Department of Computer Science and Engineering
Computer Science 177: Simulation and Modeling
Spring 2003
Course Information
Sample Midterms and Exams
These notes describe the development
of a "gas station" model as a detailed example of an event-driven simulation
program. Beware that this example program is written in an obscure (but vastly
underappreciated!) programming language called Turing. However, this same "gas
station" program was later translated into several other languages that
you may be more familiar with, namely:
Information about Programming
with CSIM
CSIM is an extension to C++ (or
to C, since there are two versions available) with special features to make
it easy to write simulation programs, including the generation of random
variables with many commonly used distributions and a variety of built-in
measurement constructs. Unlike "conventional" methods for programming an
event driven simulation model (i.e, the time-driven or event-driven program
structures) CSIM models rely heavily on concurrent programming techniques
(similar to what you may have seen in CS153 and/or CS160), which in the simulation
literature is known as the process-interaction
method for constructing a simulation model. What this means to you is that
you must write a self-contained "program" (more properly a "process" or
"thread") to describe the behavior of a single entity. The combined
behavior of the simulation model is obtained by the magic of concurrent execution:
we assume that each of the active entities are executing their respective
"programs" concurrently, using the simulation clock and/or various
inter-process communications programming constructs (such as
signal/wait, mutual exclusion, etc)
to coordinate their activities.
CSIM Reference Manual
The complete CSIM reference manual
is available online at the Mesquite Software website here.
Using CSIM on CS Department Computers
This information has been updated
following the installation of CSIM-19 in April 2003. The CSIM-19 installation
package comes with many small example programs to illustrate the use of different
language features. On the CS Department computers, they can be accessed
through the directories:
| /usr/local/pkgs/csim19/c++/examples |
For C++ versions of the example CSIM programs |
| /usr/local/pkgs/csim19/c/examples |
For C versions of the example CSIM programs |
CSIM/C++ programs can be compiled
on the local CS department computers with the following one-line command or, if you prefer, a Makefile set up for the airport shuttle example
below.
Large Sample CSIM Program - Airport
shuttle bus system
Here
is a CSIM program that simulates the shuttle bus to connect the airport terminal
buildings with an offsite rental car center.