Underspecified initialization detection

Description

Select how Simulink^® software handles initialization of initial conditions for conditionally executed subsystems, Merge blocks, subsystem elapsed time, and Discrete-Time Integrator blocks.

Category: Diagnostics

Settings

Default: Simplified

Classic

Initial conditions are initialized the same way they were prior to R2008b.

Simplified

Initial conditions are initialized using the enhanced behavior, which can improve the consistency of simulation results.

Tips

• Use Classic to ensure compatibility with previous releases of Simulink. Use Simplified to improve the consistency of simulation results, especially for models that do not specify initial conditions for conditional subsystem output ports, and for models that have conditionally executed subsystem output ports connected to S-functions. For more information, see Simplified Initialization Modeand Classic Initialization Mode.

• For existing models, MathWorks^® recommends using the Model Advisor to migrate your model to the new settings. To migrate your model to simplified initialization mode, run the following Model Advisor checks:

  • Check usage of Merge blocks

  • Check usage of Outport blocks

  • Check usage of Discrete-Time Integrator blocks

  • Check model settings for migration to simplified initialization mode

  For more information, see Convert from Classic to Simplified Initialization Mode.

• When using Simplified initialization mode, you must set Bus signal treated as vector to error on the Connectivity Diagnostics pane.

Dependencies

Selecting Classic enables the following parameters:

• Detect multiple driving blocks executing at the same time step

• Check undefined subsystem initial output

• Check runtime output of execution context

Selecting Simplified disables these parameters, and automatically sets Detect multiple driving blocks executing at the same time step to error.

Command-Line Information

Parameter: UnderspecifiedInitializationDetection

Value: 'Classic' | 'Simplified'

Default: 'Classic'

Recommended Settings

Application	Setting
Debugging	Simplified
Traceability	Simplified
Efficiency	Simplified
Safety precaution	Simplified