1:how to use events 2:how to put a sine input

Hi,

I´m modeling with Simbiology a big pathway with a constant input(A protease for example). The modell works great. The problem comes when I try to make a sinusoidal input:

 1:How does the events tool in simbiology work?

   I would love to see some easy example. This way I would be able to make at list a step function input. I have seen that some of you already asked about it, but it didn´t clarify me very much.

 2:¿Isn´t it possible to select any function to use as input into the model? ¿Are events the only way to define such inputs?

Thanks in avance, Willy

Answer 1

[Marc]

The example "Creating a Model that Changes a Species Amount Using an Event" shows how to introduce a step change in a species. It is in the documentation here: example

Events are discontinuities and therefore cannot be used to drive a species with a sine wave. However, you can use a rate rule to do this to make the species named 'x' in modelObj vary sinusoidally.

addrule(modelObj, 'x = cos(time)', 'rate');

This creates a rate rule that specifies dx/dt = cos(time) which, when integrated, will mean that x is sinusoidal. You may also need to set x as a boundary condition depending on how it is used in your model. I suggest the following sections of the documentation for further information on species and rules: Species and Rules

-Marc