is it possible to use cell array in matlab function block in simulink? - matlab

i have a Structure that describe my fuzzy system and I'm gonna to use it on MATLAB Simulink in general for fuzzy type 1 i could use fuzzy logic controller block BUT i have fuzzy type 2 and a structure describe it's membership functions and other attribute, i have to use it on simulink but matlab function block in simulink can't generate code for a cell array and i receive error.
so i ask you guys please help me:
is it possible to use cell array in matlab function block in simulink?

The MATLAB Function block supports all the data types that Simulink supports, see Data Types Supported by Simulink, and so I believe cell arrays aren't supported. However, you should be able to use the Fuzzy Logic Controller from the Fuzzy Logic Toolbox.

Related

Heterogeneous data from workspace into Simulink

I have different matrices to import into a Simulink Matlab function from the workspace. These matrices have all different dimension, which I don´t know at priori.
At the beginning I tried using the block 'constant' putting the data all together in a structure like this:
But then, I cannot pick the right matrix since I don´t know the dimension of each element (and also 'mux' cannot be used to split matrices).
I think I will have the same problem also with the block 'from workspace'.
I was wondering if there is a smart way to import heterogeneous structures like these. I tried also with cell-arrays, but it seems to be not supported by Simulink.
Thanks for any suggestions.
If the data is to be used in a Matlab Function block you could define the workspace matricies as parameters in the model explorer and in the Matlab Function port editor. You then have them accessible inside that function without even needing the "const" blocks or drawing any signals.
Even if your final intent is not to have data into a Matlab Function block those blocks are quite useful for extracting signals from heterogeneous data since you can do some size/type checking in them. Then you can output "simulink friendly" signals for use elsewhere.

Structure as input for a Matlab function Block

I have a, in my opinion, little problem using a Matlab-Function Block in a Simulink Model.
I want one of the inputs to be a structure.
But that doesn't work so easily, I've come across
suggestions on other semi-related problems, which tell about defining Simulink.Bus and so on,
but to be honest I don't understand how this can be applied on my problem.
It seems simple:
Structure as input for a Matlab function Block
But I don't know how.
Sorry for the inconvenience.
Regards BZAD
Within Simulink you create a Bus signal using the Bus Creator Block. This can then be fed into a MATLAB Function block, but only if an accompanying Simulink.Bus object is created in the Base Workspace.
See Types of Structures in MATLAB Function Blocks and Create Structures in MATLAB Function Blocks and the links off those pages for more information.

Sorting an array in Simulink

I want to sort a given array in ascending order. Is there any block in Simulink which does this?
If no, how to do this most efficiently using common Simulink blocks? I understand this could be done using Stateflow but just wanted to know how to do in Simulink.
Thanks!
If you have DSP System toolbox, there is a Sort block available under statistics library. Otherwise you need to use MATLAB Function block as suggested by am304.
Use a MATLAB Function block in conjunction with the sort function. I think that block supports matrix inputs.

RMS not supported in Matlab function inside Simulink

Simulink has a module called "Matlab Function," which allows you to create a custom function in a Simulink flow diagram.
I implemented a simple function in a Simulink Matlab Function module. My function contains a call to Matlab's built-in rms(). When I run the Simulink model, I get the following error:
The function 'rms' not supported for standalone code generation
If I remove rms from my Matlab Function in the Simulink model, the error goes away and the model runs flawlessly.
Questions:
Is there a way to use Matlab's rms in Simulink?
Are there many other native Matlab calls that can't be used inside Simulink?
I just wanted to clarify and expand upon some points made in learnvst's answer.
Even if you are simply trying to simulate a model containing a MATLAB Function block and are not explicitly attempting to perform code generation, you will still get the not supported for standalone code generation error.
As learnvst indicated, there are multiple restrictions on functions that can be used with code generation. However, if you just want to simulate your model, Simulink allows you to do this if you signify these "black-listed" functions as being extrinsic. This lets Simulink know that the functions will be used for simulation purposes only and won't be part of code generation.
In your particular case, add the following line of code somewhere before your call to rms:
coder.extrinsic('rms');
Declaring a function as extrinsic in a MATLAB Function is often useful even when you are performing code generation. For example, you may want to visualize your data using the plot command during simulation, but obviously would not need the plot command to be part of generated code.
Refer to this doc for more info on declaring functions to be extrinsic.
The not supported for standalone code generation part of the error suggests to me that you are trying to use a product like Matlab Coder to make an executable or native code. If this is the case, there are many naive calls that cannot be used directly in both core Matlab and the toolboxes. The coder products only support a subset of the language. More information can be found here . . .
http://www.mathworks.co.uk/products/matlab-coder/description2.html
As for your call to rms, it is only calculating the root of the mean of the squares. Try creating an alternative using something like . . .
sqrt(mean(x.^2))
...where x is the signal.

How can I call an m file in Simulink and put it to a block in my model?

How can I call an m file in Simulink and put it to a block in my model (without using an S function)? Does anybody have an idea? I'd really appreciate it.
If you're trying to apply a user-defined MATLAB function to Simulink signals, there are a few different ways to do this, depending on your objective. All options are available within the User-Defined Functions section of the Simulink library.
Use the MATLAB function block if you intend to generate code from your model. This block does have restrictions, the entire gamut of built-in MATLAB functions is not available.
Use the Interpreted MATLAB function block if you don't care about code generation, this block can make use of any functions.
Use the Fcn block if your m-file is trivial and contains a simple expression operating on the inputs. In this case you can type the expression directly into the block dialog and reference the input / output signals as shown in the documentation.
MATLAB Fcn block is the best solution to embed M-function file into Simulink model. However, be cautious which version of MATLAB you are using, e.g., with later versions of MATLAB Function Block can be implemented with M-function file with %#codegen and C compiler need to be with your MATLAB package. Good luck