Hello FEniCS family,

Problem in generating a msh file (fenics 19):

File “/Users/mac/Projects/PCMFlow/Domain.py”, line 38, in channelMesh

lg = geometry.add_line_loop(lines)

AttributeError: ‘Geometry’ object has no attribute ‘add_line_loop’

See the following code :

#!/usr/bin/env python3

#
-*- coding: utf-8 -*-

“”"

Created on Thu Jun 1 11:32:51 2023

@author: mac

“”"

from dolfin import *

from fenics import *

import pygmsh

#from fipy import CellVariable, Gmsh2D

import pyvista

import meshio

inflow = 1

outflow = 2

walls = 3

obstacle = 4

x = 5

y = 0.5

c_x = 0.3

c_y = 0.4

r_x = 0.04

d = 0.2

def channelMesh(res=0.03):

lcar=res

llcar=5*res

with pygmsh.geo.Geometry() as geometry:

points = [geometry.add_point((0, 0, 0),lcar),

geometry.add_point((x, 0, 0),llcar),

geometry.add_point((x, y, 0),llcar),

geometry.add_point((0, y, 0),lcar)]

lines = [geometry.add_line(points[i], points[i+1])

for i in range(len(points)-1)]

lines.append(geometry.add_line(points[-1], points[0]))

lg = geometry.add_line_loop(lines)

sf = geometry.add_plane_surface(lg)

outflow_list = [lines[1]]

flow_list = [lines[-1]]

wall_list = [lines[0], lines[2]]

```
geometry.add_physical_surface(sf,label=12)
geometry.add_physical_line(flow_list, label=inflow)
geometry.add_physical_line(outflow_list, label=outflow)
geometry.add_physical_line(wall_list, label=walls)
(points, cells, point_data,
cell_data, field_data) = geometry.generate_mesh()
meshio.write("meshFile.xdmf", meshio.Mesh(
points=points, cells={"triangle": cells["triangle"]}))
meshio.write("MeshFile.xdmf", meshio.Mesh(
points=points, cells={"line": cells["line"]},
cell_data={"line": {"name_to_read":
cell_data["line"]["gmsh:physical"]}}))
```

if **name**==“**main**”:

```
channelMesh(0.03)
```

Any help is greatly appreciated!