MATLAB: Is there an example of using SET_PARAM command in a MATLAB file S-function to update a parameter of any block in the model

%sfunctionmfiles-fcnsimulinktune

I have a Rate Limiter block in my model and I would like to change the Initial Condition parameter externally while the simulation is running. I am aware that I can use SET_PARAM command in MATLAB file S-function to change the parameter value. I would like to an example demonstrating this usage.

Best Answer

You can change the value of a block paramter using SET_PARAM command in the Output function of a MATLAB file S-function. Take a look at the attached model and S-function which demonstrates changing the Initial Condition of the Rate Limiter block to the Amplitude value of the Sine Wave block.

Related Solutions

MATLAB: Set_param ‘Table’ datatype

Assuming mydata is a row vector, this should work:

assert(isrow(mydata), 'data is not row vector');
set_param(char(my_table), 'Table', ['[', num2str(mydata), ']']);

Note that depending on the values in mydata you may need to tweak the format string of num2str to get an accurate representation of the numbers as text.

MATLAB: Is it possible to force the S-Function block to initialize completely before the other blocks during the course of a simulation in Simulink 7.3(R2009a)

The ability to force the S-Function block to initialize completely before the atomic subsystem during the course of simulation is available in Simulink 7.3 (R2009a).

In order to do so, please enter the following commands in the 'StartFcn' callback under 'Model Properties'.

set_param('Sfun_and_subsystem', 'SimulationCommand', 'pause')
set_param('Sfun_and_subsystem', 'SimulationCommand', 'update')
set_param('Sfun_and_subsystem', 'SimulationCommand', 'continue')

These commands will force the Simulink model to re-evaluate all blocks in the model for tunable parameter changes.

The extra update re-runs the S-Function initialization and forces the Constant block in the atomic subsystem to reinitialize.

Hence they pick up the model parameter values set in the S-Function initialization.

Best Answer

Related Solutions

MATLAB: Set_param ‘Table’ datatype

MATLAB: Is it possible to force the S-Function block to initialize completely before the other blocks during the course of a simulation in Simulink 7.3(R2009a)

Related Question