I'm just a beginner in racket and I'm trying to write a function that takes a distribution and displays a graphical representation of the histogram. Is anyone able to help me out?
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I'm doing a tutorial to learn matlab and simulink, and it came to a part where you run the .slx model from the script and extract data from it. The issue is that my matlab doesn't offer the same options for a dataset compared to the tutorial, specifically the get.Element option
picture to make it clearer:
enter image description here
I am aware that .p files are Matlab protected files. So, I am not trying to access them. However, I was wondering if I could use their output onto the Matlab shell as input to a Matlab program.
What I mean is the following: I have to simulate a dynamic system in Matlab using a controller. Afterwards, I need to assess its performance. This is done by the .p file. Now, the controller behaviour is defined by six distinct variables. I pretty much know their range. So, what I did was create an optimization to find the optimal coefficients. However, when I run the .p file I see that the coefficients I obtained as optimal are in fact not optimal, i.e. my cost function is biased in some way.
So, what I would like to do is to use the output of the .p file (there are always six strings with only two numerical values - so they would be easy to extract if it were a text file) to run a new optimization so that I can understand what I did wrong in my original cost function.
The alternative is finding the parameters starting from my values by trial and error, but considering there are six variables I would prefer a more mathematically pure approach.
Basically, the question is how I can read the output onto the command prompt of a Matlab .p function, and use it as input in a Matlab function.
Thanks for the help!
I am using a Matlab function block in Simulink model. In my case, the Matlab function block takes in an arbitrary number of signals as input signals and outputs signal values over time in the form of a histogram.
I need a little guidance regarding how to start with matlab function block coding. I have read the documentation and various other posts but could not work my way around it, probably because its a new topic for me and i am not a matlab programmer. Any help in this regard is appreciated.
Thank you.
I am trying to simulate a time series process using Matlab. For example, let's see the following example:
http://www.mathworks.com/help/econ/arima.print.html
When I run following code
model = arima(1,0,1);
[fit,VarCov] = estimate(model,Y,'print',false);
I get the following error:
??? Undefined function or method 'arima' for input arguments of type 'double'.
Does Matlab contain functions for Matlab? Can I calculate different functions,like calculate autocorrelation or autocovariance at different lag? Or estimate ARMA parameters?
You need to make sure that you have a license and code for the Econometrics Toolbox before using that function. MATLAB has annoying license requirements for both the main software and its various toolboxes :(
But, you may be able to find some public code that can do the same thing. Check out http://www.mathtools.net/
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.