Re: Defining fixed variable for a certain time

[fredomatic]

Hi!

If you just need to use a state or "output" value at time zero, then
yes, that is possible, because that value can be computed in Initialize
and assigned to a parameter there. Then you would us that parameter.
If you want to use a state or "output" value at a time t different from
zero, you would have to define what happens before that time, and you
would have to record somehow its value at time t. You can try using
Events() but they maybe too restricted. An alternative is to use
Inline() code to catch the value at time t. You must make sure that the
integrator evaluates Dynamics{} or CalcOutputs{} at time t. The best
would be to define an output time, even if dummy, as that time.

Others may offer different solutions...

Frederic


On 03/02/2021 15:14, Bastian Hirn-Derksen wrote:
> To whom it may concern,
> 
>  
> 
> Im working with GNU McSIM to create PBPK models. Now I have the question
> if its possible to use a parameter calculated in dynamics or CalcOutputs
> at a certain time point as a fixed value, just like in this equation: x
> = y(t0) – y(t).  That would mean that the model uses the value from y
> calculated at time 0 as a fixed value in this equation and then subtract
> the values of y calculated at different timepoints t. When this is
> possible it would help me a lot.
> 
>  
> 
> Thank you for your help.
> 
>  
> 
> Kind regards,
> 
>  
> 
> --
> 
> Bastian Hirn-Derksen
> 
> Apotheker
> 
> Westfälische Wilhelms-Universität Münster Institut für Pharmazeutische
> und Medizinische Chemie
> 
> - Klinische Pharmazie -
> 
> Raum A 120.202
> 
> Corrensstraße 48
> 
> 48149 Münster, Germany
> 
> Phone: +49 251 83 33364
> 
> Fax.: +49 251 83 32144
> 
> E-mail: b_hirn01@uni-muenster.de <mailto:b_hirn01@uni-muenster.de>
> 
>  
>