Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » Software » comp.soft-sys.matlab

Topic: Delaunay triangulation, Maybe a bug
Replies: 1   Last Post: Jun 10, 2014 2:04 AM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Bruno Luong

Posts: 8,830
Registered: 7/26/08
Re: Delaunay triangulation, Maybe a bug
Posted: Jun 10, 2014 2:04 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

"h" wrote in message <ln5rso$ofb$1@newscl01ah.mathworks.com>...
> Hello everyone,
>
> I use DT = delaunayTriangulation(node) to generate triangles. When I use 15*15 uniform distributed nodes, i get 404 triangular elements. If i am doing the right thing, i think the right answer should be 392 elements.
> I calculated the area of these triangles and I found the area of some triangles are zero.
> Maybe this is a bug. Hope someone can fix it.


I won't consider as BUG, after all delaunay triangulation is a _numerical_ calculation and a regular grid is a singular case for delaunay triangulation: if one of the node move slightly from it's ideal position, the area of the zero-surface becomes > 0.

And I'm not even sure your grid points coordinates can even stored with 100 % accuracy with floating points at the first place.

You just have to deal with this kind of fact in numerical calculation.

Bruno



Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.