MATLAB Basics

Description

Availability and Setup

To invoke MATLAB, type: matlab at the shell prompt. You can exit MATLAB by typing exit or quit at the MATLAB prompt.

In general, we recommend that you use MATLAB on the SCV Linux Cluster. Since MATLAB is no longer in development for the AIX pSeries machines, the only working version is MATLAB 5.3.1.

Using MATLAB

The MATLAB Reference Guide lists the primary MATLAB functions in alphabetical order with each command described by purpose, synopsis, description, examples and related commands. For a basic introduction to MATLAB, consider following the Tutorial in Chapter 2 of the MATLAB User's Guide.

Running MATLAB under the Batch System on the IBM pSeries (click here for instructions on the Linux Cluster):

1. Create a script, say, "mbatch", that contains the line:
   

   #!/bin/csh  nohup matlab -display null < $1 >! $2

   On systems that runs MATLAB 6 or 7, you could use the following script:
   

   #!/bin/csh  nohup matlab -nodisplay < $1 >! $2

   Without the "!", output will not be permitted if the output file already exists.

2. type chmod +x mbatch
3. Insert "exit" at the end of your m-file.
4. To run this file, issue the following command at the system prompt:
   

   % mbatch infile outfile

   The above runs the job in the background. Infile is your m-file. outfile is the output file name. Note that Infile must include the suffix .m.
5. To run batch:
   

   % bsub -q queue-name "mbatch infile outfile"

   In the above, queue-name is the queue name.

   You can find out about queue-name by typing, at prompt:

   % bqueues -l

   and find out the status of your jobs:

   % bjobs

6. Run MATLAB without a license:
   If you can't run your MATLAB applications because no MATLAB license is available, here is a work-around.
7. Run MATLAB in parallel:
   If you need to solve large, real, linear system of equations within the MATLAB environment but would like to take advantage of the powers of the multi-processor IBM p690 or IBM p655 systems, you can now use an m-file developed at BU called parallel_lu.m which makes use of LAPACK's LU decomposition linear system solver.

   This m-file calls an external program which in turn calls SGI/Cray parallel math library. To use this, you need to do the following:
   

   1. create a "matlab" directory under your home dir (if it does not already exist).
   2. In this directory, create a file called "startup.m" which has the following line in it:

      addpath /usr/local/examples/matlab/parallel_tools

   3. Run matlab
   4. >> help parallel_lu will give you a description of input/output parameters.
   5. An example, called lu_example.m has been set up and lives in /usr/local/examples/matlab/parallel_tools; you can run it

      >> lu_example

   Please e-mail Kadin Tseng (kadin@bu.edu) if you have problems or suggestions regarding this m-file.

Additional Help/Documentation

What hardcopy documentation we have is available in the Computer Graphics Lab (Room 203, 111 Cummington Street, lab hours and access). This includes a complete set of manuals for versions 5 and 6, including both Getting Started with MATLAB and Using MATLAB.

Online, you may want to visit the site of MathWorks, Inc. the producers of MATLAB and you can get help from within MATLAB using the command help.