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SimQuest 6.4 help

 

 

Getting started - Step 1: A Model

 

There are different types of models in SimQuest, but for now you will only work with an Equation model. Equation models consist of a number of typed equations. You are going to add two equations to the model:

 

y = a * x contains a single output variable (y) and two input variables (a and x). 
dx/dt = 1 makes the model dynamic: the value of x is equal to every time step t, meaning that
if t is raised with 1, x is also raised with 1

 

1.1  Adding a model to the application

First, an empty model has to be added to the application. Act as follows:

 

1.From the Library (the list with elements on the left of your screen), drag and drop a New Equation model into the All Elements folder of the Application window (the right part of the screen). A new tab sheet, called 'New Equation Model', should appear in your application.

       

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Dragging a New Equation Model into the application.

 

2.Select the tab sheet New Equation Model.
3.Select the element New Equation model.
4.Right click and choose Edit from the menu (see the figure below). The Equation editor opens.

 

       getting_started1a

       Editing a New Equation Model.

 

1.2  Adding the first equation

Now you can add equations to the Equation Model. These equations form the basis of the learning environment. Like all equations, the equations in an Equation model consist of independent input and dependent output variables. In the equation y = a * x for instance, y is dependent of the input variables x and a. Let's enter this equation in the equation editor:

 

5.In the area on the right of the Equation editor, type the equation: y = a * x
6.Click Accept.

 

       getting_started3

       Entering the equation y=a*x in the Equation editor.

 

You will see that the three variables a, x and y have appeared in a list on the left. Two of these, both input variables, are red. This is because no initial conditions were yet specified. This step is necessary to be able to run the model later on. Therefore, select the variable in the list on the left, and type an initial value in the value box at the bottom of the editor.

 

7.Give a the value 3 and x the value 0.
8.Click Accept.

 

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       Specifying an initial value for an input variable.

 

You can now continue adding as many equations as you like. You do not need to use single letters for variables. You may for instance also use: variable1 = variable2 + variable3.

 

1.3  Making the model dynamic

The model you have created in the steps above is static. This means that none of the values of the variables changes with time. You are now going to turn the static model  into a dynamic one, in which x will be a function of time.

 

9.Add this line to your model to make it dynamic: dx/dt = 1        
10.Click Accept.

 

Now x becomes a state-variable and t a time variable. SimQuest solves x for every time step numerically. Since the increment is simply equal to one, x will always have the same value as the time variable t. After you added the new equation to your model, click Accept. Then:

 

11.Give t the initial value 0.
12.Click Accept.

 

Your model is now complete: you can move on to Step 2 and start to work on your first interface.

 

>> Continue to Step 2: Interfaces

 

 

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