def fget(self): if(self._area is None or self._normals is None): # Compute areas of cell faces if(self.dim == 2): xy = self.gridN A, B = Utils.indexCube('AB', self.vnC+1, np.array([self.nNx, self.nCy])) edge1 = xy[B, :] - xy[A, :] normal1 = np.c_[edge1[:, 1], -edge1[:, 0]] area1 = length2D(edge1) A, D = Utils.indexCube('AD', self.vnC+1, np.array([self.nCx, self.nNy])) # Note that we are doing A-D to make sure the normal points the right way. # Think about it. Look at the picture. Normal points towards C iff you do this. edge2 = xy[A, :] - xy[D, :] normal2 = np.c_[edge2[:, 1], -edge2[:, 0]] area2 = length2D(edge2) self._area = np.r_[Utils.mkvc(area1), Utils.mkvc(area2)] self._normals = [normalize2D(normal1), normalize2D(normal2)] elif(self.dim == 3): A, E, F, B = Utils.indexCube('AEFB', self.vnC+1, np.array([self.nNx, self.nCy, self.nCz])) normal1, area1 = Utils.faceInfo(self.gridN, A, E, F, B, average=False, normalizeNormals=False) A, D, H, E = Utils.indexCube('ADHE', self.vnC+1, np.array([self.nCx, self.nNy, self.nCz])) normal2, area2 = Utils.faceInfo(self.gridN, A, D, H, E, average=False, normalizeNormals=False) A, B, C, D = Utils.indexCube('ABCD', self.vnC+1, np.array([self.nCx, self.nCy, self.nNz])) normal3, area3 = Utils.faceInfo(self.gridN, A, B, C, D, average=False, normalizeNormals=False) self._area = np.r_[Utils.mkvc(area1), Utils.mkvc(area2), Utils.mkvc(area3)] self._normals = [normal1, normal2, normal3] return self._area
def vol(self): """ Construct cell volumes of the 3D model as 1d array """ if getattr(self, '_vol', None) is None: if self.dim == 2: A, B, C, D = Utils.indexCube('ABCD', self.vnC+1) normal, area = Utils.faceInfo(np.c_[self.gridN, np.zeros( (self.nN, 1))], A, B, C, D) self._vol = area elif self.dim == 3: # Each polyhedron can be decomposed into 5 tetrahedrons # However, this presents a choice so we may as well divide in # two ways and average. A, B, C, D, E, F, G, H = Utils.indexCube('ABCDEFGH', self.vnC + 1) vol1 = (Utils.volTetra(self.gridN, A, B, D, E) + # cutted edge top Utils.volTetra(self.gridN, B, E, F, G) + # cutted edge top Utils.volTetra(self.gridN, B, D, E, G) + # middle Utils.volTetra(self.gridN, B, C, D, G) + # cutted edge bottom Utils.volTetra(self.gridN, D, E, G, H)) # cutted edge bottom vol2 = (Utils.volTetra(self.gridN, A, F, B, C) + # cutted edge top Utils.volTetra(self.gridN, A, E, F, H) + # cutted edge top Utils.volTetra(self.gridN, A, H, F, C) + # middle Utils.volTetra(self.gridN, C, H, D, A) + # cutted edge bottom Utils.volTetra(self.gridN, C, G, H, F)) # cutted edge bottom self._vol = (vol1 + vol2)/2 return self._vol
def fget(self): if(self._vol is None): if self.dim == 2: A, B, C, D = Utils.indexCube('ABCD', self.vnC+1) normal, area = Utils.faceInfo(np.c_[self.gridN, np.zeros((self.nN, 1))], A, B, C, D) self._vol = area elif self.dim == 3: # Each polyhedron can be decomposed into 5 tetrahedrons # However, this presents a choice so we may as well divide in two ways and average. A, B, C, D, E, F, G, H = Utils.indexCube('ABCDEFGH', self.vnC+1) vol1 = (Utils.volTetra(self.gridN, A, B, D, E) + # cutted edge top Utils.volTetra(self.gridN, B, E, F, G) + # cutted edge top Utils.volTetra(self.gridN, B, D, E, G) + # middle Utils.volTetra(self.gridN, B, C, D, G) + # cutted edge bottom Utils.volTetra(self.gridN, D, E, G, H)) # cutted edge bottom vol2 = (Utils.volTetra(self.gridN, A, F, B, C) + # cutted edge top Utils.volTetra(self.gridN, A, E, F, H) + # cutted edge top Utils.volTetra(self.gridN, A, H, F, C) + # middle Utils.volTetra(self.gridN, C, H, D, A) + # cutted edge bottom Utils.volTetra(self.gridN, C, G, H, F)) # cutted edge bottom self._vol = (vol1 + vol2)/2 return self._vol