Questions tagged [partitioning]
The partitioning tag has no usage guidance.
27 questions
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Explicit polynomial for quadratic elements? (FEM)
In this resource the linear (barycentric) elements are explicitly given:
The geometry placement of higher order elements is also given but not expression for the polynomial of $P_2$ is given. I am ...
1
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1
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102
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Mesh decomposition using coordinate bisection
I am currently trying to understand the mesh partitioning using coordinate bisection method. The general idea is clear: Looking at the coordinates (either X or Y or Z direction) and splitting the ...
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43
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Simultaneously partition all mesh elements (nodes, edges and cells) among processors
The numerical method that I'm implementing stores various fields in various elements of an unstructured triangular mesh. Data may be stored in cells, nodes and even edges of the mesh. For a parallel ...
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Looking for Partinioning Algorithms allowing for Constraints
What algorithms exist that partition the domain according to a black box evaluation function (possibly subject to some assumptions)?
Examples
Simple Example
To better exaplain we consider as our ...
2
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1
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227
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Partition mesh into predetermined submeshes
I have a mesh already partitioned into disjoint groups of cells. What I want to achieve is the following.
Obtain the adjacency graph for the cell groups.
Partition the mesh, i.e. generate submeshes ...
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0
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175
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Solving a linear system with block-banded matrix
It is required to solve a linear system $Ax=b$, where the matrix $A$ is symmetric, all the variables and coefficients are real.
The structure of $A$ is
\begin{equation}
A = \begin{pmatrix} A_{11} &...
2
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2
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844
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Visualization of Quad/Octree data Structures
I have a simple C++ quadtree implementation. The implementation subdivides node into four children as if there is more than one point in that particular node. At the moment I want to visualize how ...
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0
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299
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Metis: how to use and tutorial recommendation
I am new to METIS and trying to use it in my fortran code. I read the manual online. But still, I am not sure about how to implement it my code. I tried the test cases in the graphs directory. For ...
4
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1
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What is the difference between recursive bisection and direct k-way partition?
The usual problem of graph partitioning is to split a graph (or a mesh) into two partitions.
According to its Github repository's README file, KaHyPar supports both recursive bisection and direct k-...
0
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1
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157
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Linear algebra of the inertial partition algorithm
You can find the description of the inertial partition algorithm either in [1] or [2].
I think, I understood the main idea behind this algorithm:
We have the spatial coordinates of points that ...
1
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0
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29
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How group similar data in a single classes and reduce the error
I have vehicles gps information in my real time traffic application. Averaging that information I know the speed of every road at any time. The problem is that is too much data to send back to the ...
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Automatic classification of a family of 2D contours or closed surfaces in 3D
I am computing some partitions in my work and would like to be able to extract informations in an automatic way when given a certain partition structure. To see what I have in mind, look at the photos ...
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simple and fast graph-clustering for paralelization of finite element simulations
I'm learning to use OpenCL to optimize some of my simulations. I realized that I need some sort of Graph-clustering or graph-partitioning to exploit efficiently local memory for un-ordered meshes.
...
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0
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113
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Mesh partitioner with user-defined overlap
I am looking for a mesh partitioner, where I can specify overlap, for example h = 3.
I have looked into metis, but I wasn't able to find such a functionality.
Is there any other package which ...
0
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1
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197
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how to partition a graph(matrix) into subdomains with different sizes
i am studying the solver for PageRank problems which drived from the web link graph.
I have tried using METIS to divided the matrix into subdomains, but METIS can only produce subdomains with nearly ...
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1
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79
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Particle mesh Ewald: recommended splitting into short and long range
Particle mesh Ewald method for acceleration of solving pairwise interaction by long range forces (electrostatic, gravitational ... ) seem to be very general and easy to implement. The basic principle ...
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0
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43
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Optimal partition - variable number of parts
Suppose I have a box $D \subset \Bbb{R}^2$ (compact set). Denote $\mathcal{P}= \{ (\Omega_1,...,\Omega_n) : \bigcup_{i=1}^n \Omega_i = D,\ \Omega_i \cap \Omega_j =\emptyset\}$ the family of partitions ...
5
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1
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Why dual graph for mesh partitioning
Software such as ParMetis or PTScotch partition a graph. When one wants to use it for mesh partitioning (for example for FEM), a dual graph whose vertices represent cells of the original mesh is ...
3
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0
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117
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Partitioning Data for Multiple Regression Lines
We're all familiar with traditional least-squares method for constructing a straight line through a set of data points. The question is: suppose I show you a scatter plot which clearly is suggestive ...
4
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1
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895
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metis partitioning for structured multi-block grids
Metis is purpose-built for partitioning graphs and unstructured meshes one uses in finite element/volume methods, and it works great for this.
I have a 3D structured multi-block topology, where each $...
5
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3
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992
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implicit vs. explicit domain decomposition methods
I've been working on a finite element code on unstructured methods, which I've parallelized using the Schur complement method. Here's a summary of how I did it:
Assign each triangle of the mesh to a ...
7
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1
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176
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Random access random permutations
I have a large number of parallel processes and a large integer $n$, and want to randomly partition the integers $[0,n)$ among the processes with only $O(1)$ communication.
One nice way to do this ...
4
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1
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274
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Mesh partitioner that assures non empty subdomain?
Does some of you know a mesh partitioner that assures non empty subdomains? For METIS, ParMETIS and Zoltan this is not the case.
3
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1
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159
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Single nodes after mpmetis partitioning
I was checking partitioning capabilities of Metis (mpmetis) when I noticed, that it leaves two single nodes. I have marked them in red
Have you seen something similar or maybe it is my mistake?
The ...
3
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1
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260
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Looking for parMetis visualizer?
Is there any visualizer for parMetis (mpmetis), which can visualize FEM mesh grids after partitioning?
2
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2
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1k
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Mesh domain decompositions / mesh partitioning
I have some experience with mpmetis from METIS. It is pretty good software which offers unstructured mesh grid partitioning. But obtained results always minimize edgecuts or total communication volume....
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3
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357
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Desktop software with HPC resources for back end number crunching
Our workgroup produces a desktop application that simulates building energy performance. It is a .NET application and when the user is running a lot of simulations, they can be quite time consuming. ...