# Importing mesh created in gmsh

**URL:** <https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857>\
**Category:** General\
**Created:** [May 31, 2024, 3:23pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857 "2024-05-31T15:23:44Z")\
**Posts on this page:** 20\
**Page:** 1

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [May 31, 2024, 3:23pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/1 "2024-05-31T15:23:44Z")

</div>

hi,

im trying to import a msh files but once i run it gives me the following error  
Traceback (most recent call last):  
File “/home/mirialex/PycharmProjects/fibers/31-05-24.py”, line 11, in   
tet\_data = msh.cell\_data\_dict[“gmsh:physical”][“tetra”]  
KeyError: ‘gmsh:physical’

attaching the file and also the code

```auto
import meshio
from fenics import *

mesh_name = "godplease2"

# Read the mesh file
msh = meshio.read(mesh_name + ".msh")

# Write the volume mesh to XDMF
if "tetra" in msh.cells_dict:
    tet_data = msh.cell_data_dict["gmsh:physical"]["tetra"]
    meshio.write(mesh_name + ".xdmf",
        meshio.Mesh(points=msh.points,
            cells=[("tetra", msh.cells_dict["tetra"])],
            cell_data={"dom_marker": [tet_data]}
        )
    )

# Write the surface mesh to XDMF
if "triangle" in msh.cells_dict:
    tri_data = msh.cell_data_dict["gmsh:physical"]["triangle"]
    meshio.write(mesh_name + "_surf.xdmf",
        meshio.Mesh(points=msh.points,
            cells=[("triangle", msh.cells_dict["triangle"])],
            cell_data={"bnd_marker": [tri_data]}
        )
    )

# Read the volume mesh into FEniCS
mesh = Mesh()
with XDMFFile(mesh_name + ".xdmf") as file:
    file.read(mesh)

# If needed, read the surface mesh (example for boundary conditions)
bnd_mesh = Mesh()
with XDMFFile(mesh_name + "_surf.xdmf") as file:
    file.read(bnd_mesh)

```

since im having a real hard time of create a cylinder inside a box i tried to do it directly in gmsh and then to import it and start analyzing it

so if you have any tips how to continue i would be more that happy to read  
well i cant attach the msh file, but hope that what i wrote here would be helpful

---

<div class="post-metadata">

**Author:** ![Jesus\_Vellojin](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/jesus_vellojin/32/6485_2.png) [@Jesus\_Vellojin](https://fenicsproject.discourse.group/u/Jesus_Vellojin)\
**Post date:** [May 31, 2024, 3:44pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/2 "2024-05-31T15:44:08Z")

</div>

Hi.

Would you mind to share your mesh file so we can test the MWE?

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [May 31, 2024, 3:59pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/3 "2024-05-31T15:59:18Z")

</div>

[https://www.dropbox.com/scl/fi/ymo5o2woy243tn7ma4exn/godplease2.msh?rlkey=1pwyhzykbe9yjeohc1arkjuhu&st=tehu9kc5&dl=0](https://www.dropbox.com/scl/fi/ymo5o2woy243tn7ma4exn/godplease2.msh?rlkey=1pwyhzykbe9yjeohc1arkjuhu&st=tehu9kc5&dl=0)

its not neccerely configured very well cause even the gmsh got stuck for me for a bit

---

<div class="post-metadata">

**Author:** ![Jesus\_Vellojin](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/jesus_vellojin/32/6485_2.png) [@Jesus\_Vellojin](https://fenicsproject.discourse.group/u/Jesus_Vellojin)\
**Post date:** [May 31, 2024, 4:42pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/4 "2024-05-31T16:42:11Z")

</div>

> [@Jesus\_Vellojin](#):
>
> Would you mind to share your mesh file so we can test the MWE?

I just tested with another approach for reading mesh and got the same error. There is something happening in the .geo file. Paste it here please.

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [May 31, 2024, 5:01pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/5 "2024-05-31T17:01:19Z")

</div>

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1 13 1 7  
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73 60 9  
1 14 1 10  
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2 1 2 14  
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2 2 2 14  
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814 156 157 162 69  
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817 163 161 165 61  
818 163 165 161 173  
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$EndElements

---

<div class="post-metadata">

**Author:** ![Jesus\_Vellojin](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/jesus_vellojin/32/6485_2.png) [@Jesus\_Vellojin](https://fenicsproject.discourse.group/u/Jesus_Vellojin)\
**Post date:** [May 31, 2024, 5:05pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/6 "2024-05-31T17:05:22Z")

</div>

This is not the `.geo` file. This is the raw `.msh` file. If you don’t have the `.geo`, then maybe you did your mesh directly using the Gmsh python interface. You could also share that to see what is happening.

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [May 31, 2024, 5:26pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/7 "2024-05-31T17:26:54Z")

</div>

i used the gmsh that is intall on my ubonto  
this is the files that was generated when i saved it  
how can i save different file?

---

<div class="post-metadata">

**Author:** ![Jesus\_Vellojin](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/jesus_vellojin/32/6485_2.png) [@Jesus\_Vellojin](https://fenicsproject.discourse.group/u/Jesus_Vellojin)\
**Post date:** [May 31, 2024, 5:33pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/8 "2024-05-31T17:33:43Z")

</div>

Please note that when your are editing your mesh file on GMSH, the changes are saved on a `.geo` file by default. A `.geo` file looks like the following:

```auto
SetFactory("Built-in");
h=1;
Point(1) = {0, 0, 0, h}; 
Point(2) = {1, 0, 0, h};
Point(3) = {1, 1, 0, h};
Point(4) = {0,1, 0, h};
Line(1) = {1, 2};
Line(2) = {2, 3};
Line(3) = {3, 4};
Line(4) = {4, 1};

//+
Curve Loop(1) = {1, 2, 3, 4};
//+
Plane Surface(1) = {1};
//+
Physical Surface("10",10) = {1};
//+
Physical Curve("1", 1) = {1};
//+
Physical Curve("2", 2) = {2};
//+
Physical Curve("3", 3) = {3};
//+
Physical Curve("4", 4) = {4};

```

You can check on that by clicking on `edit script`  
 ![image](https://global.discourse-cdn.com/free1/uploads/fenicsproject1/original/2X/1/15c96148b9a8d702d949b1c2206f2ba9cc9a9fb4.png)

I suspect there is something wrong when defining the physical groups of your mesh.

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [June 1, 2024, 8:51am UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/9 "2024-06-01T08:51:06Z")

</div>

yes it was something with the files, i managed to import it  
thanks

---

<div class="post-metadata">

**Author:** ![dokken](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/dokken/32/1560_2.png) [@dokken](https://fenicsproject.discourse.group/u/dokken)\
**Post date:** [June 1, 2024, 9:50am UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/10 "2024-06-01T09:50:00Z")

</div>

Please post the solution here, as it would help others resolve similar problems in the future.

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [June 1, 2024, 12:16pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/11 "2024-06-01T12:16:23Z")

</div>

im facing again an issue with the file  
with this error “Error: Couldn’t read file box\_cylinder.msh as either of ansys, gmsh”

those are the files i used [Dropbox](https://www.dropbox.com/scl/fo/tdlzzheuknqequy2mstgt/AINaa2cWibv_6VzdRQHfjWM?rlkey=j22dn5gy13qf0app16u2acv0e&st=m1je15s1&dl=0)

with the same code(updated name file)

```auto
import meshio
from fenics import *

mesh_name = "box_cylinder"

# Read the mesh file
msh = meshio.read(mesh_name + ".msh")

# Write the volume mesh to XDMF
if "tetra" in msh.cells_dict:
    tet_data = msh.cell_data_dict["gmsh:physical"]["tetra"]
    meshio.write(mesh_name + ".xdmf",
        meshio.Mesh(points=msh.points,
            cells=[("tetra", msh.cells_dict["tetra"])],
            cell_data={"dom_marker": [tet_data]}
        )
    )

# Write the surface mesh to XDMF
if "triangle" in msh.cells_dict:
    tri_data = msh.cell_data_dict["gmsh:physical"]["triangle"]
    meshio.write(mesh_name + "_surf.xdmf",
        meshio.Mesh(points=msh.points,
            cells=[("triangle", msh.cells_dict["triangle"])],
            cell_data={"bnd_marker": [tri_data]}
        )
    )

# Read the volume mesh into FEniCS
mesh = Mesh()
with XDMFFile(mesh_name + ".xdmf") as file:
    file.read(mesh)

# If needed, read the surface mesh (example for boundary conditions)
bnd_mesh = Mesh()
with XDMFFile(mesh_name + "_surf.xdmf") as file:
    file.read(bnd_mesh)

```

any idea why? is it something about the way im saving the files?

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [June 1, 2024, 1:48pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/12 "2024-06-01T13:48:05Z")

</div>

i tried to add the following line to the geo files (new\_box\_cylinder)

```auto
//+
SetFactory("Build-in");

```

i uploaded the updated files to this link [Dropbox](https://www.dropbox.com/scl/fo/tdlzzheuknqequy2mstgt/AINaa2cWibv_6VzdRQHfjWM?rlkey=ngf7hgq2i0uw0b8ry9ticf8wu&st=adhe71ca&dl=0)

and i managed to get thorough the first steps but then i got the following error  
/usr/bin/python3.10 /home/mirialex/PycharmProjects/fibers/31-05-24.py  
Traceback (most recent call last):  
File “/home/mirialex/PycharmProjects/fibers/31-05-24.py”, line 36, in   
file.read(mesh)  
RuntimeError:

\*\*\* -------------------------------------------------------------------------  
\*\*\* DOLFIN encountered an error. If you are not able to resolve this issue  
\*\*\* using the information listed below, you can ask for help at

* * *

\*\*\* [https://fenicsproject.discourse.group/](https://fenicsproject.discourse.group/)

* * *

\*\*\* Remember to include the error message listed below and, if possible,  
\*\*\* include a _minimal_ running example to reproduce the error.

* * *

\*\*\* -------------------------------------------------------------------------  
\*\*\* Error: Unable to open XDMF file.  
\*\*\* Reason: XDMF file “new\_box\_cylinder.xdmf” does not exist.  
\*\*\* Where: This error was encountered inside XDMFFile.cpp.  
\*\*\* Process: 0

* * *

\*\*\* DOLFIN version: 2019.2.0.13.dev0  
\*\*\* Git changeset: ubuntu  
\*\*\* -------------------------------------------------------------------------

Process finished with exit code 1

any idea why?

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [June 1, 2024, 6:55pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/13 "2024-06-01T18:55:24Z")

</div>

i also tried this (posted by @dokken few years ago

```auto
import meshio

msh = meshio.read("new_box_cylinder.msh")

def create_mesh(mesh, cell_type, prune_z=False):
    cells = mesh.get_cells_type(cell_type)
    cell_data = mesh.get_cell_data("gmsh:physical", cell_type)
    out_mesh = meshio.Mesh(points=mesh.points, cells={
                           cell_type: cells}, cell_data={"name_to_read": [cell_data]})
    if prune_z:
        out_mesh.prune_z_0()
    return out_mesh

tetra_mesh = create_mesh(msh, "tetra")
triangle_mesh = create_mesh(msh, "triangle")
meshio.write("mesh.xdmf", tetra_mesh)

meshio.write("mf.xdmf", triangle_mesh)

```

error  
/usr/bin/python3.10 /home/mirialex/PycharmProjects/fibers/1-06-24.py  
Traceback (most recent call last):  
File “/home/mirialex/PycharmProjects/fibers/1-06-24.py”, line 17, in   
tetra\_mesh = create\_mesh(msh, “tetra”)  
File “/home/mirialex/PycharmProjects/fibers/1-06-24.py”, line 9, in create\_mesh  
cell\_data = mesh.get\_cell\_data(“gmsh:physical”, cell\_type)  
File “/usr/lib/python3/dist-packages/meshio/\_mesh.py”, line 249, in get\_cell\_data  
return np.concatenate(  
File “\< **array\_function** internals\>”, line 5, in concatenate  
ValueError: need at least one array to concatenate

Process finished with exit code 1

how can i make sure that my tetra elements are defined as needed?

---

<div class="post-metadata">

**Author:** ![Jesus\_Vellojin](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/jesus_vellojin/32/6485_2.png) [@Jesus\_Vellojin](https://fenicsproject.discourse.group/u/Jesus_Vellojin)\
**Post date:** [June 2, 2024, 3:08am UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/14 "2024-06-02T03:08:58Z")

</div>

First you post about `box_cylinder` and then about `new_box_cylinder`. Please, try to simplify your debugging as much as possible before posting because we might end up solving a question you have already solved by yourself, or getting lost in the post.

Regarding `box_cylinder`, you are using Recombine in the extrude, which will produce elements that are not supported in Legacy FEniCS. By removing that, you end up with tetrahedrons, as desired. Also, by extruding your composite mesh, your are creating two volumes: one for the cylinder, and one for the “exterior”. However, you are defining only a physical volume `1` which is the cylinder. I don’t know if that was intentional. The following `.geo` file stores Volume 1 and 2 as single physical volume:

```auto
SetFactory("Built-in");
//+
Point(1) = {0, 0, 0, 1.0};
//+
Point(2) = {0, 0.2, .2, 1.0};
//+
Point(7) = {0, 0.2, 0, 1.0};
//+
Point(8) = {0, 0, 0.2, 1.0};
//+
Point(10) = {0, 0.1, 0.1, 1.0};
//+
Point(13) = {0, 0.15, 0.1, 1.0};
//+
Point(14) = {0, 0.1, 0.15, 1.0};
//+
Point(15) = {0, 0.1, 0.05, 1.0};
//+
Point(16) = {0, 0.05, 0.1, 1.0};
//+
Circle(1) = {14, 10, 13};
//+
Circle(2) = {13, 10, 15};
//+
Circle(3) = {15, 10, 16};
//+
Circle(4) = {16, 10, 14};
//+
Line(5) = {8, 2};
//+
Line(6) = {2, 7};
//+
Line(7) = {7, 1};
//+
Line(8) = {1, 8};
//+
Curve Loop(1) = {5, 6, 7, 8};
//+
Curve Loop(2) = {4, 1, 2, 3};
//+
Plane Surface(2) = {2};
//+
Plane Surface(3) = {1, 2};

//+
Extrude {1, 0, 0} {Surface{2}; Surface{3}; Layers {10};
}
//+
Physical Surface("top", 110) = {43};
//+
Physical Surface("bottum", 111) = {51};
//+
Physical Surface("left", 112) = {47};
//+
Physical Surface("right", 113) = {55};
//+
Physical Surface("front", 114) = {3};
//+
Physical Surface("back", 115) = {72};
//+
Physical Surface("cylinder_left", 116) = {2};
//+
Physical Surface("cylinder_right", 117) = {30};
//+
Physical Volume("body", 118) = {1,2};

```

Using the code from @dokken works with no issue in this mesh.

```auto
import meshio

msh = meshio.read("box_cylinder.msh")

def create_mesh(mesh, cell_type, prune_z=False):
    cells = mesh.get_cells_type(cell_type)
    cell_data = mesh.get_cell_data("gmsh:physical", cell_type)
    out_mesh = meshio.Mesh(points=mesh.points, cells={
                           cell_type: cells}, cell_data={"name_to_read": [cell_data]})
    if prune_z:
        out_mesh.prune_z_0()
    return out_mesh

tetra_mesh = create_mesh(msh, "tetra")
triangle_mesh = create_mesh(msh, "triangle")
meshio.write("mesh.xdmf", tetra_mesh)

meshio.write("mf.xdmf", triangle_mesh)

```

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [June 2, 2024, 6:01am UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/15 "2024-06-02T06:01:13Z")

</div>

hi, i have tried to use what you sent me (the updated code for box\_cylinder) in both of the codes and this is the error i got  
Error: Couldn’t read file new\_box\_cylinder\_wc.msh as either of ansys, gmsh

i have use the updated file in the dropbox [Dropbox](https://www.dropbox.com/scl/fo/tdlzzheuknqequy2mstgt/AINaa2cWibv_6VzdRQHfjWM?rlkey=ngf7hgq2i0uw0b8ry9ticf8wu&st=aj3q8uhn&dl=0) called new\_box\_cylinder\_wc  
btw, when you are importing my files , are you using new\_box\_cylinder\_wc.msh or new\_box\_cylinder\_ws?

---

<div class="post-metadata">

**Author:** ![Jesus\_Vellojin](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/jesus_vellojin/32/6485_2.png) [@Jesus\_Vellojin](https://fenicsproject.discourse.group/u/Jesus_Vellojin)\
**Post date:** [June 3, 2024, 1:24am UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/16 "2024-06-03T01:24:45Z")

</div>

> [@Mirialex](#):
>
> hi, i have tried to use what you sent me (the updated code for box\_cylinder) in both of the codes and this is the error I got  
> Error: Couldn’t read file new\_box\_cylinder\_wc.msh as either of ansys, gmsh

Maybe the `.msh` is being malformed because I tested your `.msh` file from Dropbox and got the same error. What version of GMSH are you using?. How are you saving your files?.

You can save your mesh by running the following command from a terminal inside your meshes directory and try to read them again.

```auto
gmsh -3 box_cylinder.geo -o box_cylinder.msh

```

> [@Mirialex](#):
>
> i have use the updated file in the dropbox [Dropbox](https://www.dropbox.com/scl/fo/tdlzzheuknqequy2mstgt/AINaa2cWibv_6VzdRQHfjWM?rlkey=ngf7hgq2i0uw0b8ry9ticf8wu&st=aj3q8uhn&dl=0) called new\_box\_cylinder\_wc  
> btw, when you are importing my files , are you using new\_box\_cylinder\_wc.msh or new\_box\_cylinder\_ws?

I did not used either. I used `box_cylinder`.

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [June 3, 2024, 12:32pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/17 "2024-06-03T12:32:21Z")

</div>

my version is 4.11.1  
im saving it via files-\>export-\>  
 ![image](https://global.discourse-cdn.com/free1/uploads/fenicsproject1/original/2X/1/1a2f3fcd770a80b06cab340db08cad25003dd55d.png)  
or file-\> save mesh  
and for the geo it just being saved

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [June 3, 2024, 12:35pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/18 "2024-06-03T12:35:58Z")

</div>

also, if i do want to create 2 volumes (i want to create two bodies, the cylinder and the box) its possible?

---

<div class="post-metadata">

**Author:** ![Mirialex](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/mirialex/32/5890_2.png) [@Mirialex](https://fenicsproject.discourse.group/u/Mirialex)\
**Post date:** [June 3, 2024, 1:04pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/19 "2024-06-03T13:04:43Z")

</div>

> [@Jesus\_Vellojin](#):
>
> `gmsh -3 box_cylinder.geo -o box_cylinder.msh`

i tried that and it read my file without any issue and exported my exml file so thats great, thank you!

now what i want to ask is how can i create two bodies with the exml (2 volums) i need one body to be the cylinder inside the second body the box.

i tried to do it like this but in paraview i see only the box(with the same code i posted before)

```auto
// Gmsh project created on Mon Jun 03 15:42:59 2024
//+
SetFactory("OpenCASCADE");
Box(1) = {0, 0, 0, 1, 0.2, 0.2};
//+
Cylinder(2) = {0, 0.1, 0.1, 1, 0, 0, 0.05, 2*Pi};
//+
Curve Loop(10) = {2, -3, -4, 1};
//+
Plane Surface(10) = {10};
//+
Curve Loop(11) = {2, 12, -6, -10};
//+
Plane Surface(11) = {11};
//+
Curve Loop(12) = {11, -8, -9, 4};
//+
Plane Surface(12) = {12};
//+
Curve Loop(14) = {1, 10, -5, -9};
//+
Plane Surface(13) = {14};
//+
Curve Loop(15) = {8, 7, -6, -5};
//+
Plane Surface(14) = {15};
//+
Curve Loop(16) = {12, -7, -11, 3};
//+
Plane Surface(15) = {16};
//+
Physical Surface("left", 17) = {1};
//+
Physical Surface("right", 18) = {2};
//+
Physical Surface("up", 19) = {4};
//+
Physical Surface("down", 20) = {3};
//+
Physical Surface("front", 21) = {6};
//+
Physical Surface("back", 22) = {5};
//+
Physical Volume("body", 23) = {1};
//+
Physical Volume("body", 24) = {2};

```

 ![image](https://global.discourse-cdn.com/free1/uploads/fenicsproject1/original/2X/f/f2fb5db98159900565605b4b2d9f564e92917e3d.png)

---

<div class="post-metadata">

**Author:** ![dokken](https://yyz2.discourse-cdn.com/free1/user_avatar/fenicsproject.discourse.group/dokken/32/1560_2.png) [@dokken](https://fenicsproject.discourse.group/u/dokken)\
**Post date:** [June 3, 2024, 1:12pm UTC](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857/20 "2024-06-03T13:12:36Z")

</div>

This is a pure gmsh question, which I think is better suited for the GMSH developers.  
You can also look into the gmsh tutorials (chapter 2 of: [https://gmsh.info/dev/doc/texinfo/gmsh.pdf](https://gmsh.info/dev/doc/texinfo/gmsh.pdf))

[Next page](https://fenicsproject.discourse.group/t/importing-mesh-created-in-gmsh/14857.md?page=2)