[Gmsh] one noded elements

Christophe Geuzaine cgeuzaine at ulg.ac.be
Tue Nov 20 18:35:19 CET 2007

Thomas S. Hille wrote:
> Hello,
> I have just installed the newest version of gmsh (2.0.8), before I used 1.6.
> I see that you have changed the format of the msh file to what is now 
> known as 2.0. Since I have to bring the mesh data into my own format I 
> expect a specific format of this file as an input to my own conversion 
> algorithm. Fortunately, I found out that when saving the file via Save 
> As.. I have the choice for the old format 1.0.
> The problem is just that this is still different to what I was used to. 
> Namely, the msh file contains now in the beginning ot the element list 
> one noded elements. I have not had this output before. The amount of one 
> noded elements is equal to the amount of points that I added 
> constructing the geo file.
> How do I get rid of this output? Is it my mistake (e.g. somewhere a 
> different setting) that output in the msh format 1.0 within gmsh 2.0.8 
> is different to the output format I was used to with gmsh 1.6?

Hi Thomas - The only difference is that Gmsh 2.0 now saves all element 
types in a consistent manner:

* if no physical entities are defined, Gmsh saves all the elements in 
the mesh (0D, 1D, 2D and 3D)

* if physical entities are defined, only the elements belonging to 
physical entities are saved.

To disable saving 1-noded (0D) elements, just define physical entities 
for the ones you want to save.

Hope this helps,


> Thanks for your support,

Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science