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3
votes
1answer
64 views

Signed cell adjacency matrices (boundary operators)

In How to obtain the cell-adjacency graph of a mesh? there are some great answers that show how to obtain the cell adjacency matrix of a mesh. How would one generalize these to incorporate the ...
5
votes
2answers
135 views

Adjacent faces in a discrete mesh

I have a MeshRegion R and I want to extract all pairs of adjacent faces efficiently. The way that I've been computing this is demonstrated below: ...
9
votes
2answers
349 views

Picking mesh elements that are not on the border of the mesh

As an example, let's say I use a set of random points to create a Voronoi mesh pts = RandomReal[{-1, 1}, {100, 2}]; VoronoiMesh[pts, {-1, 1}] and get something ...
50
votes
2answers
1k views

A geometric multigrid solver for Mathematica?

Cross posted to community.wolfram.com Mathematica ships a variety of linear solvers through the interface LinearSolve[A, b, Method -> method] the most ...
3
votes
2answers
132 views

Add interpolating functions over an unstructured mesh to get a single interpolating function

In a Newton iterative FEM PDE solver I am writing, each iterative step involves updating the current solution function u by adding to it the increment function <...
18
votes
5answers
1k views

How to obtain the cell-adjacency graph of a mesh?

In addition to the accepted answer, see also the answer by Chip Hurst. This functionality is built in, but not documented. Given an arbitrary mesh region, how can I efficiently obtain the graph ...
2
votes
0answers
55 views

Correspondence between points and cell of their VoronoiMesh [duplicate]

It is not unreasonable to expect that the $k^\text{th}$ cell of a VoronoiMesh belongs to the $k^\text{th}$ point passed to it. However, this is not the case: <...
13
votes
3answers
593 views

Improve the mesh smoothing procedure

My question is inspired by this answer about meshing with quadrilateral elements. The following functions are my (naive) try of implementing the Laplacian smoothing. I find interior nodes in the mesh ...
2
votes
1answer
173 views

Manipulate gets stuck when ConvexHullMesh is made transparent

Version 10.3 The followinng Manipulate is a bit slow, but quite OK ...
1
vote
1answer
683 views

Improving NDSolve computation speed for 3D stationary PDE

Continuing my last question, I am trying to solve 3D Schrodinger equation (with mass equals to 1) and with no potential (I will add a potential later). The analytical solution for this equation is ...