Questions tagged [mesh]
Questions on the use and creation of meshes including the use of MeshRegion, ElementMesh, and TetGenLink.
538
questions
3
votes
1answer
95 views
Mass Transport FEM Using Quad Mesh
This question is a follow-up to my previous question and an attempt to implement @Tim Laska's excellent approach of setting up an anisotropic quad mesh. I'm solving a similar problem to @Tim Laska's ...
1
vote
0answers
79 views
Why is there no heat being transfered in my program?
I have been working on this code and am new to this coding language. I have been trying to model the transfer of heat through a hot plastic being cooled in a water bath. For some reason I have not ...
5
votes
2answers
167 views
How to fill in interior in a mesh region
Say I have a mesh region which encloses a region. How do I get a mesh region where this region is filled? Take for example the meshregion below:
...
1
vote
0answers
40 views
obtain the analytics region from mesh or vtk file
Is it possible to obtain the region inequalities from a mesh file (vtk-file).
On gmsh I build a Sphere, and with Mathematica I would like to obtain the analytics region function, that's is possible?.
...
2
votes
1answer
81 views
ToElementMesh Error/General meshing strategies
I am trying to create a mesh using ToBoundaryMesh as opposed to DiscretizeRegion. I was hoping this would be a better strategy ...
5
votes
1answer
153 views
Improving mesh and NDSolve solution convergence
I have developed the code below to solve two PDEs; first mu[x,y] is solved for, then the results of mu are used to solve for phi[x,y]. The code works and converges on a solution as is, however, I ...
5
votes
2answers
228 views
Mesh Generation help
I am having trouble generating a mesh of a rectangle inside another rectangle. I have been following the steps on this article: https://reference.wolfram.com/language/PDEModels/tutorial/HeatTransfer/...
5
votes
3answers
251 views
How to discretize a parametric polar surface ensuring the correct periodicity of the mesh
I am trying to discretize a polar surface using a combination of ParametricPlot3D and DiscretizeGraphics. Unfortunately, the ...
1
vote
0answers
46 views
Why does ConvexHullMesh give inconsistent output stuctures?
I know much of the stuff in ConvexHullMesh needs some TLC convexhullmesh-inconsistency
But, can anyone see why this would produce inconsistent output:
Case 1 (expected behavior):
...
5
votes
1answer
92 views
ConvexHullMesh inconsistency
I am seeing an inconsistency in ConvexHullMesh that I don't understand.
Here is
Rhull = ConvexHullMesh[pts8]
where the $8$ ...
2
votes
2answers
50 views
How to discretize the boundary of two regions?
Problem
How to discretize a surface constructed with multiple components?
Unsuccessful attempts include combining the objects top and ...
4
votes
1answer
69 views
9
votes
1answer
290 views
Help to create a 2D mesh generator (FEM)
I'm working in a finite element mesh generator. I built this function which generates an 8 node mesh (polynomials of order 2) without any interior node:
...
1
vote
1answer
39 views
How can I specify the output mesh resolution for ListPlot3D?
I am using a grayscale image to generate a 3D topology, with the help of ListPlot3D. However, the output mesh resolution is far too high for my purposes. I need to ...
1
vote
1answer
36 views
Unable to affect mesh regions with DiscretizeGraphics
Problem
On the sphere, it is easy to control the resolution of the mesh in DiscretizeGraphics using the MaxCellMeasure ...
4
votes
1answer
44 views
VoronoiMesh with boundary edges removed
I would like to create a Voronoi diagram without the boundary edges highlighted.
This code
gVD = VoronoiMesh[X, MeshCellStyle -> {{1, All} -> {Thick, Red}}]
...
4
votes
1answer
106 views
Drawing a “realistic” VoronoiMesh
Consider a set of points generated via Lloyd's relaxation algorithm
...
1
vote
0answers
27 views
Extract data from ConvexHullMesh [closed]
I have a ConvexHullMesh and want to extract the bounding points.
I am familiar with using Cases to extract data from plots but ...
0
votes
0answers
44 views
Why BoundingRegion Fails in such cases
When I was playing this answer of tube, function TubePolygons used in my question.
...
0
votes
1answer
62 views
Mesh Refinement for interpolation of f[x,y] fails for all but the simplest f
I would like to interpolate a function, f[x,y,z], on a mesh of the unit cube, starting with a coarse tetrahedral mesh and refining tetrahedra as needed to reduce the interpolation error below a ...
2
votes
1answer
99 views
Finding lower boundary of a 3D object in list format
I have the following point list and would like to find the points located in the lower boundary of the 3D object (It is part of a body torso).
https://pastebin.com/L12n0Gfr
I am using the following ...
3
votes
0answers
49 views
Unfold/develop a RevolutionPlot3D mesh onto a 2D plane?
I'm making my own blimp out of emergency blankets (Mylar), and I want it to have a NACA0025 airfoil shape. I'm new to Mathematica, but I still managed to create the shape I wanted with ...
14
votes
3answers
212 views
Ordering Problem With VoronoiMesh
Imagine I want to model 2D cells moving in a tissue. Consider, as an example, Lloyd's relaxation algorithm. Using VoronoiMesh I'm able to mimic some cell movement. ...
4
votes
1answer
83 views
Capturing mesh information
Mesh information
Using the helpful tips from Triangular mesh of random points on a sphere, it's easy to generate solids:
...
14
votes
2answers
456 views
How to make a structured mesh with a hole and extrude it
I am trying to use the FEMAddOns package to make a structured mesh with a hole and then extrude it. As a warm up example this worked nicely.
...
4
votes
1answer
127 views
MeshRefinementFunction analogue for ToElementMesh
MeshRefinementFunction according to the documentation is an option for DiscretizeRegion. Is there an analogue for ...
5
votes
1answer
52 views
How to create a 1D mesh from a curved line (with ToElementMesh)
I want to create an element mesh from an arc $x=Rcos(\varphi), y=Rsin(\varphi)$, with $R=100, \varphi \in [0,\pi/4]$ which looks like this:
...
6
votes
2answers
207 views
Computing volume of intersection of two regions
I am trying to compute the volume of intersection of the following two regions:
...
7
votes
1answer
181 views
Convert ConvexHull to Inequality
I have the following convex hull.
P0={0,0,0};
P1={1,0,0};
P2={0,1,0};
P3={0,0,1};
ConvexHullMesh[{P0,P1,P2,P3}]
Now I want the region algebraically as equality ...
0
votes
0answers
62 views
Surface area of a list of points
I would like to know how I can get the area of the following point list. I am using the following script to make a mesh region and then find the area. However, the area is much larger than the value ...
0
votes
1answer
57 views
RegionResize works improperly with different digital accuracy
The data is copied from the output cell of my original data.
...
9
votes
3answers
510 views
How to determine if a point is within a concave 3D polyhedron?
Generally, if you have a 3D polyhedron and wanted to check if a point was within it, you would use something like a ConvexHullMesh to create a region, which you can ...
1
vote
1answer
60 views
How to efficiently animate changing mesh on a fixed 3D plot?
Say I'd like to visualise a height function of a torus by animating a plane going upwards, and highlighting the intersection via Mesh/...
9
votes
1answer
128 views
Why do some PlotThemes not work with Mesh as expected? What can be done about it?
While updating my answer for (189038) I noted that some PlotThemes do not work with Mesh in a meaningful way:
...
4
votes
1answer
104 views
How to draw surface with four space curves as boundaries
How to draw a surface with four space curves as boundaries of the surface?
...
4
votes
1answer
95 views
MeshTools package: can one translate 3d meshes in order to then merge them?
I have created a 3d region for Laplace's eqn
...
11
votes
4answers
589 views
Area/Volume of a 2D/3D object as it is filled up with water
How could I get the volume of water on a region as it is filled up with water from below? Assume gravity points in some appropriate downward axis like -y (or -z in 3D) so the water fills upward from ...
6
votes
1answer
106 views
RandomPoint inside mesh for walk-on-spheres Monte Carlo PDE solver
I'm trying to understand a Monte-Carlo Laplace/Poisson PDE solver:
http://www.cs.cmu.edu/~kmcrane/Projects/MonteCarloGeometryProcessing/paper.pdf
This method inspired by random-walks and ray-tracing ...
3
votes
0answers
36 views
DelauneyMesh in 4d and higher
Is there any way to find the DelauneyMesh in 4D (or higher)? Its documentation implies that it should be possible "A Delaunay mesh consists of intervals (in 1D), ...
1
vote
0answers
82 views
Periodic Voronoi Mesh in a box
Is it possible to generate a periodic Voronoi Mesh inside a rectangular domain? I would also like to obtain the coordinates of each cell separately so that I can perform further operations on each ...
2
votes
0answers
47 views
0
votes
1answer
58 views
How to find out the number of nodes in the interval of mesh [closed]
I have a mesh created for the femur. I need to apply a total load of 800 N in the range 480 < z < 500. To do this, I need to know the number of nodes in this interval in order to apply Force to ...
7
votes
2answers
360 views
How to add 'border' to Voronoi diagram
Suppose I have a set of points pts, from which I generate a Voronoi diagram VD:
...
3
votes
2answers
109 views
FEM 2D mesh with inclusion
I want to create a FEM mesh with an inclusion, but I want to define the coordinates of the edge nodes manually, since I need the nodes for a problem that requires periodic boundary conditions.
The ...
0
votes
0answers
19 views
modify the elements numbers of a mesh file
I have loaded the mesh of simulation on Mathematica:
geo = Import["geometry.vtk"];
The elements of geo are:
...
0
votes
0answers
38 views
How can I convert such a model into a BoundaryMeshRegion
The obj file is here
As you see, I cannot import such a house model into Mathematica with BoundaryMeshRegion Option.
Import[objFile, "BoundaryMeshRegion"]
So my ...
1
vote
0answers
31 views
How to find intersection of higher dimensional convex hull?
I have often used ConvexHullMesh to obtain a convex hull for 2-d and 3-d points. But when I try to find it for 4-D points I encounter error even for simple cases.
<...
1
vote
1answer
58 views
Represent a Concave Mesh Volume
I programmatically generate a shape, where the top surface is defined by a series of polygons. I generate all the points of the polygon.
...
3
votes
2answers
117 views
Finding mesh elements within a given region
I write a code that generates the following mesh. I would like to find out the elements that completely lie within a certain circular region inside this meshed area. How do I do that?
The code that I ...
3
votes
1answer
43 views
Euler Characteristic of MengerMesh
When I ask Mathematica to give me the Euler characteristic of MengerMesh[1, 3], it returns 16. It seems to me the 1-step Menger sponge has genus 5 and should ...
