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## Very simple question for beginner

### Very simple question for beginner

Hello,

I know, Google is my friend, but i don't find the answer to a very simple question How can I build a "model" (in fact it is not a model) to simulate an equation.

For exemple :
x = 0,5.a.t² in function of a.

How can I see the influence of the variation of the parameter "a" in only one graph.
I'd like to have, in one graph, the simulation for a = 5, a = 10, a = 15, a = 20

Is my question clear enought ???

Do you have a link for a documentation, a video ???

Thank you very much !
Guillaume

guillaumemartin59  2 Posts

### Re: Very simple question for beginner

Something like this.

#### Code:

```package MyFirstPackage

model ReuseModel
Real x(start = 0, fixed = true); // change the start value if you need to
parameter Real a = 5;
equation
x = 0.5 * a * (time ^ 2);
end ReuseModel;

model RunSeveral
ReuseModel f1(a = 5);
ReuseModel f2(a = 10);
ReuseModel f3(a = 15);
ReuseModel f4(a = 20);
end RunSeveral;

end MyFirstPackage;
```

Then you can either simulate model ReuseModel, plot x, change a = 10 in the plot view, right click on the simulation results, say resimulate and simulates with a = 10, 15, 20.

Or you can simulate RunSeveral and plot f1.x, f2.x, f3.x, f4.x on the same plot.

https://paste.pics/7f3948ee0531f8eb470b46df86aa0d06  885 Posts

### Re: Very simple question for beginner

Thank you I'll try

guillaumemartin59  2 Posts

### Re: Very simple question for beginner

Then you can either simulate model ReuseModel, plot x, change a = 10 in the plot view, right click on the simulation results, say resimulate and simulates with a = 10, 15, 20.  