[Gmsh] Triangles in .msh file

[Gmsh User]

mianzhi <wangmianzhi1 at ...> writes:

> 
> Hello,
> Hopefully my answer would be helpful.
> 1. All Tri.s are on the boundary.
> 2. The 2nd "tag" of each Tri., the "geometric entity", tells you which 
> boundary surface the Tri. belongs to.
> (find "number-of-tags" on this page 
> http://geuz.org/gmsh/doc/texinfo/gmsh.html )
> 3. You may see the "geometric entity index" of all boundary surfaces in 
> gui of gmsh via enabling "Tools/Options/Geometry/Surface numbers".
> 
> Mianzhi


I think I am not understanding what you meant my Tri.s . Is this an operator or
something?

Could you clarify what you meant by that? 

Just to give you more info about what I am actually doing, after I finish
meshing a geometry, I save the mesh in .msh file format and export it to MATLAB.
This is the only file I have, and this file clearly contains nodal numbers and
coordinates of bunch of triangles along with that of points, lines and
tetrahedrons. I need nodal numbers and coordinates of SURFACE TRIANGLES ONLY,
and my question was whether the triangles appearing in .msh file are indeed the
SURFACE TRIANGLES ONLY. 

I am sorry if this is what you meant, but a clarification would certainly help.

Thanks for replying!

~Gmsh User