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On what machines Matlab should be run: cities and moods. You are not allowed to run it on vostok because of its gateway functionality.
There can be three reasons for Matlab not to start:
If “koko” is misbehaving and you need Matlab, of if all five licenses are taken and nobody would close their session, or if you need toolboxes we don't have, you can use the university's machines. Here's how.
The ”-nosplash -nojvm” options will make Matlab start and run faster. It works without them too, if you like the luxury of a GUI. Among the remote machines above, “tree” was the fastest, but maybe I just caught it in a good mood.
The remote machines see your directory on the Leland systems. To transfer files to and from the current SEP system directory to the Leland directory, use sftp from koko or from your local machine:
After you started sftp, use “put” to transfer a file from the SEP current directory to the Leland systems home directory: “put <filename>” , and “get” to retrieve a file: “get <filename>” .
You can also use “scp <files_here> <username_there>@<machinename>:<path_to_files_there>”, either from the local machine to the remote one, or the other way around.
If you need to read/write SEPlib format files from Matlab when running Matlab outside the SEP computing system, download the I/O toolbox and unarchive it with “tar -xvzf toolbox.tar.gz” or copy it from /usr/local/matlab7/toolbox/nick/. Let the Matlab Administrator know of any bugs, he'll appreciate the feedback. Solving them, or extending the capabilities of the toolbox to handle other OSs than Linux are even more appreciated.
can be found at www.mathworks.com/access/helpdesk/help/helpdesk.shtml. It is much richer than the simple line-of-command help, it has examples, pictures, and tutorials on how to use each of the toolboxes. The search feature is also quite useful, it searches through their pdf documents and through the user-posed questions, too.
In the SEP reproducibility denomination system, Matlab figures are considered Conditionally Reproducible because they require a proprietary software package (“matlab”). There are two degrees of reproducibility:
PROBLEM:On the new Matlab 6.0, when running a command such as surf, that produced a 3D display, the thing would take a huge time to display, or would crash, and sometimes the following error would appear:
”Xlib: extension “GLX” missing on display “nada.Stanford.EDU:0.0”.
??? Not able to create a render context” .
SOLUTION: If before running your surf command you run: “set(gcf,'renderer','zbuffer')”, the 3D image will display correctly and very fast, too.
Add the following line line before outputting the tiff file, and make sure to run 'xhost + ashland' on santorin console before creating the figure.
Recently, I gave Matlab a job that required it to go through roughly 400 iterations. The job involved adding some numbers into a big matrix, nothing complex. To my surprise, after 10 hours, it still had not finished running.
I had matlab display a iteration counter. The speed of iteration slowed down fast after the first iterations, and I knew there were no convergence problems, so Matlab was sabotaging itself. I included the coomand ”pack” inside the loop, and the program executed in five minutes what previously had not been able to do in 10 hours!
Matlab Digest describes how to export figures for publications in a reproducible, automatized manner. Links to part 1 and part2 of the article. The functions they provide (“exportfig”, “previewfig”, “applytofig”, “restorefig”) are now installed on koko too. The Technical Support Guide to Printing is a good resource too.
Matlab already handles naturally simple LaTeX encodings that allow introducing Greek lettters or modifying the font size and appearance in plots. The function "teximage" (now installed on ashland too) converts any LaTeX string to images and displays them in Matlab figures.
The function “noise.m”, now installed on ashland too, adds Gaussian, uniform, salt and pepper, additive or multiplicative noise to an image.
Sometimes you may want to run scripts which contain plotting commands without displaying the plots and without going into the script to comment out the commands. An example: if you're working from home and it's too slow to run graphics over the network. You can play a simple UNIX trick:
” % setenv DISPLAY /dev/null
% matlab “