Edit and Format Code

Column Selection

When editing code in the Editor you can select and edit a rectangular area of code (also known as column selection or block edit). If you want to copy or delete several columns of data (as opposed to rows) or if you want to edit multiple lines at one time, selecting and editing code is useful. To select a rectangular area, press the Alt key while making a selection with the mouse. On macOS systems, use the Option key instead.

For example, select the second column of data in A.

Type 0 to set all the selected values to 0.

Change Case

You can change the case of selected text or code between uppercase and lowercase in the Editor. Select the text, right-click, and select Change Case. Alternatively, you can press Ctrl+Shift+A. If the text contains uppercase and lowercase text, MATLAB^® changes the case to all uppercase.

On macOS, use the Command key instead of the Ctrl key.

Duplicate and Copy Line

You can duplicate a code line in the Editor. To duplicate a code line, right-click the line and select Duplicate Line(s). Alternatively, you can press Ctrl+Shift+C. On macOS, use the Command key instead of the Ctrl key.

To copy a code line without selecting the code, press the Ctrl+L keyboard shortcut. To cut the code line, press Ctrl+X. On macOS, use the Command+C and Command+X keyboard shortcuts instead. (since R2025a)

Automatically Complete Code

MATLAB automatically completes parentheses and quotes when entering code in the Editor. For example, if you type an open parenthesis in the Editor, MATLAB adds the closing parenthesis. MATLAB also automatically splits comments, character vectors, strings, and parentheses when you press Enter. For example, if you press Enter in a comment, MATLAB moves the text after the cursor to a new line and adds a percent (%) symbol to the beginning of the new line.

MATLAB can also automatically complete block endings in control flow statements and function and class definitions. To autocomplete block endings, on the Home tab, in the Environment section, click Settings. Select Editor/Debugger > Suggestions and Autocompletions and in the Autocoding options section, select one or more of the Autocomplete block endings options.

To undo an automatic code completion, press Ctrl+Z or the Undo button. To disable all automatic code completions, in the Autocoding options section of the Editor/Debugger > Suggestions and Autocompletions settings, clear the Enable autocoding setting. Alternatively, to disable only certain automatic code completions, clear one or more of the settings in the Autocomplete pairs, Autocomplete on new line, and Autocomplete block endings sections. For more information, see Editor/Debugger Settings.

Refactor Code

You can break large scripts or functions into smaller pieces by converting selected areas of code into functions or local functions, known as code refactoring.

To refactor a selected area of code:

Indent Code

Indenting code makes functions and statements, such as while loops, easier to read. By default, MATLAB automatically indents code in the Editor as you type. This is called smart indenting. When you indent lines by using tabs or spaces, MATLAB also aligns subsequent lines with those lines.

To indent selected lines of code if smart indenting is disabled, go to the Editor or Live Editor tab and in the Code section, click the Smart Indent button.

To manually change the indent of selected lines to be farther right or left, on the Editor or Live Editor tab, click the Increase Indent or Decrease Indent buttons. Manually changing the indent works whether smart indenting is enabled or disabled. Alternatively, you can use the Tab key or the Shift+Tab keys, respectively.

s = settings;
s.matlab.editor.indent.SmartIndentEntireDocument.PersonalValue = 1;

Change Line Endings

Since R2026a

By default, the end-of-line sequence for new files on Windows^® is the carriage return and line feed characters (\r\n). On Linux^® and macOS, the default end-of-line sequence for new files is the line feed character (\n).

To change the default end-of-line sequence, go to the Home tab, and in the Environment section, click Settings. Select MATLAB > Editor/Debugger, and then select an option for Default end of line sequence.

To change the end-of-line sequence for the file currently open in the Editor, click the end-of-line sequence indicator at the bottom-right corner of the MATLAB desktop and select the end-of-line sequence style to use. (since R2026b)

Changing the end-of-line sequence is not supported for code files saved in the binary live code file format (.mlx) or for apps saved in the binary file format (.mlapp).

Wrap Long Code Lines

Since R2026b

If your code file contains long code lines, the Editor can display those code lines across multiple visual lines without adding line breaks. This display-only wrapping helps you avoid horizontal scrolling while preserving the original code.

To enable wrapping long code lines, go to the View tab, and in the Display section, toggle the Wrap Code Lines button on. Alternatively, go to the Home tab, and in the Environment section, click Settings. Select Editor/Debugger > Display, and select the Wrap long code lines for display only setting.

Change the Right-Side Text Limit Indicator

By default, a light gray vertical line (rule) appears at column 75 in the Editor, indicating where a line exceeds 75 characters. You can set this text limit indicator to another value, which is useful, for example, if you want to view the code in another text editor that has a different line width limit. The right-side text limit indicator is not supported in live scripts and live functions.

To hide or change the appearance of the vertical line:

The right-side text limit indicator is a visual cue only and does not prevent text from exceeding the limit. To wrap comment text at a specified column number automatically, go to the Home tab and in the Environment section, click Settings. Select MATLAB > Editor/Debugger > MATLAB Language, and adjust the Comment formatting settings.

Before R2025a: Select MATLAB > Editor/Debugger > Language and in the Language field, select MATLAB.

Fold Code

Code folding expands and collapses blocks of MATLAB code in the Editor. You can use code folding to hide code that you are not currently working on. Code folding improves the readability of a file that contains numerous functions or other blocks of code. Code folding is not supported in live scripts and live functions.

For example, you can fold:

To expand or collapse a block of code, click the plus or minus sign that appears to the left of the construct in the Editor. Alternatively, you can use the Ctrl+Shift+. (period) and Ctrl+. (period) keyboard shortcuts or use the code folding buttons in the View tab.

To expand or collapse all of the code in a file, place your cursor anywhere within the file, go to the View tab, and select the Expand All or Collapse All buttons. Alternatively, you can use the Ctrl+Shift+, (comma) and Ctrl+, (comma) keyboard shortcuts.

You can change which programming constructs can be folded and whether a programming construct is collapsed the first time that you open a MATLAB file. On the Home tab, in the Environment section, click Settings. Select Editor/Debugger > Code Folding, and then adjust the setting options.

View Outline of Code

Since R2025a

You can view a high-level outline of MATLAB code files using the Outline panel. To view the outline of a file open in the Editor, go to the View tab, and in the Tools section, click Outline. Alternatively, click the Open more panels button on a sidebar and select the Outline panel.

In the Outline panel, you can: