Propagate sizes of variable-size signals

Option to specify how variable-size signals propagate through referenced models

Model Configuration Pane: Model Referencing

Description

The Propagate sizes of variable-size signals configuration parameter determines how variable-size signals propagate through referenced models.

Set Configuration Parameter for Referenced Model

In a model reference hierarchy, how you open the Configuration Parameters dialog box determines whether you edit the configuration parameter for the top model in the current model hierarchy or the current referenced model.

• Top model in the current model hierarchy — In the Simulink^® Toolstrip, on the Modeling tab, click Model Settings.

• Current referenced model — In the Simulink Toolstrip, on the Modeling tab, click the Model Settings button arrow. Then, in the Referenced Model section, select Model Settings.

Alternatively, open the referenced model as a top model. Then, in the Simulink Toolstrip, on the Modeling tab, click Model Settings.

Dependencies

To enable this parameter, set Total number of instances allowed per top model to One or Multiple.

Settings

Infer from blocks in model (default) | Only when enabling | During execution

Infer from blocks in model

Searches a referenced model and groups blocks into the following categories.

Category	Description	Example Blocks in This Category
1	Output signal size depends on input signal values.	Switch block Enabled Subsystem block with an Enable block that sets Propagate sizes of variable-size signals to During execution
2	States require resetting when the input signal size changes.	Unit Delay block Enabled Subsystem block with an Enable block that sets Propagate sizes of variable-size signals to Only when enabling
3	Output signal size depends on only the input signal size.	Gain block

The search stops at the boundary of enable, function-call, and action subsystems because these subsystems can specify when to propagate the size of a variable-size signal.

This table describes how the software sets the propagation of variable-size signals for a referenced model.

Referenced Model Contents	Referenced Model Propagation of Variable-Size Signals
One or more blocks in category 1, and all other blocks in category 3	Supports During execution.
One or more blocks in category 2, and all other blocks in category 3	Supports Only when enabling.
Blocks in category 1 and category 2	Results in error.
All blocks in category 3 with at least one conditionally executed subsystem that is not an enable, function-call, or action subsystem	Results in error. In this case, the software cannot determine when to propagate sizes of variable-size signals.
All blocks in category 3 with only conditionally executed subsystems that are enable, function-call, or action subsystems	Supports both Only with enabling and During execution.

Only when enabling

Propagates sizes of variable-size signals for the referenced model only when enabling (at Enable method).

During execution

Propagates sizes of variable-size signals for the referenced model during execution (at Outputs method).

Recommended Settings

Application	Setting
Debugging	No impact
Traceability	No impact
Efficiency	No impact
Safety precaution	No recommendation

Programmatic Use

Parameter: PropagateVarSize

Value: 'Infer from blocks in model' | 'Only when enabling' | 'During execution'

Default: 'Infer from blocks in model'

Version History

Introduced in R2010a