Re: [Getfem-users] High level generic assembly procedures

[Marco Pischedda]

Ok thank you,

I tried it and it works. I will let you know if there are other problems.

Thanks

Marco

2014-04-01 17:16 GMT+02:00 Yves Renard <address@hidden>:
>
> Dear Marco,
>
> All seems to me correct in your implementation. This is probably just
> the test line 2074 of getfem_generic_assembly.cc
> which is not correct for one-dimensionnal problems.
>
> I think the test should be
>
>  GA_DEBUG_ASSERT((qdim == 1 && t.sizes()[0] == N) ||
>                       (t.sizes()[1] == N && t.sizes()[0] == qdim) ||
>                       (N == 1 && t.sizes()[0] == qdim),
>                       "dimensions mismatch");
>
> May be you can try this. I will validate it if it works.
>
> Regards,
>
> Yves.
>
>
>
> Le 01/04/2014 16:56, Marco Pischedda a écrit :
>> Dear Yves,
>>
>> thank you for your fast answer.
>>
>> I have another question:
>>
>> - I have a monodimensional problem but the unknowns are vectorial. I
>> set the vectorial
>> dimension of the unknows with mf_u.set_qdim(3) and with mf_p.set_qdim(3).
>> When I define the expression " Grad_u.Test_p "  i receive the following 
>> error:
>>
>> terminate called after throwing an instance of 'gmm::gmm_error'
>>   what():  Error in
>> ../../getfem-svn/getfem/src/getfem_generic_assembly.cc, line 2074 :
>> dimensions mismatch
>>
>> Grad_u should be a 2nd order tensor, while Test_p should be a vector.
>> I suppose the
>> problem is that Grad_u is interpreted as a vector while Test_p is
>> interpreted as a scalar.
>> How can I use the high level generic assembly procedures on vectorial 
>> problems
>> defined on a monodimensional computational domain?
>>
>> Thanks in advance
>>
>> Marco
>>
>>
>>
>>
>>
>> 2014-04-01 8:42 GMT+02:00 Yves Renard <address@hidden>:
>>> Dear Marco,
>>>
>>> Yes, your code is correct and it should work correctly.
>>> Note that you can also use the high level generic assembly with the
>>> model object using a generic assembly brick.
>>> Note also that high level assembly is only available in the svn
>>> repository version of Getfem
>>> (and a very recent version, at least r4570 because a bug have been
>>> corrected on coupled problems recently).
>>>
>>> Yves.
>>>
>>>
>>> Le 31/03/2014 14:00, Marco Pischedda a écrit :
>>>> Dear all,
>>>>
>>>> I want to use the high level generic assembly procedures in order to
>>>> use the automatic differentation for calculating the Jacobian of a
>>>> non-linear problem.
>>>>
>>>> For example I want to calculate the Jacobian of two vectorial
>>>> equations in the unknowns "u" and "p". The first vectorial equation is
>>>> (u+p).Test_u while the second is (u+p).Test_p.
>>>>
>>>>  It is correct the following code?
>>>>
>>>>  gmm::sub_interval Iu(0, ndofs_u);
>>>>  gmm::sub_interval Ip(ndofs_u,ndofs_p);
>>>>  workspace.add_fem_variable("u", mf_u, Iu, U);
>>>>  workspace.add_fem_variable("p", mf_p, Ip, P);
>>>>  workspace.add_expression("(u+p).Test_u + (u+p).Test_p",mim);
>>>>  getfem::model_real_sparse_matrix Jac(ndofs_u+ndofs_p, ndofs_u+ndofs_p);
>>>>  workspace.set_assembled_matrix(Jac);
>>>>  workspace.assembly(2);
>>>>
>>>> In the matrix Jac I have the Jacobian of the system?
>>>>
>>>>
>>>> Thanks in advance
>>>>
>>>> Marco
>>>>
>>>> _______________________________________________
>>>> Getfem-users mailing list
>>>> address@hidden
>>>> https://mail.gna.org/listinfo/getfem-users
>>>
>>> --
>>>
>>>   Yves Renard (address@hidden)       tel : (33) 04.72.43.87.08
>>>   Pole de Mathematiques, INSA-Lyon             fax : (33) 04.72.43.85.29
>>>   20, rue Albert Einstein
>>>   69621 Villeurbanne Cedex, FRANCE
>>>   http://math.univ-lyon1.fr/~renard
>>>
>>> ---------
>>>
>
>
> --
>
>   Yves Renard (address@hidden)       tel : (33) 04.72.43.87.08
>   Pole de Mathematiques, INSA-Lyon             fax : (33) 04.72.43.85.29
>   20, rue Albert Einstein
>   69621 Villeurbanne Cedex, FRANCE
>   http://math.univ-lyon1.fr/~renard
>
> ---------
>