# Transitioning from mesh.xml to mesh.xdmf, from dolfin-convert to meshio

**URL:** <https://fenicsproject.discourse.group/t/transitioning-from-mesh-xml-to-mesh-xdmf-from-dolfin-convert-to-meshio/412>\
**Category:** mesh\
**Created:** [March 22, 2019, 9:01am UTC](https://fenicsproject.discourse.group/t/transitioning-from-mesh-xml-to-mesh-xdmf-from-dolfin-convert-to-meshio/412 "2019-03-22T09:01:33Z")\
**Posts on this page:** 1\
**Showing post:** 181

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**Author:** ![rkailash](https://avatars.discourse-cdn.com/v4/letter/r/848f3c/32.png) [@rkailash](https://fenicsproject.discourse.group/u/rkailash)\
**Post date:** [October 21, 2021, 5:47pm UTC](https://fenicsproject.discourse.group/t/transitioning-from-mesh-xml-to-mesh-xdmf-from-dolfin-convert-to-meshio/412/181 "2021-10-21T17:47:56Z")

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Thank you. This works perfectly.  
If anyone is interested in adapting this for a 2D mesh, only minor modifications are necessary, and the code snippet is as follows:

```auto
import gmsh
import pygmsh
import meshio
import numpy
from dolfin import *
msh = meshio.read("mesh2d.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

line_mesh = create_mesh(msh, "line", prune_z=True)
meshio.write("mf.xdmf", line_mesh)

triangle_mesh = create_mesh(msh, "triangle", prune_z=True)
meshio.write("mesh.xdmf", triangle_mesh)

mesh = Mesh()
with XDMFFile("mesh.xdmf") as infile:
    infile.read(mesh)
mvc = MeshValueCollection("size_t", mesh, 1)

with XDMFFile("mf.xdmf") as infile:
    infile.read(mvc, "name_to_read")
mf = cpp.mesh.MeshFunctionSizet(mesh, mvc)
File("dolfinmesh.pvd").write(mesh)
File("dolfincellfunc.pvd").write(mf)

```

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