Here is a quick summary of how to install MATLAB on Ubuntu 12.04 and create a launcher file for it.
1) Download the software from mathworks.com
2) Once the software is downloaded, don’t continue with the automatic installation. You need to install the software as the root user. Otherwise you will be forced to install the software in your home directory. Run the following in a terminal, replacing the download path to suit your needs:
$ sudo /tmp/mathworks_downloads/R2012a/install
3) Follow the default prompts and activate your software.
4) Get an icon for MATLAB
sudo wget http://upload.wikimedia.org/wikipedia/commons/2/21/Matlab_Logo.png -O /usr/share/icons/matlab.png
5) Using your favorite text editor, create the following launch file and save it as /usr/share/applications/matlab.desktop
[Desktop Entry] Version=1.0 Type=Application Terminal=false Exec=/usr/local/MATLAB/R2012a/bin/matlab -desktop Name=MATLAB Icon=/usr/share/icons/matlab.png
6) You should now be able to find MATLAB from the search menu and lock the icon to the launcher