VLELofTR
by Tim C. Lueth, SG-Lib Toolbox: SolidGeometry 5.6 - TR/Tetrahedrons
Introduced first in SolidGeometry 2.4, Creation date: 2015-08-15, Last change: 2025-09-14
returns the edge constraints of a triangulation
Description
returns the edge constraints of a triangulation
Example Illustration
Syntax
[VL,EL,FL]=VLELofTR(TR)
Input Parameter
TR: | | Triangulation (nx4 or nx3 or nx2) |
Output Parameter
VL: | | Vertex List (Point List) |
EL: | | Facet List (Constraints) |
FL: | | Facet List (ConnectivityList or freeBoundary) |
Examples
[VL,FL]=VLELofTR(exp_2014_12_23 (SGsample(16))); close all; VLFLfigure; view(-30,30); VLFLplots(VL,FL);
Copyright 2015-2025 Tim C. Lueth. All rights reserved. The code is the property of Tim C. Lueth and may not be redistributed or modified without explicit written permission. This software may be used free of charge for academic research and teaching purposes only. Commercial use, redistribution, modification, or reverse engineering is strictly prohibited. Access to source code is restricted and granted only under specific agreements. For licensing inquiries or commercial use, please contact: Tim C. Lueth
Algorithm (Workflow)
This function, VLELofTR, is designed to extract and return the edge constraints of a given triangulation. It is part of the SG-Library and was developed by Tim Lueth on August 15, 2015. The function processes a triangulation input and outputs lists of vertices, edges, and facets.
Input Parameters
- TR: This is the triangulation input, which can be in the form of an nx4, nx3, or nx2 matrix. It represents the geometric structure that the function will process.
Output Results
- VL: Vertex List, which is essentially a list of points that make up the vertices of the triangulation.
- EL: Edge List, which contains the constraints or edges of the triangulation.
- FL: Facet List, which provides the connectivity list or free boundary of the triangulation.
Algorithm Steps
- Initialize empty lists for
EL, VL, and FL.
- Check if the input
TR has a field named 'Constraints'. If not, issue a warning that the triangulation has no constraint edges but may have feature edges, and then exit the function.
- If the 'Constraints' field is empty, issue the same warning and exit the function.
- Assign the points from
TR.Points to VL.
- Assign the constraints from
TR.Constraints to EL.
- Assign the connectivity list from
TR.ConnectivityList to FL.
- If no output arguments are specified (
nargout==0), create a figure using SGfigure and plot the vertices and edges using VLELplot.
- Adjust the view of the plot based on the dimensionality of the vertex list. If the vertex list is 2D, set the view to (0,90). Otherwise, set it to (-30,30).
The function is straightforward, focusing on extracting and displaying the structural components of a triangulation. It checks for the presence of constraints and handles cases where they are absent by issuing warnings.
Algorithm explaination created using ChatGPT on 2025-08-18 23:59. (Please note: No guarantee for the correctness of this explanation)
Last html export of this page out of FM database by TL: 2025-09-21