eXTReMe Tracker

Turn off system beep in Linux

 Linux and OSS  1 Response »
Feb 102009
 

The system beep is one of the most distracting and annoying occurrences when you are doing some constructive work. Be it working in a text editor, or a terminal, or a program window – wherever a sound notification is programmed into any module, it emits a fairly audible beep. To disable the beep, we have to disable the PC speaker by adding it to the blacklist.

sudo gedit /etc/modprobe.d/blacklist

Add the following line to the end of that file:

blacklist pcspkr

Save and exit. Then in terminal,

sudo modprobe -r pcspkr

This completely turns off the speaker. You won’t hear your system beep, even if there is something truly wrong. If you are doing something critical and need to rely on the beeps, comment out the line from the blacklist and run the modprobe command. Beeping will restart.

Installing Matlab 2008b on 64-bit Linux

 Imaging, Linux and OSS, non-OSS  No Responses »
Feb 102009
 

Recently I bought a student version of Matlab2008b. It was for Linux platform. Here’s my experience with installing the program on 64-bit Linux (Debian) architecture, what problems arose along the way and how they were addressed – with help from Mathworks tech support.

Matlab at work

Matlab at work

Installing Matlab 7.7 (i.e. Matlab2008b) the old fashioned way was a breeze, but getting it to actually run on 64-bit architecture involved a few steps, which I didn’t know. I sent a query to Mathworks tech support saying:

The installation files were able to successfully install Matlab2008b on Ubuntu 9.04 (Jaunty), however, the program failed to load since it cannot find the jre files for 64-bit architecture. Is there a workaround for running the 32-bit program on 64-bit platform?

And they replied with a procedure to be followed to make that happen:

Yes – here is a full walkthrough:

1) When running the MATLAB installer (install_unix.sh) use the -glnx86 flag.  This will allow it to install properly on a 64-bit Linux machine:

./install_unix.sh -glnx86 -t

2) Once the installer is finished, you will need to activate through mathworks.com, as the activation client will not work properly on 64-bit computers.  To do so, follow the instructions below:

http://www.mathworks.com/support/solutions/data/1-3YZBZ6.html?solution=1-3YZBZ6

3) Once MATLAB is installed and activated, you will need to run MATLAB using the same -glnx86 flag that you used to install:

$MATLAB/bin/matlab -glnx86

(where $MATLAB is the MATLAB installation folder)

NOTE: Some users have problems loading the JRE when running in this configuration.  Creating a symlink in $MATLAB/sys/java/jre named glnxa64 pointing to glnx86 should resolve this issue.  You can do this with the following command:

ln -s $MATLAB/sys/java/jre/glnx86 $MATLAB/sys/java/jre/glnxa64

And now it works. Haven’t had any GUI crash on me yet, but it been less than an hour since I’ve been using it. One way to avoid typing matlab -glnx86 before each launch is to create a local alias.

gedit ~/.bashrc

Under one of the listing for aliases, you can type in:

alias mat='matlab -glnx86 &'

Save and exit. Then onward, you can launch the program by simply typing in mat in the terminal.

In case your compiz is enabled, you might not see the menus correctly. To fix that problem, you have to run the following command at the terminal.

export MATLAB_JAVA=/usr/lib/jvm/java-6-sun/jre/