I am running Simulink from a Matlab function, as I need to start and stop the simulation multiple times changing parameters. When I run Simulink from the main script, there are no problems, Simulink can read the workspace. However, as soon as I make the script as a function so that I can run it for different input data.
function [Out] = Funtion (Var1, Var2 ....)
simout = sim('Simulinkblock');
Yx = simout.yout{1}.Values.Data;
Cx = Yx(end);
end
Simulink reads from the base workspace by default, you either need to change this using the following simset options in your function:
options = simset('SrcWorkspace','current');
sim('modelname',[],options)
Or assign the variables to the base workspace from your function using assignin before calling sim
Related
I was given the following protected Simulink model:
It works manually (I click on "Run" on the Simulink GUI and it gives me the three outputs).
I am writing a script using the Matlab SIMSET tool to define the necessary variables and to call this model in order to run it:
Constant=43;
Constant1=43;
Constant2=43;
Constant7=43;
Constant10=43;
Constant11=43;
t_stop = 100;
T_s = t_stop/1000;
options = simset('solver', 'ode5', 'fixedstep', T_s);
sim('test_lau.slx',t_stop,options)
I know that the interfaces "EC" and "UL" each take for input a vector, but even if I define two vectors in my script, how do I assign them to "EC" and "UL"?
Thank you in advance for your help!
I am building a Simulink model with Matlab Function blocks. These function blocks have a lot of constants, for example g=9.8. I want to initialize all of these constants in one go in a Matlab script, so that I don't have to do so in each function block.
Here's what I have tried until now:
In the Matlab Function block I have initialized the variables using a Constant block, which is given as a input to the function block. This system works, but there are a lot of constant blocks in the model and it's getting very clustered.
I have also tried declaring these variables as global variables in the Matlab script. This does not work.
Another way that I have tried is so to create a function script for these constants and then load this function script in the Matlab Function block. This does not work.
Is there a way that I can just initialize these values from the Matlab script and the Simulink model reads it from the Matlab script, without me having to use these constant blocks?
%refercode
%matlabscript
Initialization values;
sim('filenmae.slx');
post processing;
%simulink model
constant blocks(initialization values) -> matlab function block -> output;
%end
What's the best way to solve this problem?
You could have a single struct containing your variables, which can be selectively used in your Matlab Function blocks. This means you can just have a single Constant block and additional function input, intialized from your script.
This MathWorks article shows how you can convert the struct into a Simulink Bus for use in your model (you can't use the struct in a constant block directly):
https://blogs.mathworks.com/simulink/2011/12/05/initializing-buses-using-a-matlab-structure/
Giving you something like this:
% initialise constants within struct, keeps the workspace tidy too!
vars = struct();
vars.g = 9.8;
vars.lambda = 2;
% Create bus data for the variables struct
varsInfo = Simulink.Bus.createObject(vars);
% Sim the model
sim( 'myModel.slx' );
With your constant block configured for the bus as described in the linked article:
Then you can access this within your function
function y = ( y, vars )
% MATLAB Function block function within myModel.slx
y = vars.lambda + u * vars.g;
I got a script from this link and it runs correctly in MATLAB. However, when I create a Simulink model, it runs normally, but I can get the data from m file.
MATLAB script:
function data = Loadcell()
eml.extrinsic('arduino','addon','read_HX711')
a = arduino('COM5','Mega2560','libraries','ExampleAddon/HX711');
while 1
LoadCell = addon(a, 'ExampleAddon/HX711',{'D2','D3'});
data = read_HX711(LoadCell)
end
end
Simulink function
function data = Loadcell()
coder.extrinsic('Loadcell');
Loadcell = zeros('double');
data = zeros('double');
data = Loadcell
end
I run Simulink in external mode using Arduino and I don't get the data from that code. How can I use that MATLAB script to use it in the Simulink block model and get the data?
It's most likely a couple of issues
naming your Embedded MATLAB function in Simulink the same as the MATLAB function. (How would you expect Simulink to know which function it's supposed to call? The MATLAB function, or re-entering the Embedded MATLAB function?)
defining Loadcell as an extrinsic function, then (re)defining it to be a double 0.0, then trying to execute it as a function.
I suspect you want something like,
function data = Loadcell_Wrapper()
coder.extrinsic('Loadcell');
data = zeros(1,1,'double');
data = Loadcell()
end
(Also, not part of your question, but isn't there an infinite loop in the MATLAB code?)
I am running a simulink simulation through a matlab function , the function assign's the slx files values for its blocks and based on the output of the simulation it calculates something and sends an output, now the problem is that the variable values assigned to the blocks are local to the function and do not appear on the workspace but the slx files needs variables in the workspace like for example
function [return_result] = Test_Function(variablevalues1,variablevalues2)
for i =1:length(variablevalues1)
variable1 = variablevalues1(i);
variable2 = variablevalues2(i);
%do some calculation based on the result
return_result(end+1) = calculations
end
endfunction
so now i want to assign variable1 variable2 value to be assigned to the simulink blocks at each iteration, is there anyway ?
The "assignin" function is particularly useful for exporting data from a function to the MATLAB workspace.
I'm trying to simulate a very simple model using an embedded matlab function that takes the input and add's 10 to the value using a constant block that inputs into the matlab function, which then outputs to a display block.
As soon as I press simulate I get an abundance of errors. First I get a huge paragraph in orange text stating a warning out the solver 'variableStepDiscrete' instead of solver 'ode45'
Here is the remaining lines that are echo'd from the command prompt:
Code Directory :
"/Users/dazgti/Documents/MATLAB/slprj/_sfprj/embeddedFunction/_self/sfun/src"
Machine (#32): "embeddedFunction" Target : "sfun"
Chart "MATLAB Function" (#49):
.
"c2_embeddedFunction.h"
"c2_embeddedFunction.c"
"embeddedFunction_sfun.h"
"embeddedFunction_sfun.c"
"embeddedFunction_sfun_debug_macros.h"
Interface and Support files:
"embeddedFunction_sfun_registry.c"
Code generation failed Attempt to execute SCRIPT union as a function:
/Users/dazgti/Documents/MATLAB/union.m
I have a script file within my matlab directory called union.m, but I have no idea why its mentioning it.
function y = fcn(u)
%#codegen
x = u + 10;
y = x;
MATLAB Function block works by generating "C" code for the MATLAB code you entered in the block. In the process of generating code there could have been a call to union function in MATLAB from MATLAB Function block infrastructure. Since you have overridden the union function instead of the built-in function MATLAB might have attempted to call your script which caused the error. It is better to avoid naming your functions same as MATLAB built-in functions.