Using AMPL/CPLEX at UCSC

This is just some quick, dirty documentation on using AMPL from within the TIM department at UCSC.  There may be holes in this information--if you find it lacking or downright wrong, please send me an email.

Steps:

1. Have an account on the TIM network.  If you don't have one and think you should, I think talking to one of the TIM-associated professors is the right way to get one.

2. Log into tim1 via ssh.

3. Set the necessary shell variable ILOG_LICENSE_FILE to /usr/ilog/ilm/access.ilm  (depending on your shell, you do this in slightly different ways).

4. Now you should be able to use the tools in the /home/ILOG/ directory.

5. To make things easier on yourself, you may want to add the appropriate directories to your PATH (PATH=$PATH:/new/directory:/another/directory:/etc/etc)

6. Steps 3 and 5 will be handy to have in your shell startup script (.bashrc or .cshrc I think).

Some notes:

1. The key is specific to tim1, no other machine will allow you to use the AMPL/CPLEX tools.

2. The key only allows one user at a time, thus be mindful of the time you spend using the tool.  On that note, for debugging your models and data, there is a great free tool called NEOS that will allow you to run your ampl models for free.  Depending on the solver, there may be restrictions on the runtime and/or memory usage.  You could download the trial student version of AMPL.  The trial version has limits on the number of variables and constraints, but that's just for solving.  You can load up any size problem and use the tool as a syntax checker.

3. There is documentation in the /home/ILOG directories for AMPL, CPLEX, concert (all the tools for which we have a license).  UC Berkeley has all of that documentation online.