[Gmsh] 2D mesh error message

Mikhail Artemyev artemiev.mikhail at gmail.com
Fri Jan 16 16:02:14 CET 2015


Hi Yao-Cheng,

I was able to build the meshes for all these 3 files and RandomFactor=1e-6:
10K on Linux Mint 64bit, gmsh 2.8.5
50K on Linux Mint 64bit, gmsh 2.8.5
100K on Mac OS X 64bit, gmsh 2.8.4 (but I think it will work on Linux as 
well)

Best,
Mikhail


On 01/16/2015 01:11 AM, Yao-Cheng Tien wrote:
> Hi Mikhail,
>
> I have attached three more testcases. I have tried to embed 10k, 50k, 
> and 100k lines(with length 1) to a surface separately. The element 
> size is 1.
>
> The issue is that the 2d mesh(meshAdapt) works for 10k and 50k after 
> setting the Mesh.RandomFactor to 1e-6. However, the 100k one fails 
> even when I increase the Mesh.RandomFactor to 1e-4. The error message 
> is "Identical points in triangulation: increase element size or 
> Mesh.RandomFactor"
>
> My questions are:
> 1. Is there any limit about the number of embedded lines? 100k 
> embedded lines are too much?
> 2. Any setting I missed to make it work?
>
> Thank you!
>
> Best,
> YC
>
> On Thu, Jan 15, 2015 at 8:59 AM, Yao-Cheng <yaocheng2010 at gmail.com 
> <mailto:yaocheng2010 at gmail.com>> wrote:
>
>     Hi Mikhaul,
>
>     My mistake. I'm trying different settings to fix that actually.
>     The original geo file indeed has lc=1 but still fails. I have also
>     tried lc=0.1 0.5.
>
>     I know it's ok if I have only 1 line or even 10k lines. But in my
>     situation, I probably need to have up to 1 million lines. Any
>     suggestion?
>
>     Thank you.
>
>     Best,
>     YC
>     > On Jan 15, 2015, at 6:26 AM, Mikhail Artemyev
>     <artemiev.mikhail at gmail.com <mailto:artemiev.mikhail at gmail.com>>
>     wrote:
>     >
>     > Hi,
>     >
>     > Your lines have length 1, while the characteristic length of the
>     mesh you defined was 10.
>     > What happens if you set lc = 1?
>     > With only one line embedded it works fine for me (and
>     RandomFactor=1e-8), but I didn't try for all 50K of them.
>     >
>     > Best,
>     > Mikhail
>     >
>     >
>     >> On 01/15/2015 02:29 AM, gmsh-request at ace20.montefiore.ulg.ac.be
>     <mailto:gmsh-request at ace20.montefiore.ulg.ac.be> wrote:
>     >> Hi,
>     >>
>     >> I have encountered the issue "*Identical points in
>     triangulation: increase
>     >> element size or Mesh.RandomFactor*" in my 2D geometry file.
>     After looking
>     >> into previous support mails, I changed the Mesh.RandomFactor to
>     1e-8, 1e-7
>     >> until 1e-2. However, it still fails. Could you tell me what
>     other option I
>     >> should try since I am pretty new to Gmsh?
>     >>
>     >> My geometry is simple. I have a surface with size 1100 by 210.
>     Also, there
>     >> are 50K lines with length 1 embedded in that surface.
>     >>
>     >> Thanks for your help in advance!
>     >>
>     >> Best,
>     >> YC
>     >
>
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20150116/c1ef1c4b/attachment.html>