Timeline for Finding eigenvalues for Laplacian operator for 3D shape with Neumann boundary conditions
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
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| Jul 19, 2016 at 14:43 | comment | added | Michael E2 | @Alex There's some discussion about how NeumannValue[val, pred] works here and a little more here. The way FEM works seems to add val to the components of the appropriate system matrices corresponding to boundary elements for which pred is true. (M certainly computes the boundary elements when discretizing a region; try emesh["BoundaryElements"] for any ElementMesh.) | |
| Jul 19, 2016 at 11:53 | comment | added | Alex | Yes, Gamma is supposed to be the boundary of the pyramid. I was just surprised that Mathematica can calculate the derivative on a surface without explicitly given surface. | |
| Jul 19, 2016 at 3:48 | comment | added | Michael E2 | @Alex Isn't Gamma the boundary of the pyramid? If not, could you describe what it is? (The True in NeumannValue[..., True] defines the condition to apply to the whole boundary of the pyramid.) | |
| Jul 19, 2016 at 2:17 | comment | added | Alex | Thank you Michael, your remark on how to specify correctly Neumann boundary conditions is very helpful. Fortunately, in my case the condition is homogeneous. It did work for my Mathematica 10.3 as well. Are you sure that NeumannValue(0, True) is the same thing as NeumannValue[0, Element[{x, y, z}, Γ]] ? | |
| Jul 19, 2016 at 0:54 | history | answered | Michael E2 | CC BY-SA 3.0 |