Propagate sizes of variable-size signals

Description

Select how variable-size signals propagate through referenced models.

Category: Model Referencing

Settings

Default: Infer from blocks in model

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.

Simulink^® sets the propagation of variable-size signals for a referenced model as follows:

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	Errors.
All blocks in category 3 with at least one conditionally executed subsystem that is not an enable, function-call, or action subsystem	Errors. In this case, Simulink 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).

Command-Line Information

Parameter: PropagateVarSize

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

Default: 'Infer from blocks in model'

Recommended Settings

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