Questions tagged [mesh]
Questions on the use and creation of meshes including the use of MeshRegion, ElementMesh, and TetGenLink.
822
questions
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Make uniform mesh with quad elements
I have the following code that generates a finite element mesh with triangular elements which by using command ToQuadMesh I convert to the quadrilateral elements, but I am not able to make the uniform ...
- 337
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2
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671
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How to assign Element marker at boundary edges
How to assign marker at the boundary edges as 1, 2, 3, 4 respectively and set all of the inside elements of region as 0? for example:
Code:
...
user1362
8
votes
4
answers
3k
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Triangulated Mesh from Voronoi Diagram
I want to generate a mesh (using Mathematica 10) in the following manner:
generate a Voronoi diagram, like so:
and then triangulate each individual Voronoi grain, where an edge is formed by ...
- 105
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4
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240
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Shading region under (or over) a curve in horizontal bands
It seems like this should be simple, but I have spent most of the day trying to find a similar example on the web and there appears to be nothing remotely similar. Since I cannot find a way to make ...
- 83
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2
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355
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Contourplots on discrete surfaces
Does anyone know how one can plot contour lines on a meshed surface? For example I would like to be able to plot contour lines indicating lines of equal distance from a given point such as data coming ...
- 4,023
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Finding concave hull for separated small clusters
Data :
data3D = Import[file, "VertexData"];
Graphics3D[Point[data3D]]
How to find concave polygon for separated small clusters.
user1362
8
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3
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419
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How to generate a mesh in an area with curves inside
I would like to know how to generate a mesh inside an area, and be able to find the original curve outline inside the area from the mesh.
For example:
There is a rectangle inside which there is a ...
- 83
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1
answer
866
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Create a voxelized mesh from an STL mesh file
I would like to create a cubic or 3d grid mesh with a constant size for a surface mesh that represents a hollow torus saved in an STL file. mesh
I am import the vertex using:
...
- 599
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2
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491
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ToElementMesh ignores Boundaries and MeshRefinemet
I'm building a mesh of a pit storage in Mathematica which I then export to another FEM-software.
I follow the workflow for creating a ElementMesh from the documentation, but it won't work in the way ...
- 311
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2
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1k
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How to color the triangles of a mesh?
Given a mesh, I want to assign each triangle a color.
I tried to do it in this way:
...
- 677
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2
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536
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How to refine a boundary mesh with MeshRefinementFunction?
MeshRefinementFunction works well to refine elements in a defined spatial domain (here x>0):
...
- 1,231
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3
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How to find ids in a curved line in a finite element mesh?
Previous discussion about this problem has already occurred in this link:
How to get the node id in a specific coordinate in a finite element mesh?
I have the following code that generates a finite ...
- 2,954
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191
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Using Mesh in ContourPlot to find intersections not working
This old answer by @Silvia uses Mesh to find intersections of curves. Unfortunately, it doesn't seem to work in v13.2. For example (based on @JasonB's comment to ...
- 20.2k
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448
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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 ...
- 249
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2
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413
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Computing volume of intersection of two regions
I am trying to compute the volume of intersection of the following two regions:
...
- 193
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235
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Quarter a given triangular meshregion
For a given , examplary simple, triangular meshregion
...
- 53.8k
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190
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Using mesh cell highlighting to override the default rendering of a region
Bug found in V11 and fixed in V12
The default rendering of a region can be rather uninformative. Consider this simple example.
...
- 108k
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answer
334
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Can I trust area calculations over discrete MeshRegions? Flipped triangles, possible visual bug
The following code produces a MeshRegion in two different ways. Unfortunately, the first method produces weird artifacts in ...
- 1,969
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1
answer
940
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Making a 2D hexagonal mesh
There are a lot of answers for how to make a hexagonal mesh on a 3D surface but nothing on how to make a hexagonal mesh on a 2D surface. Can any provide code on how to do so? I am new to mathematica, ...
- 181
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1k
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Meshing the surface of a non-convex object
I would like to mesh the surface of a cloud of points that may not be completely convex, for example the points in this question.
Mathematica does not provide triangulation of 3D points, but there is ...
- 3,332
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2
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323
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Coarse mesh of a sphere
I try to mesh a sphere (examplary) in different qualities, using MaxCellMeasure:
...
- 53.8k
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1
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354
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answer
144
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Make polygons visible in MeshRegions in v11, as they were in v10
In versions 10.x, polygons in mesh regions were clearly outlines:
In version 11.0 they aren't by default.
How do I get back the v10 display so I can see where my polygons are, even in flat faces ...
- 235k
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445
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FEM Simulation: Meshing Two Arbitrary Objects in an "Air" Mesh
Based on this excellent answer to my previous question: FEM: Electric Field between two arbitrary defined shapes
I wanted to try out other shapes:
...
- 3,083
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354
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ConvexHullMesh sometimes excludes valid points from convex hull
I have a sequence of polytopes that I am trying to visualize, and I find that ConvexHullMesh sometimes excludes points from the convex hull, and it does so inconsistently.
In particular, notice these ...
- 221
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ParametricPlot MeshStyle bug in v10?
Bug introduced in 10.0.1 or earlier and fixed in 10.0.2.0
Original Post
The documentation gives the following code and says "Use a red mesh in the x direction and a blue mesh in the y direction:&...
- 2,814
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446
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Identify the Vertices and Lines around the edges of a free surface - Mesh/DiscreteGraphics
To write a mesher that closes a mesh surface using an implied surface from a boundary spline curve and mesh generated using DiscreteGraphics, I need to identify the Vertices and Lines around the edges ...
- 341
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4
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367
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2
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372
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Visualizing region outlines
I want to generate a picture like this, highlight its outlines, don't show extra edges.
The built-in MengerMesh will have extra edges
...
- 5,642
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4
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1k
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Problem with exporting RegionPlot as PDF
I have the following RegionPlot (which code I don't present since it comes from a long expression):
When I right click on it (within the notebook) and try to save ...
- 4,693
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2
answers
243
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Reflection colors are lost on high resolution MeshRegion
Mathematica is able to manage two kinds of reflections :
With a simple color directive (Blue, RBGColor[...]...), one can ...
- 18.5k
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3
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424
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Can one use MeshRefinementFunction to obtain a nonobtuse triangulation?
I have a planar convex polygonal region Rc. I would like to triangulate it such that
every triangle is nonobtuse. I was hoping that the ...
- 4,731
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509
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Meshing a cylindrical geometry with a notch
I have been trying to mesh a cylindrical geometry with a notch. To generate the geometry i use the following command.
...
- 141
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480
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Reduce quality of an imported MeshRegion
Importing STL files using Import results in a MeshRegion composed by the triangulation of the original file, and a similar ...
- 459
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349
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How to Discretize the Following Region Using Reasonable Bounds?
I want to accurately discretize the implicit equation $x^2+x+y^2+\sin(4xy)+\sin(3xy)=3.9$.
To get the whole discretized shape, I'm forced to use oversized bounds ...
- 71
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295
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219
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PeriodicInterpolation does not work in ElementMeshInterpolation
I want to use ElementMeshInterpolation to generate interpolation function with periodic boundary condition.
I use below data as an example
...
- 17.1k
7
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358
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Refining mesh size leads to absurd results for a coupled heat transfer FEM model
I have been recently solving a conjugate heat transfer problem, which involves fully-reversing or reciprocating flow of fluid over a heated block of solid. The problem is 2D and the temperature field ...
- 297
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370
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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 ...
- 1,122
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2
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165
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How to group points based on mesh primitive membership
As a simple example of what I want to do, let's say I have a Voronoi mesh in a $10\times10$ area with $10$ random "seed points":
...
- 1,124
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663
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How do I get a MeshRegion from an obj file, or from Geometry3D
How do I read in an obj file as a MeshRegion so I can e.g. compute its area?
If I just import the object and try Area[O] it ...
- 73
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1k
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How to show wireframes on imported Object / Mesh (.obj file)
I've managed to import a Wavefront (.obj) file and store it in a variable like so:
...
- 173
7
votes
1
answer
463
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Turn a region and points inside that region into a mesh
I have a region defined by a polygon and a few points that are inside that region. I'd like to create a mesh where its boundary is the boundary of the region and the vertices interior to the mesh are ...
- 395
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votes
3
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475
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Trouble with discrete MeshRegions: Integrating over plane slices
I would like to slice a discrete 3D region with a plane, and integrate some field over the resulting 2D region (embedded in 3D). Let me be clear: I do not mean analytical regions (the kind you could ...
- 1,969
7
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2
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296
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Poor/wrong sampling in 1D DiscretizeRegion of splines?
Bug introduced in 10.1 and fixed in 11.3
Context
In relation to this question
I have would like to use splines to define a ...
- 23k
7
votes
2
answers
2k
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How to generate mesh and calculate volume of 3d object?
I saw a couple of posts dicretizing the graphic and generate DelaunayMesh to get volume of 3D object. The issue I'm having is that DelaunayMesh creates a bigger solid covering the original one, ...
- 73
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495
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Mesh at Ticks positions
In a ListPlot3D[ ] I want to have the Mesh at the same positions as the ticks. For some reason this isn't default if both are ...
- 309
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167
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Create a domain for an Hexahedron with the floor replaced with an Indian Burial Mound
I am trying to create an acoustic model domain for a small park that contains an Indian burial mound.
The park is laid out using a 3D cartesian coordinate system in units of meters.
A Hexahedron ...
- 2,279
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289
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7
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335
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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 ...
- 25.3k