def createMesh(nb_segs_x, x_start=0, x_end=1., y_start=0., mesh_name="Mesh"):
mesh_dim = 2
nb_nodes = nb_segs_x + 1
dx = (x_end - x_start) / nb_segs_x
mesh = MC.MEDCouplingIMesh(mesh_name, mesh_dim, [nb_nodes, nb_nodes],
[x_start, y_start], [dx] * mesh_dim)
return mesh
def create2DGrid(xmin,
xmax,
nx,
ymin,
ymax,
ny,
mesh_name="Mesh_rectangle_with_rectangles"):
mesh_dim = 2
dx = (xmax - xmin) / nx
dy = (ymax - ymin) / ny
mesh = mc.MEDCouplingIMesh(mesh_name, mesh_dim, [nx + 1, ny + 1],
[xmin, ymin], [dx, dy])
return mesh
def create3DGrid(xmin,
xmax,
nx,
ymin,
ymax,
ny,
zmin,
zmax,
nz,
mesh_name="Mesh_cube_with_cuboids"):
mesh_dim = 3
dx = (xmax - xmin) / nx
dy = (ymax - ymin) / ny
dz = (zmax - zmin) / nz
mesh = mc.MEDCouplingIMesh(mesh_name, mesh_dim, [nx + 1, ny + 1, nz + 1],
[xmin, ymin, zmin], [dx, dy, dz])
return mesh
def mesh_rectangle_with_rectangles(xmin,
xmax,
nx,
ymin,
ymax,
ny,
mesh_name="Mesh_rectangle_with_rectangles"):
mesh_dim = 2
dx = (xmax - xmin) / nx
dy = (ymax - ymin) / ny
mesh = mc.MEDCouplingIMesh(mesh_name, mesh_dim, [nx + 1, ny + 1],
[xmin, ymin], [dx, dy]).buildUnstructured()
#--------------- Boundary groups -----------------#
# Crée les éléments 1D pour pouvoir imposer les conditions aux limites
mesh_1d = mesh.computeSkin()
# Identifie les segments de chaque côté pour créer les groupes
tol = 1e-10
barycenters = mesh_1d.computeIsoBarycenterOfNodesPerCell()
ids_left = []
ids_right = []
ids_bottom = []
ids_top = []
for i, coord in enumerate(barycenters):
x, y = coord
if abs(x - xmin) < tol:
ids_left.append(i)
elif abs(x - xmax) < tol:
ids_right.append(i)
elif abs(y - ymin) < tol:
ids_bottom.append(i)
elif abs(y - ymax) < tol:
ids_top.append(i)
else:
raise ValueError(
"Pb with boundary construction : barycenter does not belong to any border group"
)
arr_left = mc.DataArrayInt(ids_left)
arr_right = mc.DataArrayInt(ids_right)
arr_bottom = mc.DataArrayInt(ids_bottom)
arr_top = mc.DataArrayInt(ids_top)
arr_left.setName("Left")
arr_right.setName("Right")
arr_bottom.setName("Bottom")
arr_top.setName("Top")
# Trie les cellules par type conformément à la convention MED fichier
o2n = mesh.sortCellsInMEDFileFrmt()
meshMEDFile = ML.MEDFileUMesh.New()
# Ecrit le maillage 2D
meshMEDFile.setMeshAtLevel(0, mesh)
# Ecrit le maillage 1D
meshMEDFile.setMeshAtLevel(-1, mesh_1d)
# Ecrit les groupes
meshMEDFile.addGroup(-1, arr_left)
meshMEDFile.addGroup(-1, arr_right)
meshMEDFile.addGroup(-1, arr_bottom)
meshMEDFile.addGroup(-1, arr_top)
# Check that everything is coherent (will throw if not)
mesh.checkConsistencyLight()
filename = mesh_name + ".med"
# Write the result into a VTU file that can be read with ParaView
#mesh.writeVTK(mesh_name+".vtu")
# Write the result into a MED file that can be read with Salomé
meshMEDFile.write(filename, 2) # 2 stands for write from scratch