[deal.II] Re: cout stiffness matrix in step-3

Dear Michael, There are a number of "print" functions in the sparse matrix classes. See the answer to this question , as well as some of the surrounding discussion for more details. Kin

[deal.II] cout stiffness matrix in step-3

Hello! I'm trying to cout the stiffness matrix $A_{ij}$ in step-3 for a reasonably small domain 2d mesh..is $A_ij$ a function in the FEValues class..? Just trying to learn the basics of dealii.. Thanks in advance, Michael -- The deal.II project is located at http://www.dealii.org/ For mailing

Re: [deal.II] Re: How to shift a ConstraintMatrix that initialized with IndexSet?

Dear Daniel, It works now. I made a mistake before. Thank you for your help. Best, Ce Qin 2017-01-02 23:35 GMT+08:00 Daniel Arndt : > Ce Qin, > > Removing the assertion works, but it will cause a problem. Since the >> ConstraintMatrix internally uses local_lines to determine the position >> of

[deal.II] Re: Periodic Boundary Condition

Dear Daniel, Happy new year. I wish a wonderful new year for you ! This is only (directly) possible if you are not using inhomogeneous > constraints. In that case, you can call > ConstraintMatrix::distribute_local_to_global separately for matrix and > right-hand side. > I am struggling to ap

[deal.II] p::d::SolutionTransfer::interpolate fails with LA::distributed::Vector's in the specific case

Hi all, I came across a very weird problem today. When using p::d::SolutionTransfer during refinement I get the following error during interpolate step at the second refinement cycle: 61: An error occurred in line <686> of file in function 61: void dealii::LinearAlgebra::distributed::Vecto

Re: [deal.II] Re: How to shift a ConstraintMatrix that initialized with IndexSet?

Ce Qin, Removing the assertion works, but it will cause a problem. Since the > ConstraintMatrix internally uses local_lines to determine the position of > a ConstraintLine, we can not insert new line or query an existing line > anymore. > The attached examples works for me as far as I can tell.

[deal.II] Re: compute sign of the determinant of the global tangent stiffness matrix

Hi Denis. I also don't know how the first method can be implemented. I read the above models in the book By Neto, Peric and Owen “Computational method for plasticity”. They have been computed the determinant of the stiffness matrix during solving the linear system using the classical frontal m

[deal.II] Re: compute sign of the determinant of the global tangent stiffness matrix

Hi Pasha, It looks like what you need is to know whether the matrix is positive-definite or negative-definite. I don't think there is way to calculate a determinant of an arbitrary huge sparse matrix such as Epetra_CrsMatrix, that is wrapped in TrilinosWrappers. I gave a quick look at Epetra_Crs