SIMSCRIPT II.5 Programming Language

Contents
3.5.3 Repositioning Files ............................................................................................121
3.5.4 Input/Output of Nondecimal Information ...........................................................121
3.6 INTERNAL EDITING OF DATA ................................................................... 122
3.7 WRITING FORMATTED REPORTS ............................................................ 124
3.7.1 Page Heading Control .......................................................................................136
4. MODELLING CONCEPTS................................................................................. 137
4.1 INTRODUCTION ....................................................................................... 137
4.2 ENTITIES AND ATTRIBUTES ..................................................................... 137
4.3 SETS ..................................................................................................... 139
4.4 TEMPORARY ENTITIES ............................................................................ 144
4.5 PERMANENT ENTITIES ............................................................................ 147
4.6 SYSTEM ATTRIBUTES ............................................................................. 149
4.7 ATTRIBUTE DEFINITIONS: MODE AND DIMENSIONALITY ........................... 150
4.8 SETS: THEIR DECLARATION AND USE ...................................................... 151
4.9 ENTITY CONTROL PHRASES ................................................................... 164
4.10 COMMON ATTRIBUTES .......................................................................... 168
4.11 COMPOUND ENTITIES ............................................................................ 170
4.12 IMPLIED SUBSCRIPTS ............................................................................ 172
4.13 DISPLAYING ATTRIBUTE VALUES ............................................................ 174
4.14 SOME SAMPLE PROGRAMS ................................................................... 176
4.14.1 An Inventory Control Example ....................................................................... 176
4.14.2 A Data Analysis Application ...........................................................................178
4.14.3 An Analysis of Prime Numbers ......................................................................181
4.14.4 Dynamic Definition and Use of Attributes .......................................................181
5. DISCRETE SIMULATION CONCEPTS ................................................................ 183
5.1 INTRODUCTION ....................................................................................... 183
5.2 DESCRIBING A SYSTEM MODEL .............................................................. 183
5.2.1 Event Declaration............................................................................................. 187
5.2.2 Event Notices ...................................................................................................188
5.2.3 Process Declaration .........................................................................................189
5.2.4 Scheduling Events and Processes ..................................................................190
5.2.5 Processes and Events Scheduled for the Same Time .....................................191
5.3 THE SIMULATION MECHANISM ................................................................ 193
5.3.1 The Simulation Clock .......................................................................................195
5.3.2 Assigning Event and Process Attributes ..........................................................197
5.3.3 Process Interactions ........................................................................................ 200
5.3.4 Interrupting and Resuming a Process ..............................................................201
5.3.5 Processes and Resources ...............................................................................202
5.3.6 Requesting and Relinquishing Resources ....................................................... 203
5.3.7 Process Notice: Additional Attributes ..............................................................205
5.3.8 External Processes and Events ....................................................................... 207
5.3.9 Triggering Processes and Events Externally ...................................................209
5.3.10 Time and Date Expressions in External Data .................................................210
5.4 MODELLING STATISTICAL PHENOMENA .................................................... 214
5.4.1 Random Step Variables ...................................................................................220
5.4.2 Random Linear Variables ................................................................................ 220
5.4.3 Programmer-Defined Random Variables......................................................... 221
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