Scenarios are used for running a sequence of simulations.

Examples of where scenarios are useful:

• Running simulations where the model is the same but the inputs vary. For instance, a model for the metabolism of substance in the human body can be run for different sets of exposure parameters.
• Running simulations where the main model is the same, but the values of some expressions or general variables differs. For instance, running a model calculating the doses of a population where the dose expressions depend on different age groups or gender.
• Testing solver settings. The same model is run several times but with different simulation settings.

Scenarios are defined and listed in the scenario window. This window also allows you to override the simulation settings for specific scenarios.

In order to specify equations or values which are specific to a scenario, you must make the required blocks scenario dependent by assigning them a scenario index list. The individual values can then be specified by editing the objects directly.

To run a sequence of simulations using scenarios, perform the following steps.

1. Create or open a model.
2. In the scenario window, create and name each scenario.
3. (Optional) Edit each block which requires values specific to a scenario. Add a dimension to the object and specify the scenario index list for the new dimension. Then write the equations/values specific to the scenario in the same window.
4. (Optional) In the scenario window, edit the simulation/probabilistic/sensitivity analysis settings by clicking the corresponding button in the list.
5. In the Simulation Menu, select Scenarios
6. Start the simulations by clicking the button on the toolbar.
7. The Results window will list all the outputs of the simulation, grouped by scenario.

When a scenario is created in the scenario window, an index is automatically added to the scenario index list. To make a block dependent on scenario, you assign this (or an index list which is a sub-set of or mapped to it) index list to a block. Adding this index list to an object does not change the dimension of the block - the block can still be used by objects which are not dependent on scenario. Assign values that are not scenario specific by using the default rows/columns.

• Tutorial 8-Scenarios
• Index list