File Exchange

image thumbnail

Assign connectivity ID to 2D triangular mesh

version 1.2.0.0 (2.69 KB) by David Gingras
This function assigns an ID based on the connectivity for each cell of a 2D triangular mesh.

1 Download

Updated 19 Jun 2009

View Version History

View License

This function takes an unrestricted triangulation (only the list of triangles, not the node coordinates) and assigns an ID to each group of triangles. If some cells are connected together, each cell of that group will have the same ID. It works like the connectivity-filter of the graphical library VTK.

function groupID=connectivityTri(TRI)
Input :
"TRI" is mx3 matrix which is the standard list of index of vertices
Output :
"groupID" is mx1 matrix which is the list of ID-group of each cell

Simple example :

X=[2 1 3 2 5 5 8 6 7 5 8 9 10 12 10 12 13 15 1 0 2 1];
Y=[2 4 4 6 6 8 8 4 2 2 4 6 8 7 5 5 3 2 7 8 8 9];
Z=zeros(size(X));
TRI=[1 2 3;2 4 3;4 3 5;5 6 7;10 8 9;8 9 11;12 13 14;15 16 17;17 16 18;4 6 5;20 19 21;22 21 20];
groupID=connectivityTri(TRI);

trisurf(TRI,X,Y,Z,groupID) (the screenshot of the soumission)

Cite As

David Gingras (2021). Assign connectivity ID to 2D triangular mesh (https://www.mathworks.com/matlabcentral/fileexchange/24005-assign-connectivity-id-to-2d-triangular-mesh), MATLAB Central File Exchange. Retrieved .

Comments and Ratings (1)

Nice work, fast and accurate. It will let me save a lot of time.

MATLAB Release Compatibility
Created with R2009a
Compatible with any release
Platform Compatibility
Windows macOS Linux
Acknowledgements

Inspired by: Toolbox Wavelets on Meshes

Inspired: Remove Unconnected Triangle

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!