[Getfem-users] Transient analysis-dirichlet conditions

[Sébastien Janas]

Hi all,

I want to solve the transient linear equation of diffusion.

It seems that there is no function pre-build in getfem for the  
transient problems. So I assemble the mass matrix (MM) and stiffness  
matrix (SM) "manually", and then construct the linear system A*X=B  
using the backward euler

A = (MM + delta t * SM)
B = MM * X(t-1)

Then I have to impose dirichlet conditions on the surface. I import my  
mesh from gmsh, where the surface are tagged with a number (in my case  
200). How can I modify my linear system to take into accompt the  
dirichlet conditions? All the functions I found in the documentation  
are in the case where you use model bricks or standard assembly  
procedures...

If I can have the list of node numbers tagged by 200 I would use the  
penalty method. But I am not able to obtain these list.

I am using the python interface of getfem.

Thanks for your help,

Best regards,

Janas Sébastien