How can I rerun a program with different parameters in Matlab? - matlab

I have a program that simulates a cellular network depending on a certain number of parameters (antenna profiles and so on) and it takes so time to run as I plot many figures.
Do you guys know how I could automatically rerun the program at the end of the script but with the parameters changing automatically to values I would have chosen before ?
Thanks so much for any kind of help ! :)

This is probably not the most elegant solution, but you could try this (assuming i understood te question)
parameters(NumberOfReruns); % fill this with the parameters you want to
% use on each run of the program
for i = 1:NumberOfReruns
program(parameters(i));
end

Related

simulink simulation workspace output values do not change after running simulation from GUI m-file

I am trying to create a matlab gui that simulates a DC/DC converter, and I have succeeded in exporting data from gui to simulink in order to change signal attributes. The problem is that, when I change the values using the gui, the output signals on scopes in simulink change but the signals that I import from the simulation stay the same unless i re-run the simulation from simulink. I am using the evalin function to export workspace data to my m-file. I tried waiting for the simulation to end in order to solve the problem but it didn't.
I hope the question was clear enough and thank you in advance for your help !
Thank you but the problem resided in the command i used to run the simulation and not waiting the proper amount of time in order for the simulation to finish.
To resolve this problem I used the following:
open_system('nameofmodel.mdl')
set_param('nameofmodel', 'SimulationCommand', 'start')
while ~strcmp(get_param ('nameofmodel','SimulationStatus'),'stopped')
pause(1e-99);
end

How do I input variables into a Simulink model through MATLAB script (SimDriveline)

For my coursework project in MATLAB, I have decided to build a drive-line model within Simulink, using the SimDriveline toolbox. The idea is to get the user to input values for the various parameters that are associated with each part of the model, such as the engine or the transmission. I would like to able to write this in a MATLAB script, but I'm not sure how to assign the values that are input to the Simulink model. For instance, the stock sdl_vehicle example that comes with SimDriveline. I am aware of the sim() command, but I am still confused on how to use it properly.
Also at the end of the simulation, the program is supposed to display the graphs that are collected in the scope window. I know that in the window itself that the scope can be printed to a figure, but is it possible to print that scope to a figure through MATLAB script?
This is the first time I have ever used a program like MATLAB. I would appreciate any help I could get, many thanks in advance!
There is a simulink block called simin:
http://de.mathworks.com/help/simulink/slref/fromworkspace.html?searchHighlight=simin
I used it some days back and it worked quite well. You can use the block in your model and define some signals/varibles as input.
After that you may write a Matlab-Script with an input function to set all the previous defined input values.

How to get the iteration number of lsqnonlin

I am doing parameter estimation in matlab using lsqnonlin function.
In my work, I need to plot a graph to show the error in terms of lsqnonlin iteration. So, I need to know which iteration is running at each point of time in lsqnonlin. Could anybody help me how I can extract the iteration number while lsqnonlin is running?
Thanks,
You want to pass it an options parameter setting 'display' to either 'iter' or 'iter-detailed'
http://www.mathworks.com/help/optim/ug/lsqnonlin.html#f265106
Never used it myself, but looking at the help of lsqnonlin, it seems that there is an option to set a custom output function, which gets called during every iteration of the solver. Looking at the specification, it seems that the values optimValues.iteration and optimValues.fval get passed into the function, which is probably the things you are interested in.
You should thus define your own function with the right signature, and depending on your wishes, this function prints it on the command line, makes a plot, saves the intermediate results in a vector, etc. Finally, you need to pass this function as a function handle to the solver: lsqnonlin(..., 'OutputFcn', #your_outputfun).
The simple way to do this would be:
Start with a low number of (maximum) iterations
Get the result
Increase the number of iterations
Get the result
If the maximum iterations is used Go to step 3
This is what I would recommend in most cases when performance is not a big issue.
However, if you cannot afford to do it like this, try edit lsqnonlin and go digging untill you find the point where the number of iterations is found. Then change the function to make sure you store the results you need at that point. (don't forget to change it back afterwards).
The good news is that all relevant files seem to be editable, the bad news is that it is not so clear where you can find the current number of iterations. A quick search led me to fminbnd, but I did not manage to confirm that this is actually used by lsqnonlin.

Share variables between two MATLAB m-files executing separately

I'd like to know if there is something like pointers in MATLAB.
I have two matlab routines which execute simulataneously (that is they are lunched together and run on the same machine, which is, therefore, synchronized in terms of time-stamps).
The first routine, A, has a parfor loop where a data vector is continuously updated. The second routine, B, needs to get access to a specific (but variable in time) row of the vector (of routine A) and do further calculation.
My first guess is to print the updating rows of routine A in a txt file and then get access to it in B when necessary. However, this will result in a large amount of waste time.
I know that this could be related to parallel jobs and scheduler but I dont know how to implement it.
Thank you for any help, guesses or solutions.
Probably this code will help you, if i got correctly your problem. I am waiting for further comments.
Best wishes!

Disable plots in Matlab

I have some programs written in Matlab that I need to run several times for some reasons (debugging, testing with different input, etc...)
But, there are a lot's of graphs that are plotted by the programs and its various functions such that everytime I run the program, I have to wait for all the graphs to be displayed, which is very annoying and time consuming (especially when you are working with a small laptop).
After the program is executed, I close them with a close all.
So my question is:
Is there a way to disable all plots/figures/graphs in Matlab? either in the options, or by executing a certain code like disable plot and enable plot to ensure that no figures are being displayed.
I know that I can just browse the code and comment the plotting part, but I don't want to forget to uncomment.
Try some combination of the two commands:
set(gcf,'Visible','off') % turns current figure "off"
set(0,'DefaultFigureVisible','off'); % all subsequent figures "off"
The second one, if you put it near the beginning of your program, might do the trick for you. Of course, it is still creating the plots, which might be undesirable for computation time and/or RAM issues.
This is a classic reason to avoid Matlab when one can. It fosters bad programming design. To solve this problem correctly, you should create something that lets you "flip a switch" at the highest level of your program and control whether plots show or do not show. Perhaps it even has gradations of the show/don't show option so you can select different types of plots that do/do not show depending on what diagnostics you are running.
Ideally, you'd want this "flip a switch" creation to be a class that has access to visibility and plot functions of other objects. But because interactive object-orientation is so cumbersome in Matlab, it's often not worth the effort to develop such a solution, and most people don't think about this design aspect from the outset of their project.
Matlab would encourage someone to solve this by making flag variables like "isPlotVisible" or something, and creating functions that always accept such flags. I agree this is a bad design.
You could run matlab from the command line with:
matlab -nojvm
but then you don't get the GUI at all. Alternatively, you could write a file 'plot.m':
function h = plot(varargin)
h = [];
end
which doesn't do anything. If this is in the working directory (or somewhere else near the top of the path), then plot will call your function instead of the 'real' plot. You'd need to do the same from any other graphing functions you call.
The closest way I know of 'turning off plotting' would be a folder of such functions that you can add to the path to disable plotting, and remove to enable.
The previous methods are fine, but an easy and good habit to take is to use a "on/off parameter". So basically, at the beginning of your code, you can add something like:
DisplayFigure = 1; %1 = display, 0 = no display
After that, add "if DisplayFigure == 1 ... end" for all your plotting related commands, where the commands should be inside the if statement (the ... above). Hence you won't even compute the plots, which will save you a lot of time and memory. You just have to change the value of the variable "DisplayFigure" to plot or not the figures.