Files
simpeg/SimPEG/Mesh/LogicallyRectMesh.py
T
2014-03-03 15:50:06 -08:00

444 lines
19 KiB
Python

from SimPEG import Utils, np
from BaseMesh import BaseRectangularMesh
from DiffOperators import DiffOperators
from InnerProducts import InnerProducts
# Some helper functions.
length2D = lambda x: (x[:, 0]**2 + x[:, 1]**2)**0.5
length3D = lambda x: (x[:, 0]**2 + x[:, 1]**2 + x[:, 2]**2)**0.5
normalize2D = lambda x: x/np.kron(np.ones((1, 2)), Utils.mkvc(length2D(x), 2))
normalize3D = lambda x: x/np.kron(np.ones((1, 3)), Utils.mkvc(length3D(x), 2))
class LogicallyRectMesh(BaseRectangularMesh, DiffOperators, InnerProducts):
"""
LogicallyRectMesh is a mesh class that deals with logically rectangular meshes.
Example of a logically rectangular mesh:
.. plot::
:include-source:
from SimPEG import Mesh, Utils
X, Y = Utils.exampleLrmGrid([3,3],'rotate')
M = Mesh.LogicallyRectMesh([X, Y])
M.plotGrid(showIt=True)
"""
__metaclass__ = Utils.SimPEGMetaClass
_meshType = 'LRM'
def __init__(self, nodes):
assert type(nodes) == list, "'nodes' variable must be a list of np.ndarray"
assert len(nodes) > 1, "len(node) must be greater than 1"
for i, nodes_i in enumerate(nodes):
assert type(nodes_i) == np.ndarray, ("nodes[%i] is not a numpy array." % i)
assert nodes_i.shape == nodes[0].shape, ("nodes[%i] is not the same shape as nodes[0]" % i)
assert len(nodes[0].shape) == len(nodes), "Dimension mismatch"
assert len(nodes[0].shape) > 1, "Not worth using LRM for a 1D mesh."
BaseRectangularMesh.__init__(self, np.array(nodes[0].shape)-1, None)
# Save nodes to private variable _gridN as vectors
self._gridN = np.ones((nodes[0].size, self.dim))
for i, node_i in enumerate(nodes):
self._gridN[:, i] = Utils.mkvc(node_i.astype(float))
def gridCC():
doc = "Cell-centered grid."
def fget(self):
if self._gridCC is None:
self._gridCC = np.concatenate([self.aveN2CC*self.gridN[:,i] for i in range(self.dim)]).reshape((-1,self.dim), order='F')
return self._gridCC
return locals()
_gridCC = None # Store grid by default
gridCC = property(**gridCC())
def gridN():
doc = "Nodal grid."
def fget(self):
if self._gridN is None:
raise Exception("Someone deleted this. I blame you.")
return self._gridN
return locals()
_gridN = None # Store grid by default
gridN = property(**gridN())
def gridFx():
doc = "Face staggered grid in the x direction."
def fget(self):
if self._gridFx is None:
N = self.r(self.gridN, 'N', 'N', 'M')
if self.dim == 2:
XY = [Utils.mkvc(0.5 * (n[:, :-1] + n[:, 1:])) for n in N]
self._gridFx = np.c_[XY[0], XY[1]]
elif self.dim == 3:
XYZ = [Utils.mkvc(0.25 * (n[:, :-1, :-1] + n[:, :-1, 1:] + n[:, 1:, :-1] + n[:, 1:, 1:])) for n in N]
self._gridFx = np.c_[XYZ[0], XYZ[1], XYZ[2]]
return self._gridFx
return locals()
_gridFx = None # Store grid by default
gridFx = property(**gridFx())
def gridFy():
doc = "Face staggered grid in the y direction."
def fget(self):
if self._gridFy is None:
N = self.r(self.gridN, 'N', 'N', 'M')
if self.dim == 2:
XY = [Utils.mkvc(0.5 * (n[:-1, :] + n[1:, :])) for n in N]
self._gridFy = np.c_[XY[0], XY[1]]
elif self.dim == 3:
XYZ = [Utils.mkvc(0.25 * (n[:-1, :, :-1] + n[:-1, :, 1:] + n[1:, :, :-1] + n[1:, :, 1:])) for n in N]
self._gridFy = np.c_[XYZ[0], XYZ[1], XYZ[2]]
return self._gridFy
return locals()
_gridFy = None # Store grid by default
gridFy = property(**gridFy())
def gridFz():
doc = "Face staggered grid in the z direction."
def fget(self):
if self._gridFz is None and self.dim == 3:
N = self.r(self.gridN, 'N', 'N', 'M')
XYZ = [Utils.mkvc(0.25 * (n[:-1, :-1, :] + n[:-1, 1:, :] + n[1:, :-1, :] + n[1:, 1:, :])) for n in N]
self._gridFz = np.c_[XYZ[0], XYZ[1], XYZ[2]]
return self._gridFz
return locals()
_gridFz = None # Store grid by default
gridFz = property(**gridFz())
def gridEx():
doc = "Edge staggered grid in the x direction."
def fget(self):
if self._gridEx is None:
N = self.r(self.gridN, 'N', 'N', 'M')
if self.dim == 2:
XY = [Utils.mkvc(0.5 * (n[:-1, :] + n[1:, :])) for n in N]
self._gridEx = np.c_[XY[0], XY[1]]
elif self.dim == 3:
XYZ = [Utils.mkvc(0.5 * (n[:-1, :, :] + n[1:, :, :])) for n in N]
self._gridEx = np.c_[XYZ[0], XYZ[1], XYZ[2]]
return self._gridEx
return locals()
_gridEx = None # Store grid by default
gridEx = property(**gridEx())
def gridEy():
doc = "Edge staggered grid in the y direction."
def fget(self):
if self._gridEy is None:
N = self.r(self.gridN, 'N', 'N', 'M')
if self.dim == 2:
XY = [Utils.mkvc(0.5 * (n[:, :-1] + n[:, 1:])) for n in N]
self._gridEy = np.c_[XY[0], XY[1]]
elif self.dim == 3:
XYZ = [Utils.mkvc(0.5 * (n[:, :-1, :] + n[:, 1:, :])) for n in N]
self._gridEy = np.c_[XYZ[0], XYZ[1], XYZ[2]]
return self._gridEy
return locals()
_gridEy = None # Store grid by default
gridEy = property(**gridEy())
def gridEz():
doc = "Edge staggered grid in the z direction."
def fget(self):
if self._gridEz is None and self.dim == 3:
N = self.r(self.gridN, 'N', 'N', 'M')
XYZ = [Utils.mkvc(0.5 * (n[:, :, :-1] + n[:, :, 1:])) for n in N]
self._gridEz = np.c_[XYZ[0], XYZ[1], XYZ[2]]
return self._gridEz
return locals()
_gridEz = None # Store grid by default
gridEz = property(**gridEz())
# --------------- Geometries ---------------------
#
#
# ------------------- 2D -------------------------
#
# node(i,j) node(i,j+1)
# A -------------- B
# | |
# | cell(i,j) |
# | I |
# | |
# D -------------- C
# node(i+1,j) node(i+1,j+1)
#
# ------------------- 3D -------------------------
#
#
# node(i,j,k+1) node(i,j+1,k+1)
# E --------------- F
# /| / |
# / | / |
# / | / |
# node(i,j,k) node(i,j+1,k)
# A -------------- B |
# | H ----------|---- G
# | /cell(i,j) | /
# | / I | /
# | / | /
# D -------------- C
# node(i+1,j,k) node(i+1,j+1,k)
def vol():
doc = "Construct cell volumes of the 3D model as 1d array."
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
return locals()
_vol = None
vol = property(**vol())
def area():
doc = "Face areas."
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
return locals()
_area = None
area = property(**area())
def normals():
doc = """Face normals: calling this will average
the computed normals so that there is one
per face. This is especially relevant in
3D, as there are up to 4 different normals
for each face that will be different.
To reshape the normals into a matrix and get the y component::
NyX, NyY, NyZ = M.r(M.normals, 'F', 'Fy', 'M')
"""
def fget(self):
if(self._normals is None):
self.area # calling .area will create the face normals
if self.dim == 2:
return normalize2D(np.r_[self._normals[0], self._normals[1]])
elif self.dim == 3:
normal1 = (self._normals[0][0] + self._normals[0][1] + self._normals[0][2] + self._normals[0][3])/4
normal2 = (self._normals[1][0] + self._normals[1][1] + self._normals[1][2] + self._normals[1][3])/4
normal3 = (self._normals[2][0] + self._normals[2][1] + self._normals[2][2] + self._normals[2][3])/4
return normalize3D(np.r_[normal1, normal2, normal3])
return locals()
_normals = None
normals = property(**normals())
def edge():
doc = "Edge legnths."
def fget(self):
if(self._edge is None or self._tangents is None):
if(self.dim == 2):
xy = self.gridN
A, D = Utils.indexCube('AD', self.vnC+1, np.array([self.nCx, self.nNy]))
edge1 = xy[D, :] - xy[A, :]
A, B = Utils.indexCube('AB', self.vnC+1, np.array([self.nNx, self.nCy]))
edge2 = xy[B, :] - xy[A, :]
self._edge = np.r_[Utils.mkvc(length2D(edge1)), Utils.mkvc(length2D(edge2))]
self._tangents = np.r_[edge1, edge2]/np.c_[self._edge, self._edge]
elif(self.dim == 3):
xyz = self.gridN
A, D = Utils.indexCube('AD', self.vnC+1, np.array([self.nCx, self.nNy, self.nNz]))
edge1 = xyz[D, :] - xyz[A, :]
A, B = Utils.indexCube('AB', self.vnC+1, np.array([self.nNx, self.nCy, self.nNz]))
edge2 = xyz[B, :] - xyz[A, :]
A, E = Utils.indexCube('AE', self.vnC+1, np.array([self.nNx, self.nNy, self.nCz]))
edge3 = xyz[E, :] - xyz[A, :]
self._edge = np.r_[Utils.mkvc(length3D(edge1)), Utils.mkvc(length3D(edge2)), Utils.mkvc(length3D(edge3))]
self._tangents = np.r_[edge1, edge2, edge3]/np.c_[self._edge, self._edge, self._edge]
return self._edge
return locals()
_edge = None
edge = property(**edge())
def tangents():
doc = "Edge tangents."
def fget(self):
if(self._tangents is None):
self.edge # calling .edge will create the tangents
return self._tangents
return locals()
_tangents = None
tangents = property(**tangents())
#############################################
# Plotting Functions #
#############################################
def plotGrid(self, ax=None, nodes=False, faces=False, centers=False, edges=False, lines=True, showIt=False):
"""Plot the nodal, cell-centered and staggered grids for 1,2 and 3 dimensions.
.. plot::
:include-source:
from SimPEG import Mesh, Utils
X, Y = Utils.exampleLrmGrid([3,3],'rotate')
M = Mesh.LogicallyRectMesh([X, Y])
M.plotGrid(showIt=True)
"""
import matplotlib.pyplot as plt
import matplotlib
from mpl_toolkits.mplot3d import Axes3D
mkvc = Utils.mkvc
axOpts = {'projection':'3d'} if self.dim == 3 else {}
if ax is None: ax = plt.subplot(111, **axOpts)
NN = self.r(self.gridN, 'N', 'N', 'M')
if self.dim == 2:
if lines:
X1 = np.c_[mkvc(NN[0][:-1, :]), mkvc(NN[0][1:, :]), mkvc(NN[0][:-1, :])*np.nan].flatten()
Y1 = np.c_[mkvc(NN[1][:-1, :]), mkvc(NN[1][1:, :]), mkvc(NN[1][:-1, :])*np.nan].flatten()
X2 = np.c_[mkvc(NN[0][:, :-1]), mkvc(NN[0][:, 1:]), mkvc(NN[0][:, :-1])*np.nan].flatten()
Y2 = np.c_[mkvc(NN[1][:, :-1]), mkvc(NN[1][:, 1:]), mkvc(NN[1][:, :-1])*np.nan].flatten()
X = np.r_[X1, X2]
Y = np.r_[Y1, Y2]
ax.plot(X, Y, 'b-')
if centers:
ax.plot(self.gridCC[:,0],self.gridCC[:,1],'ro')
# Nx = self.r(self.normals, 'F', 'Fx', 'V')
# Ny = self.r(self.normals, 'F', 'Fy', 'V')
# Tx = self.r(self.tangents, 'E', 'Ex', 'V')
# Ty = self.r(self.tangents, 'E', 'Ey', 'V')
# ax.plot(self.gridN[:, 0], self.gridN[:, 1], 'bo')
# nX = np.c_[self.gridFx[:, 0], self.gridFx[:, 0] + Nx[0]*length, self.gridFx[:, 0]*np.nan].flatten()
# nY = np.c_[self.gridFx[:, 1], self.gridFx[:, 1] + Nx[1]*length, self.gridFx[:, 1]*np.nan].flatten()
# ax.plot(self.gridFx[:, 0], self.gridFx[:, 1], 'rs')
# ax.plot(nX, nY, 'r-')
# nX = np.c_[self.gridFy[:, 0], self.gridFy[:, 0] + Ny[0]*length, self.gridFy[:, 0]*np.nan].flatten()
# nY = np.c_[self.gridFy[:, 1], self.gridFy[:, 1] + Ny[1]*length, self.gridFy[:, 1]*np.nan].flatten()
# #ax.plot(self.gridFy[:, 0], self.gridFy[:, 1], 'gs')
# ax.plot(nX, nY, 'g-')
# tX = np.c_[self.gridEx[:, 0], self.gridEx[:, 0] + Tx[0]*length, self.gridEx[:, 0]*np.nan].flatten()
# tY = np.c_[self.gridEx[:, 1], self.gridEx[:, 1] + Tx[1]*length, self.gridEx[:, 1]*np.nan].flatten()
# ax.plot(self.gridEx[:, 0], self.gridEx[:, 1], 'r^')
# ax.plot(tX, tY, 'r-')
# nX = np.c_[self.gridEy[:, 0], self.gridEy[:, 0] + Ty[0]*length, self.gridEy[:, 0]*np.nan].flatten()
# nY = np.c_[self.gridEy[:, 1], self.gridEy[:, 1] + Ty[1]*length, self.gridEy[:, 1]*np.nan].flatten()
# #ax.plot(self.gridEy[:, 0], self.gridEy[:, 1], 'g^')
# ax.plot(nX, nY, 'g-')
elif self.dim == 3:
X1 = np.c_[mkvc(NN[0][:-1, :, :]), mkvc(NN[0][1:, :, :]), mkvc(NN[0][:-1, :, :])*np.nan].flatten()
Y1 = np.c_[mkvc(NN[1][:-1, :, :]), mkvc(NN[1][1:, :, :]), mkvc(NN[1][:-1, :, :])*np.nan].flatten()
Z1 = np.c_[mkvc(NN[2][:-1, :, :]), mkvc(NN[2][1:, :, :]), mkvc(NN[2][:-1, :, :])*np.nan].flatten()
X2 = np.c_[mkvc(NN[0][:, :-1, :]), mkvc(NN[0][:, 1:, :]), mkvc(NN[0][:, :-1, :])*np.nan].flatten()
Y2 = np.c_[mkvc(NN[1][:, :-1, :]), mkvc(NN[1][:, 1:, :]), mkvc(NN[1][:, :-1, :])*np.nan].flatten()
Z2 = np.c_[mkvc(NN[2][:, :-1, :]), mkvc(NN[2][:, 1:, :]), mkvc(NN[2][:, :-1, :])*np.nan].flatten()
X3 = np.c_[mkvc(NN[0][:, :, :-1]), mkvc(NN[0][:, :, 1:]), mkvc(NN[0][:, :, :-1])*np.nan].flatten()
Y3 = np.c_[mkvc(NN[1][:, :, :-1]), mkvc(NN[1][:, :, 1:]), mkvc(NN[1][:, :, :-1])*np.nan].flatten()
Z3 = np.c_[mkvc(NN[2][:, :, :-1]), mkvc(NN[2][:, :, 1:]), mkvc(NN[2][:, :, :-1])*np.nan].flatten()
X = np.r_[X1, X2, X3]
Y = np.r_[Y1, Y2, Y3]
Z = np.r_[Z1, Z2, Z3]
ax.plot(X, Y, 'b', zs=Z)
ax.set_zlabel('x3')
ax.grid(True)
ax.set_xlabel('x1')
ax.set_ylabel('x2')
if showIt: plt.show()
if __name__ == '__main__':
nc = 5
h1 = np.cumsum(np.r_[0, np.ones(nc)/(nc)])
nc = 7
h2 = np.cumsum(np.r_[0, np.ones(nc)/(nc)])
h3 = np.cumsum(np.r_[0, np.ones(nc)/(nc)])
dee3 = True
if dee3:
X, Y, Z = Utils.ndgrid(h1, h2, h3, vector=False)
M = LogicallyRectMesh([X, Y, Z])
else:
X, Y = Utils.ndgrid(h1, h2, vector=False)
M = LogicallyRectMesh([X, Y])
print M.r(M.normals, 'F', 'Fx', 'V')