Restiction on mesh

1

I want to compute the solution in a particular subdomain and I imported mesh from gmsh. please find attached fenics code and error.

import numpy as N
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

import meshio
msh = meshio.read("subbygmsh.msh")
triangle_mesh = create_mesh(msh, "triangle", True)
line_mesh = create_mesh(msh, "line", True)
meshio.write("mesh1.xdmf", triangle_mesh)
meshio.write("mf1.xdmf", line_mesh) 

from dolfin import*
mesh=Mesh()
mvc = MeshValueCollection("size_t", mesh, mesh.topology().dim())
with XDMFFile("mesh1.xdmf") as infile:
   infile.read(mesh)
   infile.read(mvc, "name_to_read")

cf = cpp.mesh.MeshFunctionSizet(mesh, mvc)

dx= Measure("dx", domain=mesh, subdomain_data=cf)

mvc = MeshValueCollection("size_t", mesh, mesh.topology().dim()-1)
with XDMFFile("mf1.xdmf") as infile:
    infile.read(mvc, "name_to_read")   
mf = cpp.mesh.MeshFunctionSizet(mesh, mvc)    
ds= Measure("ds", domain=mesh, subdomain_data=mf)

restiction=Restriction(mesh, 1)

and error is NameError: name ‘Restriction’ is not defined

2

As the error clearly states, Restriction is not defined in the dolfin package. Could you please clearify where you have gotten this function from. There is a function for creating “sub-meshes”, namely MeshView, as for instance used here: Bitbucket

1 Like
3

Thank you for your replay,

Here you can find the restriction function

https://fenicsproject.org/olddocs/dolfin/1.5.0/python/programmers-reference/cpp/mesh/Restriction.html

4

You are looking at a very outdated documentation, for FEniCS 1.5.0 [released 2015-01-12]

Latest C++ documentation can be found here: DOLFIN: Class Index

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