Once you have a model where you’re getting an optimal solution that makes sense for one set of inputs or parameters, it’s often useful to vary one or more parameters across a range of values, and find the optimal solution for each individual parameter value. With Analytic Solver Platform, you can easily define optimization parameters, run multiple optimizations and save the solutions to each optimization, and summarize the results in reports and charts.
Imagine that you wanted to use an optimization parameter to vary the value of the right hand side of an existing constraint from 10 to 15. To define the optimization parameter, you would select an empty cell and choose Parameters – Optimization from the Ribbon. Analytic Solver Platform will display a dialog asking you to enter a lower and upper limit for the parameter value, or alternatively a list of values or a cell range. In this instance, you would enter 10 for the lower bound and 15 for the upper bound, then click OK. The formula =PsiOptParam(10,15) would appear in the cell. If you wanted Solver to increment the constraint right hand side by 1 unit on each solver, you must set the number of optimizations on the Platform tab of the Solver task pane to 6. In the first optimization, Solver would set the right hand side of the constraint to "10", in the second optimization - "11", "12" in the third optimization, "13" in the fourth optimization, "14" in the 5th optimization and "15" in the sixth optimization. Now you can simply click the Optimize button on the Ribbon, or the green right arrow on the Task Pane, to run all 6 optimizations at once.
By default, Analytic Solver Platform saves the optimal objective and decision variable values from all 6 optimizations; you can save other results, such as constraint values, by setting their Monitor property in the Task Pane to True. Just after solving, Analytic Solver Platform displays the results of the last optimization on the worksheet. But you can display the results of any of the other 6 optimizations by selecting from the Opt # dropdown list on the Ribbon:
Analytic Solver Platform has built-in facilities to create reports and charts of multiple parameterized optimizations. To create a report recording the value of the optimization parameter and any monitored cells, select Reports – Optimization – Parameter Analysis. To create a chart illustrating the same, select Charts – Multiple Optimizations – Monitored Cells.