sim

You can use a Simulink.SimulationInput object to store the configuration for a simulation separate from the model you simulate. The configuration in the Simulink.SimulationInput object is applied to the model for the simulation. After simulation, any model settings that were changed revert to the original value.

Open the model IntegrateSine. The model uses an Integrator block to integrate the output of a Sine Wave block. The output from the Integrator block is connected to an Outport block.

mdl = "IntegrateSine";
open_system(mdl)

Create a Simulink.SimulationInput object to store a simulation configuration for the model IntegrateSine.

simIn = Simulink.SimulationInput(mdl);

Use the setModelParameter function to configure the SimulationInput object to use the ode45 solver and to simulate to a stop time of 20 seconds.

simIn = setModelParameter(simIn,"Solver","ode45",...
    "StopTime","20");

Use the setBlockParameter function to configure the SimulationInput object to set the Amplitude parameter of the Sine Wave block to 2.

blk = strcat(mdl,"/Sine Wave");
simIn = setBlockParameter(simIn,blk,"Amplitude","2");

Simulate the model using the configuration stored in the Simulink.SimulationInput object simIn.

out = sim(simIn);

The model simulates for 20 seconds, using the ode45 solver and an amplitude of 2 for the Sine Wave block.

When you use an array of Simulink.SimulationInput objects to configure a set of simulations, you can use a single call to the sim function to run the set of simulations using fast restart. Fast restart saves time in simulation by keeping the model compiled between simulation runs.

Open the model IntegrateSine. The model uses an Integrator block to integrate the output of a Sine Wave block. The output from the Integrator block is connected to an Outport block.

mdl = "IntegrateSine";
open_system(mdl)

Suppose you want to run a set of six simulations that each use a different frequency value for the Sine Wave block. Create a vector that contains the frequency values for the simulations.

freqs = [0.5 1 1.5 2 2.5 3];

When you want to tune a block parameter, you can define the value of the parameter using a variable. Then, to tune the block parameter, you change the value of the variable.

Define the variable freq to use for the value of the Frequency parameter for the Sine Wave block. For the initial variable value, use the current parameter value.

blk = mdl + "/Sine Wave";
freq = str2double(get_param(blk,"Frequency"));

Set the Frequency parameter value for the Sine Wave block to freq.

set_param(blk,"Frequency","freq")

In a for loop, create an array of six Simulink.SimulationInput objects and use the setVariable function to configure each object to use a value from the vector of frequencies.

for k = length(freqs):-1:1
    simIn(k) = Simulink.SimulationInput(mdl);
    simIn(k) = setVariable(simIn(k),"freq",freqs(k));
end

Run the simulations defined by the array of SimulationInput objects simIn using the sim function. Enable fast restart using the UseFastRestart name-value argument. The UseFastRestart name-value argument is supported only when the first input argument is a Simulink.SimulationInput object. To use fast restart when the first argument is the name of a model, use the FastRestart name-value argument.

out = sim(simIn,"UseFastRestart","on");

[28-Feb-2023 11:45:06] Running simulations...
[28-Feb-2023 11:45:11] Completed 1 of 6 simulation runs
[28-Feb-2023 11:45:12] Completed 2 of 6 simulation runs
[28-Feb-2023 11:45:12] Completed 3 of 6 simulation runs
[28-Feb-2023 11:45:12] Completed 4 of 6 simulation runs
[28-Feb-2023 11:45:12] Completed 5 of 6 simulation runs
[28-Feb-2023 11:45:12] Completed 6 of 6 simulation runs

To run the same set of simulations without showing the progress messages, specify the ShowProgress name-value argument as off.

out = sim(simIn,"UseFastRestart","on","ShowProgress","off");

To monitor the progress of the simulations using the Simulation Manager, specify the ShowSimulationManager name-value argument as on. For more information about the Simulation Manager, see Simulation Manager.

out = sim(simIn,"UseFastRestart","on",...
    "ShowProgress","off","ShowSimulationManager","on");

The simulation output out is an array of Simulink.SimulationOutput objects that contain the metadata and results for each simulation. The order of SimulationOutput objects in the output array matches the order of SimulationInput objects in the input array. For example, the SimulationOutput object at index 1 contains the results of the simulation configured using the SimulationInput object at index 1.

Access the logged output signal for the results of the first simulation, which used a frequency value of 0.5.

youtPt5 = out(1).yout

youtPt5 = 
Simulink.SimulationData.Dataset 'yout' with 1 element

                         Name    BlockPath             
                         ______  _____________________ 
    1  [1x1 Signal]      output  IntegrateSine/Outport

  - Use braces { } to access, modify, or add elements using index.

Open the model IntegrateSine. The model uses an Integrator block to integrate the output of a Sine Wave block. The output from the Integrator block is connected to an Outport block.

mdl = "IntegrateSine";
open_system(mdl);

Simulate the model using the current configuration parameter values.

out = sim(mdl);

The simulation runs for 10 seconds, integrating a sine wave with an amplitude of 1.

You can modify model configuration parameter values and block parameter values in the model using the set_param function.

Configure the model to use the ode45 solver and a stop time of 20 seconds.

set_param(mdl,"Solver","ode45","StopTime","20")

Set the Amplitude parameter of the Sine Wave block to 2.

blk = strcat(mdl,"/Sine Wave");
set_param(blk,"Amplitude","2")

When you modify a configuration parameter value or block parameter value using the set_param function, the change applies to the block diagram and dirties the model file. When you call the sim function again, the simulation uses the new parameter values, which are part of the current model configuration, even if you do not save the model.

out2 = sim(mdl);

The simulation runs for 20 seconds, integrating a sine wave with an amplitude of 2.

You can configure a simulation of a model to use different values for model configuration parameter values by specifying the configuration parameters for the simulation as name-value arguments for the sim function. The parameter values you specified are applied for the simulation and reverted when the simulation completes.

You can specify only model configuration parameter values and not block parameter values as name-value arguments for the sim function. To specify model configuration parameter values, block parameter values, and variable values for a simulation in a single input, use a Simulink.SimulationInput object instead.

Open the model IntegrateSine. The model uses an Integrator block to integrate the output of a Sine Wave block. The output from the Integrator block is connected to an Outport block.

mdl = "IntegrateSine";
open_system(mdl);

Suppose you want to simulate the model using the solver ode45 and a stop time of 20 seconds. Specify the Solver and StopTime values for the simulation as name-value arguments for the sim function.

out = sim(mdl,"Solver","ode45","StopTime","20");

The model simulates through a simulation time of 20 seconds using the solver ode45.

You can use a structure of model configuration parameter names and values to configure a simulation of a model. The configuration parameter values in the structure are applied to the model for the simulation. After simulation, any model settings that changed are reverted to the original value.

The structure input can specify only model configuration parameter values and cannot specify different block parameter or variable values to use in the simulation. To specify model configuration parameter values, block parameter values, and variable values for a simulation in a single input, use a Simulink.SimulationInput object instead.

Open the model IntegrateSine. The model uses an Integrator block to integrate the output of a Sine Wave block. The output from the Integrator block is connected to an Outport block.

mdl = "IntegrateSine";
open_system(mdl)

Create the structure SimConfig that configures a simulation to use the ode45 solver and a stop time of 20 seconds. The structure contains a field for each configuration parameter to modify in the simulation. The name of each field matches the programmatic name for each parameter. The value of each field specifies the value to use for that parameter in the simulation.

simConfig.Solver = "ode45";
simConfig.StopTime = "20";

Simulate the model using the model configuration parameter values from the structure.

out = sim(mdl,simConfig);

The model simulates through a simulation time of 20 seconds using the ode45 solver.

A Simulink.ConfigSet object stores a set of model configuration parameter values. You can specify a Simulink.ConfigSet object as an input to the sim function. The configuration set from the object is applied to the model for the simulation. After simulation, the original configuration set is restored in the model.

A Simulink.Configset object stores only model configuration parameter values. To specify model configuration parameter values, block parameter values, and variable values for a simulation in a single input, use a Simulink.SimulationInput object instead.

Open the model IntegrateSine. The model uses an Integrator block to integrate the output of a Sine Wave block. The output from the Integrator block is connected to an Outport block.

mdl = "IntegrateSine";
open_system(mdl)

Use the getActiveConfigSet function to get a Simulink.ConfigSet object for the current model configuration.

mdlConfig = getActiveConfigSet(mdl);

Use the copy function to create a copy of the Simulink.ConfigSet object to modify.

simConfig = copy(mdlConfig);

Modify the Simulink.ConfigSet object simConfig to use the solver ode45 and a stop time of 20 seconds.

set_param(simConfig,"Solver","ode45","StopTime","20");

Simulate the model using the configuration parameters in the Simulink.Configset object simConfig.

out = sim(mdl,simConfig);

The model simulates through a simulation time of 20 seconds using the ode45 solver.