Documentation

Editor

Select which editor you want the MATLAB desktop to use when you edit a file:

If you select Text editor, specify the full path for the editor application you want to use, such as Emacs or vi. For example, c:/Applications/Emacs.exe.

This preference only applies to plain text files such as files with a .m or .txt extension.

Most recently used file list

In the Number of entries field, type the number of files that you want to appear in the list of recently used files at the bottom of the File menu.

Opening files in editor

Select On restart reopen files from previous MATLAB sessions if you want the Editor and the files it contained during your last MATLAB session to reopen when you restart MATLAB.

Select Automatically open files when MATLAB reaches a breakpoint to open a running program file when MATLAB encounters a breakpoint in that file.

Automatic file changes

Select Save changes upon clicking away from a file if you want the Editor to automatically save changes to a file in the Editor when you click away from the Editor. For the changes to be automatically saved upon clicking away from the Editor, you must have already saved the file at least once.

Select Reload unedited files that have been externally modified if you want the Editor to automatically reload the version of a file that you opened and edited outside of MATLAB when the file currently open in the Editor has no unsaved changes.

Select Add line termination at end of file to have MATLAB add a new empty line (sometimes referred to as a <CR>) to the end of a file automatically if the last line in the file is not empty.

This preference only applies to plain text files such as files with a .m or .txt extension.

Debugging in the Live Editor

Select Only show Step in button for user-defined functions to have the Live Editor only step into user-defined functions and scripts. To have the Live Editor step into MathWorks^® functions as well, clear the option.

Select Highlight Current Line and select a color to highlight the row with the cursor (also called the caret).

This preference does not apply in the Live Editor.

Select Show line numbers to display line numbers along the left edge of the Editor and Live Editor window.

Select Enable data tips in edit mode to display data tips when you are editing a MATLAB code file. (Data tips are always enabled in debug mode.)

For details, see View Variable Value.

This preference does not apply in the Live Editor.

Select Display the Open as a Live Script banner if you want the Open as a Live Script banner to appear at the top of documents in the Editor.

Select Show line to display a vertical line with the specified Width and Color at the specified column (Placement) in the Editor.

For details, see Right-Side Text Limit Indicator.

This preference does not apply in the Live Editor.

Specify the amount of space inserted when you press the Tab key.

When you change the Tab size, it changes the tab size for existing lines in that file, unless you also select Tab key inserts spaces.

Specify the indent size for smart indenting. Smart indenting is one of the Editor/Debugger Language Preferences.

Select to insert a series of spaces when you press the Tab key. Otherwise, a tab acts as one space whose length is equal to the Tab size.

Specifies an indenting style similar to the style that the Emacs editor uses.

Lines indent according to smart indenting preferences when you position the cursor in a line or select a group of lines, and then press the Tab key.

Smart indenting is one of the Editor/Debugger Language Preferences.

If you select this preference, you cannot insert tabs within a line.

Select the language for which you want to set preferences.

Syntax highlighting

Select Enable syntax highlighting to have the Editor and Live Editor use different colors for different language constructs. Then, adjust the colors you want to use for each language element.

Access color options for the MATLAB language by clicking Set syntax colors.

For all other languages, color options appear under Enable syntax highlighting.

For details, see Syntax Highlighting.

Variable and function renaming

MATLAB Language only

Select Enable automatic variable and function renaming to have MATLAB prompt you to rename all instances of a function or variable in a file when you rename a function or variable.

For details on when MATLAB prompts you, see Automatically Rename All Functions or Variables in a File.

Comment formatting

MATLAB Language only

In the Maximum column width field, enter the maximum number of characters you want to allow in a line of comments, and then select where you want counting to begin.

Consider selecting:

Select Wrap comments automatically while typing to automatically wrap comments at the Maximum column width value when you type comments in an Editor or Live Editor document.

If you clear this option, you can still wrap comments manually, as described in Add Comments to Programs.

Indenting

Select Apply smart indenting while typing to automatically:

This is called smart indenting. You also can manually apply smart indenting after you type the code.

For more information, see Indenting Code.

Select an option from Function Indenting Format (MATLAB Language only) to specify how functions indent in the Editor and Live Editor, as follows:

For more information and examples of each indenting format, see Indenting Code.

Add one or more file extensions to associate with the Language. The preferences you set for that language apply to all files with the listed extensions.

Specifies whether you want code folding enabled for the programming constructs that have their corresponding Enable check box selected.

Specifies whether you want code folding enabled for the corresponding Programming Construct.

If you select this option for any construct, but clear the Enable Code Folding option, the construct will not have code folding enabled.

Automatically create backup files while working in the MATLAB Editor

Save untitled files saves a copy of new, untitled, files to Untitled.asv.

When there is more than one untitled file, each additional file is saved to Untitledn.asv (where n is an integer value).

For details, see Backing Up Files.

Automatically delete backup files when the Editor closes directs MATLAB to delete the backup file when you close the source file in the Editor.

Select the naming convention you want MATLAB to use for autosave files. For example:

Source file directories specifies that you want backup files stored in the same folder as the files being edited.

Single directory specifies that you want autosave files stored in a single folder. Specify the full path to that folder and be sure you have write permissions for it.

Enable autoformatting in Live Editor

Text format

Section break

Insert Options

Text Style

Enable autocoding in Live Editor and App Designer

Autocomplete parentheses

Autocomplete quotes

Autocomplete when splitting

Select Comments (%) to enable autocompletion of comments when split across two lines. For example, pressing Enter with your cursor after the period in the comment

% This is my first comment. This is my second comment.

% This is my first comment.
% This is my second comment.

Select Character vectors (' ') to enable autocompletion of character vectors when split across two lines. For example, pressing Enter with your cursor after the word Random in the character vector

title('Mean of Random Uniform Data')

title(['Mean of Random' ...
    ' Uniform Data'])

Select Strings (" ") to enable autocompletion of strings when split across two lines. For example, pressing Enter with your cursor after the word long in the string

exist("exceptionally_long_file_name.txt")

exist("exceptionally_long" + ...
    "_file_name.txt")

Select Parentheses () to enable autocompletion of parentheses when split across two lines. For example, pressing Enter with your cursor after the number 10 and the comma in the command

plot(x,y,'--gs','LineWidth',2,'MarkerSize',10,'MarkerEdgeColor','b')

plot(x,y,'--gs','LineWidth',2,'MarkerSize',10, ...
    'MarkerEdgeColor','b')

Autocomplete block endings

Select Control flow statements (if, for, etc.) to enable autocompletion of control flow statements. To autocomplete a statement, enter the statement and press Enter. For a list of control flow statements, see Loops and Conditional Statements.

Select Function and class definitions to enable autocompletion of functions and class definitions. To autocomplete a definition, enter either function or class and press Enter.