FLselect
by Tim C. Lueth, SG-Lib Toolbox: SolidGeometry 5.6 - Auxiliary function
Introduced first in SolidGeometry 3.4, Creation date: 2017-02-14, Last change: 2025-09-14
returns all neighbor facets of ONE SINGLE vi
Description
Some functions such as MLofSG process a complete solid. Nevertheless, finally, only facets that are linked to a vertex are required. FLselect returns form a FL the index of all facts that contain vi, the reduced facet list, and a facet list that is sorted in a way that the FL starts always with vi
See Also: ELselect
, FLofVLFLvi
, FLofVLFLfi
Example Illustration
Syntax
[FLv,fi,FLs]=FLselect(FL,vi)
Input Parameter
FL: | | Facet list |
vi: | | index of vertex |
Output Parameter
FLv: | | reduced facet list |
fi: | | facet index of FL |
FLs: | | FL with sortet rows |
Examples
[VL,FL]=VLFLcone(30,'',6)
[FLv,fi,FLs]=FLselect(FL,3)
Copyright 2017-2025 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 algorithm is designed to process a facet list (FL) and identify all facets that are connected to a specific vertex index (vi). It returns a reduced facet list, the indices of the original facets containing the vertex, and a sorted facet list.
Input Parameters
- FL: A matrix representing the facet list, where each row corresponds to a facet defined by three vertex indices.
- vi: An integer representing the index of the vertex for which neighboring facets are to be found.
Output Results
- FLv: A reduced facet list containing only the facets that include the vertex vi.
- fi: A logical array indicating which facets in the original list contain the vertex vi.
- FLs: A sorted facet list where each row starts with the vertex vi.
Algorithm Steps
- Check if the length of vi is 1, ensuring that only a single vertex index is processed.
- Create logical arrays f1, f2, and f3 to identify facets where vi is the first, second, or third vertex, respectively.
- Combine f1, f2, and f3 using a logical OR operation to create fi, which marks all facets containing vi.
- Extract the rows from FL where fi is true to form FLv, the reduced facet list.
- Construct FLs by rearranging the rows of FL such that each row starts with vi, using f1, f2, and f3 to determine the order.
Algorithm explaination created using ChatGPT on 2025-08-19 01:11. (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