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[Getfem-users] Problem using GradGT in assembling boundary condition
From: |
Cédric Venet |
Subject: |
[Getfem-users] Problem using GradGT in assembling boundary condition |
Date: |
Mon, 19 Jul 2010 10:30:30 +0200 |
User-agent: |
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.4) Gecko/20100608 Lightning/1.0b2 Thunderbird/3.1 |
Hi,
The usage of GradGT is not documented and it is never used. From the
documentation, GradGT should be the representation of K the gradient of
the geometric transform. I suppose that it takes two "arguments". First
the line number (ie the dimension in the problem/real/mesh space) and
then the column number (ie the dimension in the reference space).
I would like to assemble the condition (on the boundary of a 2D mesh so
on 1D element):
integral of ( du/dt * v )
with t the tangent vector. I tried numerous formulation around this one:
"M(#1,#1)+=sym(comp(Grad(#1).GradGT().Base(#1))(:,i,i,k,:))"
but none seems to work. for me, i should be summed on {0,1} and k on {0}
thus giving the formula:
integral of ( (du/dx*dx/dt + du/dy*dy/dt) * v )
the error is in getfem_mat_elem.cc line 364. (in the function
expand_product_daxpy)
it seems that the vector t is too small and the code try to dereference
the iterator pt after the end of t.
I tried to understand how t was sized, wihtout much success. I see that
adjust_sizes is called numerous times. the last call before the crash is
with the "array" [4 2 2 2 1] in argument. (my mesh use quad).
Can you help me?
Regards,
Cédric
- [Getfem-users] Problem using GradGT in assembling boundary condition,
Cédric Venet <=