Page 673 - ExtendSim User Guide
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Analysis 647
Sensitivity analysis
So that you don’t overwrite the original model, give the command File > Save Model As and save the model as “Sensitivity”.
Open the dialog for the Random Number block labeled “Stream”.
Open the Sensitivity Setup dialog by doing one of the following to the Maximum entry field:
• Clicktheentryfieldandchoosethecommand Edit > Sensitize Parameter.
• Or right-click the entry field and choose Sensi- tize Parameter.
• Or click the entry field while holding down the Control (Windows) or Command (Mac OS) key.
The Sensitivity Setup dialog appears with the Enable sensitivity checkbox selected by default.
Enter Set Simulation Setup to: 4 runs.
☞ The number of runs can be set in either the Sensi- tivity Setup dialog or the Simulation Setup dialog. Each controls the other so that the last value selected in either of them controls the number of runs.
Enter Starting at 1 and change by 0.5.
This will cause the stream’s flow to increase by
0.5 for each subsequent run.
☞ Parameter values can be sensitized using values
from a file, a specified range of values, a random
distribution, or values from a database.The
choices are described in “Specifying the sensitivity method” on page 648.
Sensitize Parameter menu
Sensitivity Setup dialog
Close the Sensitivity Setup dialog.
In the Random Number block’s dialog, the parameter field now has a green border around it, indicating that it has a sensitivity setting and sensitivity analysis is active for the parameter.
Add a Plotter, MultiSim block (Plotter library) to the right side of the model and add a Contents named connection to its input.
This plotter displays up to four runs of data on a sin- gle graph, so you can see what impact changing the stream flow has on the contents of the reservoir.
Sensitized parameter
Model with Plotter, MultiSim
How To

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