Page 685 - ExtendSim User Guide
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• A database variable is a variable that references an entire database or a subset of a database, such as a database table or field.
• Asourceisadatabasevariablethatgetscopiedtoatarget
• Factorsourcesarethesetofvaluesthatadatabasevariablecantakeforallthedifferent
scenarios. They contain all of the information for all of the scenarios.
• Aresponsesourceisthevalueofadatabaseoutputvariableforaparticularreplication. Each response source only has the information for the current set of replications.
• Atargetisadatabasevariablewhosevalueisdefinedbyasource
• Afactortargetisadatabaseinputvariablewhosevaluehasbeendefinedbyaparticu- lar factor source. Each factor target only has the information for the current set of sce- nario replications.
• Response targets are a collection of output database variables where each variable’s value is defined by a particular response source. They contain all of the results for all of the scenarios.
• The architectures of the targets and the sources must match. For example, if the source is a database table, the target must also be a database table with the same number of fields.
• Aminimumnumberofsourcesandtargetsmustbecreatedforthemodel:
• For database factors, at least two sources and at least one target. (Each set of data is a source so having one source does not make any sense when there are sets of data.)
• Fordatabaseresponses,onesourceandanumberoftargets.Thenumberoftargets depends on whether ExtendSim creates the source and targets or you do it manually. If Auto-Create Target is selected in the Database Responses table, ExtendSim will create a new database target for every simulation run. If manually, create one source and one target per scenario.
• IfyourunthemodelfortestingpurposeswithoutusingtheScenarioManager,theidentified variables can be used in the model. However, these variables are just placeholders and their contents will change when you use the Scenario Manager.
• Factortarget.Whentestingthemodel,usethetargetdatabasefactorinyourblocks. (Either link a parameter or data table to the target variable or use a Read or Write block to reference the target variable.)
• Responsesource.Similarlytotheabove,buildthemodelasifyouwillbeusinga placeholder database response variable. However, use the source rather than the target.
• Sourcesarealwayscopiedtotargets.Whenandhowthishappensdependsonwhetherthe database variable is a factor or a response.
• Factor.Atthestartofeachsetofscenarioreplications,theScenarioManagercopies the contents of the source database factor variable into the target database factor vari- able. This is done automatically by the Scenario Manager.
• Response.Attheendofeachsimulationrunthedatabasevariablesusedinthemodel are copied from the source to the target database variables for that scenario.
Analysis 659
Scenario analysis
How To

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