You can build an accelerated model, select the simulation mode, and run the simulation from the command prompt or from MATLAB® script. With this flexibility, you can create Accelerator mode MEX-files in batch mode, allowing you to build the C code and executable before running the simulations. When you use the Accelerator mode interactively at a later time, it will not be necessary to generate or compile MEX-files at the start of the accelerated simulations.
With the accelbuild command, you can build
a JIT accelerated execution engine without actually simulating the
model. For example, to build an Accelerator mode simulation of myModel:
accelbuild myModel
You can control the simulation mode from the command line prompt
by using the set_param command:
set_param('modelname','SimulationMode','mode')
The simulation mode can be normal, accelerator, rapid,
or external.
For example, to simulate your model with the Accelerator mode, you would use:
set_param('myModel','SimulationMode','accelerator')
sim command: simOut = sim('myModel', 'SimulationMode', 'accelerator');
You can use bdroot to set parameters for
the currently active model (that is, the active model window) rather
than modelname if you do not wish to explicitly
specify the model name.
For example, to simulate the currently opened system in the Rapid Accelerator mode, you would use:
simOut = sim(bdroot,'SimulationMode','rapid');
You can use set_param to configure the model
parameters (such as the simulation mode and the stop time), and use
the sim command to start
the simulation:
sim('modelname', 'ReturnWorkspaceOutputs', 'on');However, the preferred method is to configure model parameters
directly using the sim command, as shown in the
previous section.
You can substitute gcs for modelname if
you do not want to explicitly specify the model name.
Unless target code has already been generated, the sim command
first builds the executable and then runs the simulation. However,
if the target code has already been generated and no significant changes
have been made to the model (see Code Regeneration in Accelerated Models for a description),
the sim command executes the generated code without
regenerating the code. This process lets you run your model after
making simple changes without having to wait for the model to rebuild.
The following sequence shows how to programmatically simulate myModel in
Rapid Accelerator mode for 10,000 seconds.
First open myModel, and then type the following
in the Command Window:
simOut = sim('myModel', 'SimulationMode', 'rapid'...
'StopTime', '10000');
Use the sim command again to simulate after making a change to your model.
If the change is minor (adjusting the gain of a
gain block, for instance), the simulation runs
without regenerating code.
You can programmatically control the Accelerator mode and Rapid Accelerator mode build process and the amount of information displayed during the build process. See Customize the Build Process for details on why doing so might be advantageous.
Use SimCompilerOptimization to set the degree
of optimization used by the compiler when generating code for acceleration.
The permitted values are on or off.
The default is off.
Enter the following at the command prompt to turn on compiler optimization:
set_param('myModel', 'SimCompilerOptimization', 'on')
When SimCompilerOptimization is set to on in
JIT accelerated mode, the simulation time for some models improves,
while the build time can become slower.
Use the AccelVerboseBuild parameter to display
progress information during code generation. The permitted values
are on or off. The default is off.
Enter the following at the command prompt to turn on verbose build:
set_param('myModel', 'AccelVerboseBuild', 'on')