Dear Users and Developers

I am trying to read in a simple mesh created using Gmsh, which has two Physical regions.
I use the example programme ex1.cc to read the .msh file, and write it out as another
.msh file, i.e ./ex1 -d 2 in.msh out.msh.

I find that the output of ex1.cc mentions n_subdomains()=1, though there are two physical
regions.

Mesh Information:
  mesh_dimension()=2
  spatial_dimension()=3
  n_nodes()=45
    n_local_nodes()=45
  n_elem()=32
    n_local_elem()=32
    n_active_elem()=32
  n_subdomains()=1
  n_processors()=1
  processor_id()=0

Also, when I look at the out.msh file, I notice that there is only one Physical region!

I have tried with both the Gmsh v1 and v2 formats. My libmesh version corresponds
to the svn trunk.

I have searched extensively on the archives, but didnt find a solution to my problem.
Can someone with experience with Gmsh import throw more light on this issue?

Thanks.
Regards

Arvind Ajoy



The Gmsh in.geo file is as under ........

==================================================================
a = 1;

// 4    3    6
// +    +    +
//
//
//
//
// +    +    +         
// 1    2    5

Point(1) = {0, 0, 0};
Point(2) = {a, 0, 0} ;
Point(3) = {a, a, 0} ;
Point(4) = {0, a, 0} ;
Point(5) = {2*a,0, 0};
Point(6) = {2*a,a, 0};

Line(1) = {1,2} ;
Line(2) = {3,2} ;
Line(3) = {3,4} ;
Line(4) = {4,1} ;
Line(5) = {2,5} ;
Line(6) = {5,6} ;
Line(7) = {6,3} ;

Line Loop(8) = {4,1,-2,3} ;
Line Loop(9) = {5,6,7,2};
Ruled Surface(10) = {8} ;
Ruled Surface(11) = {9} ;

Transfinite Line{4} = 5 ;
Transfinite Line{2} = 5 ;
Transfinite Line{1} = 5 ;
Transfinite Line{3} = 5 ;
Transfinite Line{5} = 5 ;
Transfinite Line{6} = 5 ;
Transfinite Line{7} = 5 ;

Transfinite Surface{10} = {1,2,3,4};
Transfinite Surface{11} = {2,5,6,3};
// (Note that the list on the right hand side refers to points, not
// curves.

// Recombine the triangles into quads
Recombine Surface{10};
Recombine Surface{11};

Physical Surface (100) = {10};
Physical Surface (200) = {11};
Physical Line (300) = {1,5,6,7,3,4};
================================================================