Simulating Models Using EKL Scripting and Retrieving the Results

You can use EKL (Engineering Knowledge Language) to simulate a model, and then retrieve the results for further use in scripting.

In this scenario, you use the EKL scripting to simulate a model in the first part of the scenario, and in the second part you retrieve results for further use in scripting.

This task shows you how to:

Simulate a Model Using EKL Scripting
Retrieving the Simulation Results for Further Scripting

Before you begin: Do the following to create a library with a model to simulate:

Create a library with the name MyTestLib. See Create a Modelica Library.
In that library, create a model MyModelTest. See Create a New Class or Extend from an Existing Class Using the New Class Command.
Open the model and use the Modelica Editor to insert the following Modelica text:
```
Real x(start=7);
equation
der(x)=-x;
```
See Displaying and Editing Modelica Text for working with the Modelica Editor.
Set up the virtual execution, for example, what algorithm, start time, and stop time to use in the simulation. See Setting up a Simulation.
Note: You can override the start time and stop time in the script.

Simulate a Model Using EKL Scripting

You can simulate Modelica models using Enterprise Knowledge Language (EKL) scripts. You use the global function SimulateBehaviorModel.

In this task, you create an action to simulate the model, and you test that the simulation was performed.

From the Compass, click 3D Modeling Apps , and select Engineering Rules Capture.
From the action bar, click Action .
For full information about actions, see Engineering Rules Capture Users Guide: Working with Actions: Creating an Action.
In the Action Editor, do the following:
1. Click the text pane to enter it.
2. Press Enter to go to a new line.
3. From the tree, double-click MyModelTest.
  
  Important: Use double-click here, avoid entering this part of the line.
  
  `MyTestLib\MyModelTest` is inserted in the text pane.
4. Click Language Browser.
5. In the Language Browser, the Search field, start entering simulate.
  The hits are displayed dynamically as you type.
6. You can see that three functions with the same name SimulateBehaviorModel are available.
7. Click each function to display the documentation window to decide which function to use, depending on if you want to simulate a functional behavior, a logical behavior, or a free-standing Modelica model.
  In this scenario, you simulate a free-standing Modelica model.
8. Double-click the search result SimulateBehaviorModel that is specified for "all Modelica models" in the documentation window.
  ->SimulateBehaviorModel(,) is added in the Action Editor pane.
9. Click in the bracket of the above function and enter the start time and stop time, with comma sign between them.
  Use the start time 0 and the stop time 6 in this scenario.
  
  Note: You can select to use the start time and stop time defined for the model in the simulation setup in Dymola Behavior Modeling. See General Tab.
  
  Important: To select the start time and stop time defined in the simulation setup, you must manually remove the comma sign in the bracket of the function.
  The full text for this task is now:
```
`MyTestLib\MyModelTest`->SimulateBehaviorModel(0,6)
```
10. Click OK.
The result is:
- The action is created.
- In the tree, under the Relations.1 node, the action is displayed with an icon .
In the tree, under the Relations.1 node, right-click Action.1 and select Action.1 object > Run.
In the Insert Object dialog box, click OK.
The result is:
- The action is executed. MyModelTest is simulated with start time 0 and stop time 6.
- The Variable Browser appears to display the result of the simulation.
To check the result, in the Variable Browser, right-click a signal and select Add to Plot > New Plot.
From the Compass, click 3D Modeling Apps , and select Behavior Modeling.

Note: You can now edit and run the action directly without changing app. You can edit the action by double-clicking the action in the tree.

Retrieving the Simulation Results for Further Scripting

You can retrieve the simulation results for further scripting.

In this task, you retrieve the simulation results from the previous simulation, and check that the results were retrieved. You retrieve the simulation results by enhancing the action from the previous task.

Before you begin: Do the previous talk.

To open the action to enhance it, double-click it in the tree.

Tip: You can also right-click the action in the tree and select Action1.object > Definition.

In the Action Editor, do the following:

Press Enter to go to a new line.
To define an EKL variable result of type List where the retrieved simulation results are stored, enter the line let result(List)
On a new line, from the tree, double-click MyModelTest.

Important: Use double-click here, avoid entering this part of the line.

`MyTestLib\MyModelTest` is inserted in the text pane.
Click Language Browser.
In the Language Browser, the Search field, start entering getsimulation.
The hits are displayed dynamically as you type.
You can see that three functions with the same name GetSimulationResult are available.
Click each function to display the documentation window to decide which function to use, depending on if you want to simulate a functional behavior, a logical behavior, or a free-standing Modelica model.
In this scenario, you simulate a free-standing Modelica model.
Double-click the search result GetSimulationResult that is specified for "all Modelica models" in the documentation window.
->GetSimulationResult(,) is added in the Action Editor pane.

Click in the bracket of the above function and enter "x", result to specify the variable result to retrieve, and where to store the information.

Tip: In this case "x" is the variable path, but mostly the path is longer, for example "myCoupledClutches.phi". You can get the path when you simulate the model from the Variable Browser by right-clicking the variable and select Copy path to clipboard. Later you can paste it into the function.

To see all values in the result as a message on the screen, add the line Message("AllValues",result)

The full text for this scenario is now:

`MyTestLib\MyModelTest`->SimulateBehaviorModel(0,6)
let result(List)
`MyTestLib\MyModelTest`->GetSimulationResult("x",result)
Message("AllValues",result)

Click OK.

The action is enhanced.

In the tree, under the Relations.1 node, right-click Action.1 and select Action.1 object > Run.
In the Insert Object dialog box, click OK.
The result is:
- The model is again simulated according to the task above.
- The simulation result of the variable x is retrieved and stored in result for further scripting.
- A message appears, displaying the content in the result.