示例#1
0
import sys

import numpy as np

import matplotlib.pyplot as plt

from fealpy.mesh.TriangleMesh import TriangleMesh, TriangleMeshDataStructure

node = np.array([(0, 0), (1, 0), (1, 1), (0, 1)], dtype=np.float)
cell = np.array([(1, 2, 0), (3, 0, 2)], dtype=np.int)

tmesh = TriangleMesh(node, cell)
tmesh.uniform_refine(1)
node = tmesh.node
cell = tmesh.entity('cell')
print(tmesh.ds.node_to_cell())
N = node.shape[0]
tmeshstrcture = TriangleMeshDataStructure(N, cell)
fig = plt.figure()
axes = fig.gca()
tmesh.add_plot(axes)
tmesh.find_node(axes, showindex=True)
tmesh.find_edge(axes, showindex=True)
tmesh.find_cell(axes, showindex=True)
plt.show()
示例#2
0
    [1,1],
    [0,1]], dtype=np.float)
cell = np.array([[1, 2, 0], [3, 0, 2]], dtype=np.int)

mesh = TriangleMesh(point, cell)
V = LagrangeFiniteElementSpace(mesh, degree)

bc = np.array([(0.1, 0.2, 0.7), (0.3, 0.4, 0.3)])
for b in bc:
    print(V.basis(b))

#print(V.basis_einsum(bc))

ipoints = V.interpolation_points()
cell2dof = V.cell_to_dof()
fig, axes = plt.subplots(1, 3)
mesh.add_plot(axes[0])
mesh.find_node(axes[0], node=ipoints, showindex=True)

for ax in axes.reshape(-1)[1:]:
    ax.axis('tight')
    ax.axis('off')

axes[1].table(cellText=cell, rowLabels=['0:', '1:'], loc='center', fontsize=100)
axes[1].set_title('cell', y=0.7)
axes[2].table(cellText=cell2dof, rowLabels=['0:', '1:'], loc='center',
        fontsize=100)
axes[2].set_title('cell2dof', y=0.6)
plt.tight_layout(pad=1, w_pad=1, h_pad=1.0)
plt.show()
示例#3
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cell[:NC,2] = sign[0:-1,0:-1].flatten()
cell[NC:,0] = sign[1:,0:-1].flatten()#每个小正方形上面的小三角形
cell[NC:,1] = sign[0:-1,0:-1].flatten()
cell[NC:,2] = sign[1:,1:].flatten()
print(node)
print(cell)


# In[5]:


from fealpy.mesh.TriangleMesh import TriangleMesh
import matplotlib.pyplot as plt 
get_ipython().run_line_magic('matplotlib', 'inline')
tmesh = TriangleMesh(node, cell)
fig, axes = plt.subplots(1, 3,figsize=(15,15))
tmesh.add_plot(axes[0])
tmesh.find_node(axes[0], showindex=True, markersize=20, fontsize=20)
tmesh.find_cell(axes[0], showindex=True, markersize=15, fontsize=15)
axes[0].set_title('mesh')
for ax in axes.reshape(-1)[1:]:
    ax.axis('tight')
    ax.axis('off')
axes[1].table(cellText=node, rowLabels=np.arange(NN), loc='center')
axes[1].set_title('node', y=0.2)
axes[2].table(cellText=cell, rowLabels=np.arange(2*NC), loc='center')
axes[2].set_title('cell', y=0.9)
plt.tight_layout(pad=0.4, w_pad=1, h_pad=1.0)
plt.show()
示例#4
0
tmesh = TriangleMesh(point, cell)

# Partition the mesh cells into n parts
edgecuts, parts = metis.part_mesh(tmesh, nparts=n, entity='cell', contig=True)

node = tmesh.node
edge = tmesh.ds.edge
cell = tmesh.ds.cell
cell2edge = tmesh.ds.cell_to_edge()
edge2cell = tmesh.ds.edge_to_cell()
isBdNode = tmesh.ds.boundary_node_flag()

data = {
    'Point': node,
    'Face': edge + 1,
    'Elem': cell + 1,
    'Edge2Elem': edge2cell + 1,
    'isBdPoint': isBdNode,
    'Partitions': parts + 1
}

sio.matlab.savemat('test' + str(n) + 'parts' + str(h) + '.mat', data)

fig = plt.figure()
axes = fig.gca()
tmesh.add_plot(axes, cellcolor='w')
tmesh.find_node(axes, color=parts, markersize=20)
fig.savefig('test.pdf')
plt.show()