[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Getfem-users] Problems to build a matrix for a boundary term

From: Ronan Perrussel
Subject: Re: [Getfem-users] Problems to build a matrix for a boundary term
Date: Sat, 05 Sep 2009 14:21:04 +0200
User-agent: Thunderbird (X11/20090817)

Dear Iago,

the exact integration is mainly linked to the use of an affine mesh.
Is it the case here? You speak about a circular hole and maybe you use second order transformation for the elements around the hole...

I hope it helps.

Best regards,

Iago Barbeiro a écrit :
Dear Getfem++ users,

I am facing problems to build an elementary matrix using the generic assembly procedure and I hope anyone could give me a hand.

It is a boundary integral in a two dimensional mesh (It is a circular domain with a circular hole inside and I want to integrate over both boundaries):


So it is a bilinear form in "p" and "dp" where both are scalars defined with the same fem (mf_p).

For that I have tried the following block:

*template<typename MAT> *
*void asm_P_Lap_boundary(const MAT &K_,*
* **                   const mesh_im &mim,*
* **                   const mesh_fem &mf_p, *
* **                   const mesh_region &rg) {*
*     MAT &K = const_cast<MAT &>(K_);*
*     getfem::generic_assembly assem;*
*   *
*     assem.set("M(#1,#1)+=comp(Grad(#1).Normal().Base(#1))(:,i,i,:);");*
*          *
*     assem.push_mi(mim);*
*     assem.push_mf(mf_p);*
*     assem.push_mat(K);*
*     assem.assembly(rg);*
* }*

Where the mesh_region was built using:

*getfem::mesh_region boundary;*
*getfem::outer_faces_of_mesh(mymesh, boundary);*

But then I found an error message, which is:

*|      An error has been detected !!!      |*
*Error in, line 121 : *
*Exact integration not allowed in this context*

Why exact integration would not be allowed here? Am I doing something wrong? Any light?

Thanks for your attention!

Iago C. Barbeiro

Getfem-users mailing list

Attachment: ronan_perrussel.vcf
Description: Vcard

reply via email to

[Prev in Thread] Current Thread [Next in Thread]