrolling of Long Help Pages

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.

Examples

help close displays help for the close function. It lists

help database.close displays help for the close function in the Database Toolbox™ product.

help throwAsCaller displays help for the MException.throwAsCaller method.

help MException displays help for the MException class.

help MException.cause displays help for the cause property of the MException class.

help containers displays help for the containers package.

help containers.Map displays help for the Map class in the containers package. Note that help Map does not provide help for the Map class, so include the packagename in the syntax.

help containers.Map.KeyType displays help for the KeyType property. Note thathelp Map.KeyType do not provide help for KeyType , so include the packagename in the syntax.

help datafeed displays help for the Datafeed Toolbox™ product.

help database lists the functions in the Database Toolbox product and displays help for the database function, because there is both a function and a toolbox called database.

help general lists all functions in the folder matlabroot/toolbox/matlab/general. This illustrates how to specify a partial path name rather than a full path name.

help f14_dap displays the description of the Simulink f14_dap.mdl model file (the Simulink product must be installed).

t = help('close') gets help for the function close and stores it as a string in t.