How to create the approximately equal mark in MATLAB - matlab

I want to create the approximately equal mark in the legend of the MATLAB. And it will show correctly, but when I try to export the plot by saveas (gca,'1.eps','psc2'). Then in the file, the approximately equal mark will be error code.

MATLAB legend(), title(), xlabel() and ylabel() functions interpret tex commands by default. A quick search suggests \approx or \cong as possible symbols to try. If it works, could you update your question with before and after examples?
This is what I have in mind
figure
title('Pi \approx 3.14')
or
title('Pi \cong 3.14')
See here for more details of MATLAB tex interpretation.

Related

How can I write with latex character in xlabel in matlab

I would write my xlabel with Latec character so I used this code
x = -10:0.1:10;
y = [sin(x); cos(x)];
plot(x,y)
xlabel('$\mathbb{x}$','Interpreter','latex')
but I have this warning message
Warning: Error updating Text.
String scalar or character vector must have valid interpreter syntax:
$\mathbb{x}$
and the xlabel appear like this
https://i.stack.imgur.com/NCI4n.png
please how I can fix this problem.
The problem with your example is the mathbb command, which is not in base Latex. To show this, replace the \mathbb with, e.g., \mathrm. This will work.
I've never seen an example of adding Latex packages into the Matlab environment. (Update below)
You can have a look at this question, which includes a very aggressive potential way to add the package you need. But it's not clear to me if the solution proposed is actually functional.
How do you use the LaTeX blackboard font in MATLAB?

matlab 2016a simulink graph legend

I have a question about matlab simulink:
Notice just Matlab 2016a simulink because of in old version i can do it but in 2016 version i can't change or set new legend to scope graphs.
help me to do it please.
Thank you
I have 2016b, so I'm not sure I can solve your problem at 100%, but I can give you some examples how to set current names for legend.
First of all turn on the legend property: Scope\View\Legend
Now we can see legend but it has default names. Lets change it!
First method - I can just double left click on it and change it's names. But it is not really good - I can put any signal name even if there is no such names in the simulink model.
We can assign any names to signals in the model:
Another method is to give current names to your blocks - scope shows that names by default. It is informative (so and previous method) because we can easily see where this signal comes from.
Maybe it is what you want.

MATLAB - In FindPeaks, how is 'MinPeakProminence' different from 'Threshold'?

I have written a code in Matlab R2017a, where to detect peaks, I used MinPeakProminence. Now I need to shift the code to Matlab 2014, where MinPeakProminence doesn't exist, while theres in another option called 'Threshold'. But for some reason, it doesn't give out the same results as MinPeakProminence.
How are they both different? What should I be doing to get the same result of MinPeakProminence in Matlab 2014?

Create Matlab figures in LaTeX using matlabfrag or alternatives

I want to include Matlab figures into latex preferably with vectorised formats but with LaTeX MATLAB fonts for all text. I have been using the MATLAB function matlab2tikz which worked perfect for simple figures, but now my figures have too many data points which cause an error. So matlab2tikz is not suitable.
I've been looking at matlabfrag which I think will accomplish what I want, but when I run the script in LaTeX as detailed by the user guide it has an error File not found.
This is my code:
\documentclass{article}
\usepackage{pstool}
\begin{document}
\psfragfig{FileName}
\end{document}
Where FileName is the name of the .eps and .tex that matlabfrag creates. Has anyone come across this problem? Or recommend any other functions/methods to use?
I'm using Texmaker on Windows 7.
My advice would be to rethink your workflow.
Instead of reusing your Matlab code to plot figures and be dissappointed by ever changing outputs with matlab2tikz, start reusing your latex code to plot figures and don't bother about plotting in Matlab anymore (at least not for beautiful plots).
matlab2tikz is just generating latex code based on the latex-package pgfplots. To understand the working of this package is pretty easy, as it is intended to be similar to Matlab.
So why bother and always let matlab2tikz do the work for you? Because again and again you won't be entirely happy with the results. Just try to write the pgfplots-code from scratch and just load the data from Matlab.
Here is a convenient function I wrote to create latex-ready text files:
function output = saveData( filename, header, varargin )
in = varargin;
numCols = numel(in);
if all(cellfun(#isvector, in))
maxLength = max(cellfun(#numel, in));
output = cell2mat(cellfun(#(x) [x(:); NaN(maxLength - numel(x) + 1,1)],in,'uni',0));
fid = fopen(filename, 'w');
fprintf(fid, [repmat('%s\t',1,numCols),'\r\n'], header{:});
fclose(fid);
dlmwrite(filename,output,'-append','delimiter','\t','precision','%.6f','newline', 'pc');
else
disp('saveData: only vector inputs allowed')
end
end
Which could for example look like the following, in case of a bode diagram:
w G0_mag G0_phase GF_mag GF_phase
10.000000 40.865743 -169.818991 0.077716 -0.092491
10.309866 40.345290 -169.511901 0.082456 -0.101188
10.629333 39.825421 -169.196073 0.087474 -0.110690
10.958700 39.306171 -168.871307 0.092787 -0.121071
11.298273 38.787575 -168.537404 0.098411 -0.132411
In your tikzpicture you can then just load that file by
\pgfplotstableread[skip first n=1]{mydata.txt}\mydata
and store the table into the variable \mydata.
Now check pfgplots how to plot your data. You will find the basic plot command \addplot
\addplot table [x expr= \thisrowno{0}, y expr= \thisrowno{3} ] from \mydata;
where you directly access the columns of your text file by \thisrowno{0} (confusing, I know).
Regarding your problem with to many data points: pgfplots offers the key each nth point={ ... } to speed things up. But I'd rather filter/decimate the data already in Matlab.
The other way around is also possible, if you have to few data points the key smooth smoothes things up.

How do I convert Mathematica code into Matlab?

I'm just starting to learn MatLab.
This is what I'd like to convert into MatLab code:
http://postimg.org/image/jqdvcrbod/
Since a lot of my variables are functions or other variables, does that mean that when I write them as functions in MatLab I have to save each of the functions as a separate file? Is there any other way? I don't want to end up with a million separate files, but as of right now, if I write more then one function in the editor, it starts getting confused and doesn't recognize the second function.
Also, is there a way to use actual symbols (like the square root symbol instead of writing "sqrt()") like in Mathematica? I feel like long equations (like the last one) are easier on the eye that way, but that's purely aesthetics.
Is there a way to have MatLab output unassigned variables? Like in Mathematica, if I have y(x) = 2x, if i don't put anything for x, it just outputs 2x.
One quick way to do is use a package in Mathematica called ToMatlab (I attached the download link). It is able to convert Mathematica symbol syntax to Matlab .m file.
Hope this would help.