Using Simulink

The Model Browser

The Model Browser enables you to:

• Navigate a model hierarchically
• Open systems in a model directly
• Determine the blocks contained in a model
• Use your source control system to manage the model. Refer to "Interfacing with Source Control Systems" in the MATLAB documentation.

The browser operates differently on Microsoft Windows and UNIX platforms.

Using the Model Browser on Windows

To display the Model Browser, select Model Browser from the Simulink View menu. The model window splits into two panes. The left pane displays the browser, a tree-structured view of the block diagram displayed in the right pane.

Note    The Browser initially visible preference causes Simulink to open models by default in the Model Browser. To set this preference, select Preferences from the Simulink File menu.

The top entry in the tree view corresponds to your model. A button next to the model name allows you to expand or contract the tree view. The expanded view shows the model's subsystems. A button next to a subsystem indicates that the subsystem itself contains subsystems. You can use the button to list the subsystem's children. To view the block diagram of the model or any subsystem displayed in the tree view, select the subsystem. You can use either the mouse or the keyboard to navigate quickly to any subsystem in the tree view.

Navigating with the Mouse.   Click any subsystem visible in the tree view to select it. Click the + button next to any subsystem to list the subsystems that it contains. Click the button again to contract the entry.

Navigating with the Keyboard.   Use the up/down arrows to move the current selection up or down the tree view. Use the left/right arrow or +/- keys on your numeric keypad to expand an entry that contains subsystems.

Showing Library Links.   The Model Browser can include or omit library links from the tree view of a model. Use the Simulink Preferences dialog box to specify whether to display library links by default. To toggle display of library links, select Show library links from the Model browser options submenu of the Simulink View menu.

Showing Masked Subsystems.   The Model Browser can include or omit masked subsystems from the tree view. If the tree view includes masked subsystems, selecting a masked subsystem in the tree view displays its block diagram in the diagram view. Use the Simulink Preferences dialog box to specify whether to display masked subsystems by default. To toggle display of masked subsystems, select Look under masks from the Model browser options submenu of the Simulink View menu.

Using the Model Browser on UNIX

To open the Model Browser, select Show Browser from the File menu. The Model Browser window appears, displaying information about the current model. This figure shows the Model Browser window displaying the contents of the clutch system.

Contents of the Browser Window

The Model Browser window consists of:

• The systems list. The list on the left contains the current system and the subsystems it contains, with the current system selected.
• The blocks list. The list on the right contains the names of blocks in the selected system. Initially, this window displays blocks in the top-level system.
• The File menu, which contains the Print, Close Model, and Close Browser menu items.
• The Options menu, which contains the menu items Open System, Look Into System, Display Alphabetical/Hierarchical List, Expand All, Look Under Mask Dialog, and Expand Library Links.
• The Options check boxes and buttons Look Under [M]ask Dialog and Expand [L]ibrary Links check boxes, and Open System and Look Into System buttons. By default, Simulink does not display contents of masked blocks and blocks that are library links. These check boxes enable you to override the default.
• The block type of the selected block.
• Dialog box buttons Help, Print, and Close.

Interpreting List Contents

Simulink identifies masked blocks, reference blocks, blocks with defined OpenFcn parameters, and systems that contain subsystems using these symbols before a block or system name:

• A plus sign (+) before a system name in the systems list indicates that the system is expandable, which means that it has systems beneath it. Double-click on the system name to expand the list and display its contents in the blocks list. When a system is expanded, a minus sign (-) appears before its name.
• [M] indicates that the block is masked, having either a mask dialog box or a mask workspace. For more information about masking, see Chapter 7, Using Masks to Customize Blocks.
• [L] indicates that the block is a reference block. For more information, see Connecting Blocks.
• [O] indicates that an open function (OpenFcn) callback is defined for the block. For more information about block callbacks, see Using Callback Routines.
• [S] indicates that the system is a Stateflow block.

Opening a System

You can open any block or system whose name appears in the blocks list. To open a system:

1. In the systems list, select by single-clicking on the name of the parent system that contains the system you want to open. The parent system's contents appear in the blocks list.
2. Depending on whether the system is masked, linked to a library block, or has an open function callback, you open it as follows:
   • If the system has no symbol to its left, double-click on its name or select its name and click on the Open System button.
   • If the system has an [M] or [O] before its name, select the system name and click on the Look Into System button.

Looking into a Masked System or a Linked Block

By default, the Model Browser considers masked systems (identified by [M]) and linked blocks (identified by [L]) as blocks and not subsystems. If you click on Open System while a masked system or linked block is selected, the Model Browser displays the system or block's dialog box (Open System works the same way as double-clicking on the block in a block diagram). Similarly, if the block's OpenFcn callback parameter is defined, clicking on Open System while that block is selected executes the callback function.

You can direct the Model Browser to look beyond the dialog box or callback function by selecting the block in the blocks list, then clicking on Look Into System. The Model Browser displays the underlying system or block.

Displaying List Contents Alphabetically

By default, the systems list indicates the hierarchy of the model. Systems that contain systems are preceded with a plus sign (+). When those systems are expanded, the Model Browser displays a minus sign (-) before their names. To display systems alphabetically, select the Display Alphabetical List menu item on the Options menu.

Searching for Objects

Managing Model Versions