User Guide: C++ : Introduction

1. Introduction

CSIM+ is a process-oriented discrete-event simulation package for use with C or C++ programs. It is implemented as a library of classes and procedures which implement all of the necessary structures and operations. The end result is a convenient tool which programmers can use to create simulation programs.

A CSIM program models a system as a collection of CSIM processes which interact with each other by using the CSIM structures. The purpose of modeling a system is to produce estimates of time and performance. The model maintains simulated time, so that the model can yield insight into the dynamic behavior of the modeled system.

This document provides a description of:

• CSIM structures (objects) and the statements that manipulate them
• Reports available from CSIM
• Information on compiling, executing and debugging CSIM programs.

1.1 CSIM Objects (Static and Dynamic)

The C++ version of CSIM provides a number of classes which define the objects CSIM models use. In many cases, you can choose to use either static or dynamic instances of these classes (each instance is an object).

In many cases, it may be preferable to use dynamic objects. The reason for this is that with dynamic objects, you have explicit control over construction and destruction of each object. With static global objects, each object is constructed before the program begins execution and they cannot be deleted. With local static objects, each object is constructed when the procedure starts and is deleted when the procedure exits.

In some CSIM models, the program can use the rerun procedure to "tear down" a model at the end of a run so that a new model can be built for the next run. In this case, dynamic objects must be used.
For this reason, all of the examples in the following sections will use dynamic classes. However, static classes can be used in almost all cases.

CSIM provides the following simulation objects:

CSIM Processes

• processes

CSIM Objects

• facilities
• storages
• buffers
• events
• mailboxes
  

Managing queues of processes

• managing queues

Statistics, collecting data

• Introduction to statistics gathering
• tables
• qtables and qtable_dbl's
• meters
• boxes
• advanced statistics gathering
• confidence intervals and run length control
• process classes
• random numbers

Developing and managing models, output

• output from CSIM
• tracing simulation execution
• miscellaneous
• error messages

Acknowledgements
List of references
Sample program
List of statements, reserved words

It is the processes which mimic the behavior of active entities in the simulated system

1.2 Syntax Notes

• All parameters are required.
• Whenever a parameter is included within double quotes (e.g. "name"), it can also be passed as a pointer to a character array which contains the string.
• Constants, which are represented by names that are entirely in capital letters, are defined in the header file, "csim.h".
  

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