Re: [deal.II] Getting zero determinant for the stokes problem

fgang Bangerth wrote: > > > On 10/30/24 08:25, Abbas Ballout wrote: > > > > Yeah I was aiming to compute the smallest eigenvalue. > > I guess my tittle was off. I was just trying to aim to the fact that the > > stiffness matrix > > I wrote to an output file and t

Re: [deal.II] Getting zero determinant for the stokes problem

since my changes were minimal to the step example. I'll double check what I did later too. best, Abbas On Monday, October 28, 2024 at 10:57:05 PM UTC+1 Wolfgang Bangerth wrote: > > On 10/28/24 15:26, Abbas Ballout wrote: > > > > I wanted to look at the determ

Re: [deal.II] Finite Volume Method - Matrix/RHS assembly

Nick, 2) When you use DG0, all of the terms in the weak from cancel to zero except for the face term penallty*jump(u)*jump(v). (du/dx and dv/dy are zero inside an element) That penalty term in the DG community is seen as something that adds stability and isn't at the core of the scheme. In

[deal.II] Re: Finite Volume Method - Matrix/RHS assembly

Nick, You can look at step 74. It has EXACTLY what you need. On Wednesday, June 19, 2024 at 10:33:18 PM UTC+2 nikl...@stanford.edu wrote: > Dear all, > > I'm new to deal.ii and I would like to use it to gradually build a > simulator for charge/mass transport inside batteries. > > Since the eq

Re: [deal.II] Project cell quadrature point data to boundary

Almonaci, I think you'll need the compute_projection_from_face_quadrature_points_matrix tfunction. Here's how you might use it: std::vector distributed_field; distributed_field.reinit(dof_handler.locally_owned_dofs(), mpi_communicator); FullMatrix qpoint_to_dof_matrix(fe.dofs_per_face, face_

Re: [deal.II] Shape gradients of (f(x)*\phi_i)

nuary 23, 2024 at 10:24:55 PM UTC+1 Wolfgang Bangerth wrote: > On 1/23/24 13:09, Abbas Ballout wrote: > > > > Sorry I meant to say I don't want to use that chain rule. > > You mean the product rule? Either way, why is it that you don't want to > use >

Re: [deal.II] Shape gradients of (f(x)*\phi_i)

: > Abbas, > > \dfrac{\partial f(x) \phi_i}{\partial x} is just \dfrac{\partial > f(x)}{\partial x} \phi_i+f(x)\dfrac{f(x)}{\partial x} which I would use. > There is no need to integrate by parts. > > Best, > Daniel > > On Tue, Jan 23, 2024 at 2:37 PM Abbas Ballout >

[deal.II] Shape gradients of (f(x)*\phi_i)

I know I can query the standard shape gradient at a quadrature point with fe_values.shape_grad(i, q). Is it possible to query for something like the gradient of the shape function multiplied by another function? I need \dfrac{\partial f(x) \phi_i}{\partial x} but I don't want to integrate by p

Re: [deal.II] Liltle help with MUMPS

023 at 11:39:59 a.m. UTC-5 Wolfgang Bangerth > wrote: > >> >> >> On 11/15/23 04:09, Abbas Ballout wrote: >> > >> > If I run mpirun -np2 the assemble times are 25.8 seconds and the MUMPS >> > solve times are 51.7 seconds. >> > If I run m

Re: [deal.II] In example 40, the results are significantly different between the first-order and second-order finite element meshes

ztdep, You got me curious You can output the results of the Kelly error estimate with something like this in the data output: *Vector estimated_error_per_cell(triangulation.n_active_cells()); KellyErrorEstimator::estimate(dof_handler,QGauss(fe.degree + 1),

[deal.II] Liltle help with MUMPS

This isn't a dealii problem per-se. I am trying to run a number of simulations with different parameters of the same code with the underlying solver being MUMPS. I am using *mpirun --cpu-set * to bind and isolate the different simulations to different cores (As I believe I should) *Profilin

[deal.II] Re: Difference between 2 Wasy to Initialize System Matrix in MPI World

Did you try to run in Debug? If not give it a try and see if an exception is thrown. Abbas On Thursday, September 28, 2023 at 3:15:14 AM UTC+2 hitl...@gmail.com wrote: > Hello all, > > > Previously, I initialized my system matrix in this way (option A) > > DoFTools::make_flux_sparsity_pattern

Re: [deal.II] Neumann Boundary condition in MeshWorker for Automatic Differentiation

Jost, For looping on the boundaries, you'll have to write an extra lambda amd pass that to the MeshWorker. You can look at step 12 or 74 for this. Also following this cause I want to know what are the MeshWorker alternatives since I am relying heavily on it in my code Best, Abbas On Thursd

[deal.II] Re: How to use cell stiffness matrix to build global stiffness matrix

Not really experienced with eigen so I am not exactly sure. Abbas On Tuesday, August 1, 2023 at 6:53:35 PM UTC+2 dim...@gmail.com wrote: > Hello Abbas, > > Thanks for your reply. > > I will take a look at the step13. > > Howerver, I would like to know if the cell matrix transform seems like the

Re: [deal.II] Q: Question about extracting part of a vector

Thank you for your response. I have actually written something, but I need > to test it. It would be great to have a look at your work as well, so we > can compare. > > Best regards, > Najwa > > On Mon, 31 Jul 2023 at 10:48 PM Abbas Ballout > wrote: > >> Najwaa

[deal.II] Re: How to use cell stiffness matrix to build global stiffness matrix

Lance, I am not sure if I understood you correctly. Maybe looking at the local_assemble_matrix() function in step:13 might help. Abbas On Tuesday, August 1, 2023 at 11:00:10 AM UTC+2 dim...@gmail.com wrote: > Hello dear group, > > I have one question which is about how to build global stiff

Re: [deal.II] Q: Question about extracting part of a vector

Najwaa, I submitted a pull request recently about something similar . (I guess) Maybe that would help. Abbas On Monday, July 31, 2023 at 7:37:59 PM UTC+2 najwaa...@gmail.com wrote: > Dear Wolf

Re: [deal.II] Integrate difference isn't picking on the

s are compiled and you're just on the linking > stage you don't really run into this. > > Alternatively, I think that some other folks use gold linker or the lld > linker (in case you can't get mold to work). > > - Lucas > > > On Sat, Jul 22, 2023, 11:37

Re: [deal.II] Integrate difference isn't picking on the

If I change a single line in deal I'll have to wait a good amount of time for it to compile. Do you all go through this? All I have is a 4 cores and 16 GBs of RAM on my Laptop. On Monday, July 17, 2023 at 9:48:00 AM UTC+2 Abbas Ballout wrote: > YES. Would take me a while but I

Re: [deal.II] How to set refinement flag on the neighbouring cell when it is owned by another processor?

I ended up passing the assemble_own_interior_faces_both flag to mesh-worker mesh loop. I will probably have to use these Consensus algorithms sooner or later anyway. Thank you. Abbas On Thursday, July 13, 2023 at 3:17:59 AM UTC+2 Wolfgang Bangerth wrote: > On 7/11/23 08:23, Abbas Ball

Re: [deal.II] Integrate difference isn't picking on the

YES. Would take me a while but I ll do it. Be prepared for many questions. On Monday, July 17, 2023 at 2:44:01 AM UTC+2 Wolfgang Bangerth wrote: > On 7/16/23 07:22, Abbas Ballout wrote: > > I get this error when I call the > exact_solution_vector_function.gradient(p1): > &

Re: [deal.II] Integrate difference isn't picking on the

tion that isdeclared as a virtual function in a base class but that has not beenoverridden in your derived class.* Calling value works fine but not gradient even though I have overridden both functions. On Friday, July 14, 2023 at 8:55:34 PM UTC+2 Wolfgang Bangerth wrote: > On 7/14/23 09:34,

[deal.II] Integrate difference isn't picking on the

I am overriding the value and the gradient member functions in the TensorFunction class then similar to step 7 I am using compute_global_error to compute the L2: and H1 norms. I have to convert my TensorFunction to a vector valued function in order to do this using VectorFunctionFromTensorFunct

Re: [deal.II] Deformation gradient at face quadrature point for current traction

Krish, I could do this following step 18 and how history variables are constructed there. It was straightforward in case you are interested. On Wednesday, June 28, 2023 at 7:55:19 PM UTC+2 Wolfgang Bangerth wrote: > On 6/26/23 00:49, Krish wrote: > > > > I am following step-44 to solve an

Re: [deal.II] Is it normal for the results to vary this much when running in parallel.?

6/24/23 09:13, Abbas Ballout wrote: > > ** > > > > Bellow I have plotted the rhs before and after applying boundary > constraints > > when running with 1, 2 and 3 cores. > > The rhs looks different at the boundary with MPI 3 as opposed to MPIs 1 > and 2

Re: [deal.II] Is it normal for the results to vary this much when running in parallel.?

s is doing something special to ghost nodes? Best, Abbas On Friday, June 16, 2023 at 11:44:43 PM UTC+2 Wolfgang Bangerth wrote: > On 6/12/23 02:57, Abbas Ballout wrote: > > ** > > > > I am running step 18. > > > > This is the output I getting

[deal.II] Re: Is it normal for the results to vary this much when running in parallel.?

10:57:03 AM UTC+2 Abbas Ballout wrote: > I am running step 18. > > This is the output I getting for a single quasi-tatic step with mpirun 1 : > > > > > > > > > > > > > > * Cycle 0:Number of active cells: 3712 (by partition: 3712) &g

[deal.II] Is it normal for the results to vary this much when running in parallel.?

I am running step 18. This is the output I getting for a single quasi-tatic step with mpirun 1 : * Cycle 0:Number of active cells: 3712 (by partition: 3712) Number of degrees of freedom: 17226 (by partition: 17226)Assembling system... norm of rhs is 1.88062e+10

Re: [deal.II] Re: How can I visit a face exactly once when running with MPI?

Thanks Wolfgang, Time, and Bruno for your comments. I hate to say thanks too much so sometimes I don't. On Wednesday, June 7, 2023 at 4:40:51 PM UTC+2 Wolfgang Bangerth wrote: > On 6/7/23 01:21, Abbas Ballout wrote: > > I set the flag when I create the mesh, then I loop on the

Re: [deal.II] Re: How can I visit a face exactly once when running with MPI?

aution when opening links or attachments if you do not recognize > the sender. > > > > ZjQcmQRYFpfptBannerEnd > > Right, it won't clear it everywhere. You would need to use MPI to clear > the flag on the other processor. If you would do that you would create a > huge amount of messages

[deal.II] Re: Is it possible to output data in vtk at quadrature points for me to view in something like Paraview?

I figured this one out. I just wrote the output at quadrature points to a text file that I read that in Paraview. On Wednesday, May 31, 2023 at 5:08:38 PM UTC+2 Abbas Ballout wrote: > This one is quick: > I want to visualise my data at q_points. > > I know that paraview will int

[deal.II] Is it possible to output data in vtk at quadrature points for me to view in something like Paraview?

This one is quick: I want to visualise my data at q_points. I know that paraview will interpolate the data but still. -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message

Re: [deal.II] How are both the gradient components calculated in deal?

Thanks for the reply. I was under the impression that get_function_gradients calculates the gradient based on the \sum_j U_j that are on the face. On Monday, May 22, 2023 at 7:42:34 PM UTC+2 Wolfgang Bangerth wrote: > On 5/22/23 06:21, Abbas Ballout wrote: > >

[deal.II] How are both the gradient components calculated in deal?

Excuse this basic question but how is the gradient at a quadrature point on a face calculated in deal? Take this code snipped for example: QGauss<1> face_quadrature_formula(fe.degree + 1); FEFaceValues<2> fe_face_values(fe, face_quadrature_formula, update_values | update_quadrature_points | upd

Re: [deal.II] Simple Query about an example in the code gallary

Sorry I deleted this before it had any comments on it. I thought it would disappear. Won't happen again. Abbas On Wednesday, April 26, 2023 at 7:18:59 PM UTC+2 Wolfgang Bangerth wrote: > On 4/26/23 03:34, Abbas wrote: > > Why is it that in step 40 the locally relevant solution is initialised

[deal.II] Re: How can I visit a face exactly once when running with MPI?

This works!! Thanks. I am guessing something like: if(cell_neighbour->is_ghost()==true) cell->face(neighbour_face_number)->clear_user_flag(); won't clear the user flag everywhere either, because that didn't work. Right? On Thursday, April 27, 2023 at 2:48:23 PM UTC+2 bruno.t...@gmail.com wr

Re: [deal.II] How can I integrate along a surface/edge within the domain? Can I tag the surface/edge with an ID?

Thank you.This works. For anyone seeing this in the future, change "int face" to "int f" in the for loop. -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are

[deal.II] Preconditioner for the time harmonic Maxwell equation

This isn't a dealii problem and I am sorry if this isn't the right place to post to, but if there is someone who could give me some hints on how I would approach this then it would be you guys. I have been trying to solve the time harmonic maxwell equation discritized with the use of Nedelec e

Re: [deal.II] using VectorTools::project_boundary_values_curl_conforming_l2 with FEsystem fe(FE_Nedelec<3>(0), 2)

partof the system my output for the constraint is: 1. 1 = 0 2. 3 = 0 3. 5 = 0 4. 7 = 0 On Monday, May 3, 2021 at 8:22:58 PM UTC-4 Wolfgang Bangerth wrote: > On 5/3/21 7:43 AM, Abbas Ballout wrote: > > *The right hand side of the second equation isn't

[deal.II] using VectorTools::project_boundary_values_curl_conforming_l2 with FEsystem fe(FE_Nedelec<3>(0), 2)

Some context: I am trying to model a waveguide which would require me to solve the double curl equation curlxcurlxE-cE=0 where c is some constant(real or imaginary) subject to nxE=nxf on different parts of the boundary where f can be real or imaginary also. The problem requires the use of Ned