[Gmsh] export only quadrangle elements in a mesh

[Umut Tabak]

Dear all,

I am a rather new user of gmsh who spent the all sunday afternoon for a 
problem in gmsh. I would like to export/write only quadrangle mesh 
information, binary or ascii does not matter. However when I use the 
t6.geo tutorial file with some modifications I am getting as the output 
all the relevant element information. I only need the element 
connectivities for real elements(in a finite element context, I only 
need the quadrangles/triangles) where I can continue to numerical 
gaussian integration to generate element matrices in my own code. Is 
there a way to somehow export only this information or is that possible 
to make a seperate section in the output file furnished with this 
information only? For instance only elements  9 to 12 so that I will 
have the necessary connectivity...

Thanks in advance for the replies...

Output of a my simple grid information

$MeshFormat
2 0 8
$EndMeshFormat
$PhysicalNames
1
100 "My fancy surface label"
$EndPhysicalNames
$Nodes
9
1 0 0 0
2 0.1 0 0
3 0.1 0.3 0
4 0 0.3 0
5 0.04999999999991952 0 0
6 0.1 0.150000000000104 0
7 0.05000000000012142 0.3 0
8 0 0.150000000000104 0
9 0.05000000000000205 0.1500000000000936 0
$EndNodes
$Elements
12
1 15 3 1 1 0 1
2 15 3 1 2 0 2
3 1 3 99 1 0 1 5
4 1 3 99 1 0 5 2
5 1 3 99 2 0 3 6
6 1 3 99 2 0 6 2
7 1 3 99 4 0 4 8
8 1 3 99 4 0 8 1
9 3 3 100 6 0 1 5 9 8
10 3 3 100 6 0 8 9 7 4
11 3 3 100 6 0 5 2 6 9
12 3 3 100 6 0 9 6 3 7
$EndElements

--
U.T.
--
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