Page 676 - ExtendSim User Guide
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650 Analysis
Scenario analysis
Run # Variable 1 Variable 2 5 10 350
6 11 400
Often, however, you want to look at all the possible pairings of the two (or more) variables. In
this example, you would want to run the model 36
times, with the following pairings:
Variable 2
100 150 200 250 ... 100 150 ... 400
Run #
0 1 2 3 ... 7 8 ... 35
Variable 1
5 5 5 5 ... 6 6 ... 11
In order to perform this kind of multi-dimensional analysis, you need to get the values from a file. The most convenient way to do this is to create a file that has two columns separated by a tab character with all the desired pairings. For instance, the file for this example would start with:
5 100 5 150 5 200
In the Sensitivity Setup dialogs for the two parameters, choose Read from file and enter the file name. For the first variable, enter 1 for the column number; for the second variable, enter 2 for the column number.
When you run a multi-dimensional analysis, you usually use a Write block (Value library) to write out the values to examine. In the Write block, select a data destination on the Send Data tab and check Row (or record) index is equal to run number on the Options tab. If the data takes a long time to transmit, you should check Only write to (data destination) at the end of the run on the Send Data tab.
Scenario analysis
Scenario analysis is a method for systemically and strategically examining the outcome of dif- ferent model configurations. The purpose is to support the exploration and analysis of alterna- tives, gaining insight into why your system behaves the way it does and how it can be improved and managed. ExtendSim facilitates scenario analysis through the Scenario Manager
How To

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