def init_mesh(self, n=4, meshtype='tri', h=0.1):
""" generate the initial mesh
"""
node = np.array([(0, 0), (1, 0), (1, 1), (0, 1)], dtype=np.float)
if meshtype is 'quadtree':
cell = np.array([(0, 1, 2, 3)], dtype=np.int)
mesh = Quadtree(node, cell)
mesh.uniform_refine(n)
return mesh
if meshtype is 'quad':
node = np.array([(0, 0), (1, 0), (1, 1), (0, 1), (0.5, 0),
(1, 0.4), (0.3, 1), (0, 0.6), (0.5, 0.45)],
dtype=np.float)
cell = np.array([(0, 4, 8, 7), (4, 1, 5, 8), (7, 8, 6, 3),
(8, 5, 2, 6)],
dtype=np.int)
mesh = QuadrangleMesh(node, cell)
mesh.uniform_refine(n)
return mesh
elif meshtype is 'tri':
cell = np.array([(1, 2, 0), (3, 0, 2)], dtype=np.int)
mesh = TriangleMesh(node, cell)
mesh.uniform_refine(n)
return mesh
elif meshtype is 'stri':
mesh = StructureQuadMesh([0, 1, 0, 1], h)
return mesh
else:
raise ValueError("".format)
def quadmesh(n=10, L=12):
box = [0, L, 0, L]
qmesh = StructureQuadMesh(box, n, n)
node = qmesh.node
cell = qmesh.ds.cell
quadtree = Quadtree(node, cell)
return quadtree
def init_mesh(self, n=4, meshtype='quadtree', h=0.1, nx=10, ny=10):
point = np.array([(-1, -1), (1, -1), (1, 1), (-1, 1)],
dtype=np.float64)
if meshtype == 'quadtree':
cell = np.array([(0, 1, 2, 3)], dtype=np.int_)
mesh = Quadtree(point, cell)
mesh.uniform_refine(n)
return mesh
elif meshtype == 'tri':
cell = np.array([(1, 2, 0), (3, 0, 2)], dtype=np.int_)
mesh = TriangleMesh(point, cell)
mesh.uniform_refine(n)
return mesh
elif meshtype == 'stri':
mesh = StructureQuadMesh([0, 1, 0, 1], nx, ny)
return mesh
else:
raise ValueError("".format)
def init_mesh(self, n=4, meshtype='tri', h=0.1):
""" generate the initial mesh
"""
node = np.array([(0, 0), (1, 0), (1, 1), (0, 1)], dtype=np.float64)
if meshtype == 'quadtree':
cell = np.array([(0, 1, 2, 3)], dtype=np.int_)
mesh = Quadtree(node, cell)
mesh.uniform_refine(n)
return mesh
elif meshtype == 'tri':
cell = np.array([(1, 2, 0), (3, 0, 2)], dtype=np.int_)
mesh = TriangleMesh(node, cell)
mesh.uniform_refine(n)
return mesh
elif meshtype == 'stri':
mesh = StructureQuadMesh([0, 1, 0, 1], h)
return mesh
else:
raise ValueError("".format)
def init_mesh(self, n=4, meshtype='tri', h=0.1):
""" generate the initial mesh
"""
node = np.array([(0, -1), (1, -1), (1, 1), (0, 1)], dtype=np.float64)
if meshtype == 'quadtree':
cell = np.array([(0, 1, 2, 3)], dtype=np.int_)
mesh = Quadtree(node, cell)
mesh.uniform_refine(n)
return mesh
if meshtype == 'quad':
node = np.array([(0, 0), (1, 0), (1, 1), (0, 1), (0.5, 0),
(1, 0.4), (0.3, 1), (0, 0.6), (0.5, 0.45)],
dtype=np.float64)
cell = np.array([(0, 4, 8, 7), (4, 1, 5, 8), (7, 8, 6, 3),
(8, 5, 2, 6)],
dtype=np.int_)
mesh = QuadrangleMesh(node, cell)
mesh.uniform_refine(n)
return mesh
elif meshtype == 'tri':
cell = np.array([(1, 2, 0), (3, 0, 2)], dtype=np.int_)
mesh = TriangleMesh(node, cell)
mesh.uniform_refine(n)
# |--- to test
box = [0, 1, -1, 1]
mesh = MF.boxmesh2d(box, nx=10, ny=20, meshtype='tri')
# |---
return mesh
elif meshtype == 'halfedge':
cell = np.array([(1, 2, 0), (3, 0, 2)], dtype=np.int_)
mesh = TriangleMesh(node, cell)
mesh = HalfEdgeMesh2d.from_mesh(mesh)
mesh.uniform_refine(n)
return mesh
elif meshtype == 'squad':
mesh = StructureQuadMesh([0, 1, 0, 1], h)
return mesh
else:
raise ValueError("".format)
import numpy as np
import matplotlib.pyplot as plt
import sys
from fealpy.mesh.StructureQuadMesh import StructureQuadMesh
box = [0, 1, 0, 1]
n = 8
qmesh = StructureQuadMesh(box, n, n)
cell2cell = qmesh.ds.cell_to_cell()
print('cell2cell',cell2cell)
NN = qmesh.number_of_nodes()
NE = qmesh.number_of_edges()
NC = qmesh.number_of_cells()
#a = cell2cell[:NC:n,0]
#print('a',a)
X = np.zeros(NE + NC, dtype=np.float)
I = np.arange(NC, dtype=np.int)
J = I
fig = plt.figure()
axes = fig.gca()
qmesh.add_plot(axes)
qmesh.find_node(axes, showindex=True)
qmesh.find_edge(axes, showindex=False)
qmesh.find_cell(axes, showindex=False)
plt.show()
return hg n = int(sys.argv[1]) nx = n ny = n box = [-2, 2, -2, 2] cxy = (0.0, 0.0) r = 1 interface0 = lambda p: dcircle(p, cxy, r) interface = lambda p: circle(p, cxy, r) mesh = StructureQuadMesh(box, nx, ny) dx = mesh.dx dy = mesh.dy point = mesh.point N = point.shape[0] phi = interface(point) phiSign = sign(phi) edge = mesh.ds.edge NE = edge.shape[0] isCutEdge = phiSign[edge[:, 0]]*phiSign[edge[:, 1]] < 0 A = point[edge[isCutEdge, 0]].copy() B = point[edge[isCutEdge, 1]].copy()
import numpy as np import matplotlib.pyplot as plt import sys from fealpy.mesh.StructureQuadMesh import StructureQuadMesh box = [0, 1, 0, 1] n = 2 qmesh = StructureQuadMesh(box, n, n) qmesh.print() fig = plt.figure() axes = fig.gca() qmesh.add_plot(axes) qmesh.find_point(axes, showindex=True) qmesh.find_edge(axes, showindex=True) qmesh.find_cell(axes, showindex=True) plt.show()
import numpy as np import matplotlib.pyplot as plt from fealpy.mesh.StructureQuadMesh import StructureQuadMesh L=20 box = [0, L, 0, L] qmesh = StructureQuadMesh(box, nx=2, ny=2) C = qmesh.ds.peoriod_matrix() print(C.toarray()) fig = plt.figure() axes = fig.gca() qmesh.add_plot(axes) qmesh.find_node(axes, showindex=True) plt.show()