MATLAB

MATLAB
Matrix Laboratory Software

Version	R2014a on UNIX R2014a (or newer) for download
Vers. Date	2/11/2014 for R2014a
Download	On Unix OIT for Faculty/Staff
Cost	Free on UNIX
Manufacturer	MathWorks
Web Page	http://www.mathworks.com
Pundit Updated	8/23/2014

MATLAB is a MATrix LABoratory program that can be used to load, process, generate, present, and analyze numerical data.

FAQ

MATLAB gives me the splash screen, then just sits there...

• Go to a terminal window and type "ps -u NETID" with your NET ID. There should be a process called "matlab". Get the number off it, then type "kill -KILL NUMBER" (the adverb really is "-KILL"). Then, go to your root directory, change into the .matlab directory and remove the contents with "rm -ir *" (make SURE you are in the .matlab directory). Go back to where you were and start matlab again.

MATLAB on Unix just sits there - I think I created an infinite loop! Or I am running a program that will take a significant fraction of forever to complete...

• Go to a terminal window and type "ps -u NETID" with your NET ID. There should be a process called "matlab". Get the number off it, then type "kill -KILL NUMBER"

MATLAB on Windows just sits there - I think I created an infinite loop! Or I am running a program that will take a significant fraction of forever to complete...

• Hit CTRL-C to break out of Matlab.

How do you even get IN to MATLAB? I have no idea...

• After logging in to an OIT machine (or using MobaXterm to get there from a PC , or using X11R6 on a Mac to log in) just type matlab & at the command prompt.

How do you type MATLAB code in these pages, and how do you make it pretty?

• The SyntaxHighlighting extension is installed on this wiki, so all you have to do is use the appropriate source and lang tags. The code:

<source lang="matlab">
%% Post-processing
% take data from AI
[data, time] = getdata(AI);
%% plot data 
c1 = data(:,1); c2 = data(:,2); c3 = data(:,3); c4 = data(:,4);
plot(time, c1, 'b-', time, c2, 'g--', time, c3, 'r-.', time, c4, 'c:')
legend('0', '1', '2', '3', 0)
xlabel('Time (s)'); ylabel('Voltage (V)');
</source>

produces

%% Post-processing
% take data from AI
[data, time] = getdata(AI);
%% plot data 
c1 = data(:,1); c2 = data(:,2); c3 = data(:,3); c4 = data(:,4);
plot(time, c1, 'b-', time, c2, 'g--', time, c3, 'r-.', time, c4, 'c:')
legend('0', '1', '2', '3', 0)
xlabel('Time (s)'); ylabel('Voltage (V)');

See the page linked above for other languages that are parsed.

How do I change colors and fonts?

In the File menu, pick Preferences and, in that window, look three different places:

1. The Fonts section allows you to change fonts. Make sure to choose a monospaced font.
2. The Colors section allows you to change most of the colors. Pay careful attention to the sample color block in this window to make sure you can read all the different colors of text.
3. The Editor/Debugger section has a Display subsection - this is where you can control the color of the current line (the default is not to alter it) as well as the color of a highlighted section (i.e. a segment of code under a %% comment)

How do logical masks work?

• See the Logical Masks page in the MATLAB name space.

What do the line number mean on the CB-68LP card?

• See the CB-68LP_Pinout page in the MATLAB name space.

How can I use inline functions?

• See the Inline Function page in the MATLAB name space.

How can I use anonymous functions?

• See the Anonymous Function page in the MATLAB name space.

How do I define a function in a text file?

• See the User-defined Function page in the MATLAB name space.

How do I run MATLAB without the GUI?

When attempting to use MATLAB on a Teer machine when you're not at Duke, it's often easier to refrain from opening the GUI (which can be too slow). Here are some steps around that.

1. SSH into teer machine
2. Navigate to directory with MATLAB Script
3. Ensure MATLAB Script has the command 'exit' on its last line
4. type 'which matlab' into the command prompt, which should output something like /usr/bin/matlab
5. Assuming the output is /usr/bin/matlab, enter '/usr/bin/matlab -nosplash -nodisplay -nodesktop < fileToRun.m > outputFile.txt' into command prompt
6. Open outputFile.txt by typing 'cat outputFile.txt' into the command prompt. This will allow you to see the text output of the MATLAB file.

Note: If you want to view images, type the "print -dpng 'figureToView.png';" command after each plot in your MATLAB script. A .png file will be saved in the same directory after compilation.

Questions

Post your questions by editing the discussion page of this article. Edit the page, then scroll to the bottom and add a question by putting in the characters *{{Q}}, followed by your question and finally your signature (with four tildes, i.e. ~~~~). Using the {{Q}} will automatically put the page in the category of pages with questions - other editors hoping to help out can then go to that category page to see where the questions are. See the page for Template:Q for details and examples.

External Links

• The MathWorks: Main Page, Support Site, Academia Center, Classroom Resources (includes topic- and department-specific subpages)
• softscope help page at The MathWorks
• Paper on Introducing Computational Methods to First-Year Students with Diverse Skills and Interests, Michael Gustafson, August, 2007