[Getdp] Characteristic function in galerkin term

Ruth V. Sabariego r.sabariego at ulg.ac.be
Fri Jun 19 09:41:39 CEST 2009


You should use X[] and Y[] instead of $X and $Y.
Regards,
Ruth


sdurand wrote:
> Hello everybody,
>
> is it possible to use a characteristic function of the form
>
> Iee [domainTot] = ($X^2 + $Y^2 <1 ) ? 1 : 0;
>
> in the Galerkin term to integrate over an inner domain? I want to use
> something like
>
> Galerkin { [ Iee[]*({u}-{ud}), {p} ]; In domainTot;
> 	Jacobian Vol; Integration GradGrad; }
>
> where domainTot is the whole domain and the integral should be
> calculated over the unit circle.
>
> I always get the "Null right hand side of linear system"-remark.
> However, if I plot the function Iee[]*( u - ud ) in gmsh after
> postprocessing, it is indeed zero outside, but it is certainly not zero
> inside the unit circle. How can I solve this problem?
>
> Thank you,
> Stephane
>
>
>   


-- 
Dr. Ir. Ruth V. Sabariego
University of Liege, Institut Montefiore,
Dept. of Electrical Engineering & Computer Science, 
Applied & Computational Electromagnetics (ACE),
Sart Tilman Campus, Grande Traverse, 10 (B28), B-4000 LIEGE, Belgium
phone: +32-4-3663737 -- fax: +32-4-3662910 -- http://elap.montefiore.ulg.ac.be/