def setupERTPDE(domain, tolerance=1e-8, poisson=True, debug=0):
"""
used to setup all PDEs fro ERT related inversion. If available TRILINOS is usered.
:param domain: domain of the PDE
:type domain: `esys.escript.AbstractDomain`
:param tolerance: solver tolerance
:type tolerance: `float`
:param poisson: if True TRILINOS settings fro Poisson problems is set.
:type poisson: `bool`
:return: linear, scalar PDE with real coefficients.
:rtype: `esys.escript.linearPDEs.LinearPDE`
"""
pde = LinearSinglePDE(domain, isComplex=False)
pde.setSymmetryOn()
optionsG = pde.getSolverOptions()
optionsG.setSolverMethod(SolverOptions.PCG)
optionsG.setTolerance(tolerance)
if hasFeature('trilinos'):
if debug and getMPIRankWorld() == 0:
print("TRILINOS solver used.")
optionsG.setPackage(SolverOptions.TRILINOS)
optionsG.setPreconditioner(SolverOptions.AMG)
if poisson:
optionsG.setTrilinosParameter("problem:type", "Poisson-3D")
optionsG.setTrilinosParameter("verbosity", "none")
optionsG.setTrilinosParameter("number of equations", 1)
optionsG.setTrilinosParameter("problem: symmetric", True)
return pde
def setupERTPDE(domain, poisson=True):
"""
used t setup all ERT PDEs
"""
pde = LinearSinglePDE(domain, isComplex=False)
pde.setSymmetryOn()
optionsG = pde.getSolverOptions()
#optionsG.setSolverMethod(SolverOptions.DIRECT)
optionsG.setSolverMethod(SolverOptions.PCG)
optionsG.setTolerance(1e-8)
if True and hasFeature('trilinos'):
#print("trilinos solver used.")
optionsG.setPackage(SolverOptions.TRILINOS)
optionsG.setPreconditioner(SolverOptions.AMG)
if poisson:
optionsG.setTrilinosParameter("problem:type", "Poisson-3D")
optionsG.setTrilinosParameter("verbosity", "none")
optionsG.setTrilinosParameter("number of equations", 1)
#optionsG.setTrilinosParameter("max levels", 3) # 10 is default 3 seems to be a good number
#optionsG.setTrilinosParameter("cycle type", "V")
optionsG.setTrilinosParameter("problem: symmetric", True)
#optionsG.setTrilinosParameter("smoother: pre or post", "both")
#optionsG.setTrilinosParameter("Convergence Tolerance", 1e-12)
return pde
def __createPDE(self, airLayer=None):
pde = LinearSinglePDE(
self.domain,
isComplex=True,
)
optionsG = pde.getSolverOptions()
optionsG.setSolverMethod(SolverOptions.DIRECT)
pde.setSymmetryOn()
if self.useFastSolver and hasFeature('trilinos'): # ignored for now!
optionsG.setPackage(SolverOptions.TRILINOS)
optionsG.setPreconditioner(SolverOptions.AMG)
optionsG.setTrilinosParameter("problem: symmetric", True)
z = self.domain.getX()[self.domain.getDim() - 1]
b = inf(z)
if airLayer is None:
self.airLayer = whereNonNegative(z - sup(z))
elif isinstance(airLayer, float) or isinstance(airLayer, int):
self.airLayer = whereNonNegative(z - airLayer)
else:
self.airLayer = wherePositive(
interpolate(airLayer, Solution(self.domain)))
if self.fixBottom:
pde.setValue(q=self.airLayer + whereZero(z - b), r=self.airLayer)
else:
pde.setValue(q=self.airLayer, r=self.airLayer)
return pde
def __init__(self, domain, w, data, coordinates=None,
fixPotentialAtBottom=False,
tol=1e-8):
"""
initializes a new forward model with potential.
:param domain: domain of the model
:type domain: `Domain`
:param w: data weighting factors
:type w: ``Vector`` or list of ``Vector``
:param data: data
:type data: ``Vector`` or list of ``Vector``
:param coordinates: defines coordinate system to be used
:type coordinates: `ReferenceSystem` or `SpatialCoordinateTransformation`
:param fixPotentialAtBottom: if true potential is fixed to zero at the bottom of the domain
in addition to the top.
:type fixPotentialAtBottom: ``bool``
:param tol: tolerance of underlying PDE
:type tol: positive ``float``
"""
super(ForwardModelWithPotential, self).__init__()
self.__domain = domain
self.__trafo = makeTransformation(domain, coordinates)
try:
n=len(w)
m=len(data)
if not m == n:
raise ValueError("Length of weight and data must be the same.")
self.__weight = w
self.__data = data
except TypeError:
self.__weight = [w]
self.__data = [data]
BX = boundingBox(domain)
DIM = domain.getDim()
x = domain.getX()
self.__pde=LinearSinglePDE(domain)
self.__pde.getSolverOptions().setTolerance(tol)
self.__pde.setSymmetryOn()
z=x[DIM-1]
q0=whereZero(z-BX[DIM-1][1])
if fixPotentialAtBottom: q0+=whereZero(z-BX[DIM-1][0])
self.__pde.setValue(q=q0)
self.edge_lengths=np.asarray(boundingBoxEdgeLengths(domain))
self.diameter=1./sqrt(sum(1./self.edge_lengths**2))
self.__origweight=[]
for s in range(len(self.__weight)):
# save a copy of the original weights in case of rescaling
self.__origweight.append(1.*self.__weight[s])
if not self.__trafo.isCartesian():
fd=1./self.__trafo.getScalingFactors()
fw=self.__trafo.getScalingFactors()*sqrt(self.__trafo.getVolumeFactor())
for s in range(len(self.__weight)):
self.__weight[s] = fw * self.__weight[s]
self.__data[s] = fd * self.__data[s]
def test_complex_params_Brick(self):
domain=Brick(order=2,n0=10,n1=10,n2=10)
pde = LinearSinglePDE(domain, isComplex=True)
pde.setValue(D=1j)
pde.setValue(Y=1.0)
self.assertTrue(Lsup(pde.getSolution())==1.0, "Failed test_complex_params_Brick")
del domain
def __init__(self,
domain,
p0=0.,
level0=0,
gravity0=-9.81 * U.m * U.sec**(-2),
background_density=2670 * U.kg * U.m**(-3),
gravity_constant=U.Gravitational_Constant,
coordinates=None,
tol=1e-8):
"""
:param domain: domain of the model
:type domain: `Domain`
:param p0: pressure at level0
:type p0: scalar `Data` or ``float``
:param background_density: defines background_density in kg/m^3
:type background_density: ``float``
:param coordinates: defines coordinate system to be used
:type coordinates: ReferenceSystem` or `SpatialCoordinateTransformation`
:param tol: tolerance of underlying PDE
:type tol: positive ``float``
:param level0: pressure for z>=`level0` is set to zero.
:type level0: ``float``
:param gravity0: vertical background gravity at `level0`
:type gravity0: ``float``
"""
DIM = domain.getDim()
self.__domain = domain
self.__trafo = makeTransformation(domain, coordinates)
self.__pde = LinearSinglePDE(domain)
self.__pde.getSolverOptions().setTolerance(tol)
self.__pde.setSymmetryOn()
z = domain.getX()[DIM - 1]
self.__pde.setValue(q=whereNonNegative(z - level0), r=p0)
fw = self.__trafo.getScalingFactors(
)**2 * self.__trafo.getVolumeFactor()
A = self.__pde.createCoefficient("A")
for i in range(DIM):
A[i, i] = fw[i]
self.__pde.setValue(A=A)
z = Function(domain).getX()[DIM - 1]
self.__g_b = 4 * PI * gravity_constant / self.__trafo.getScalingFactors(
)[DIM - 1] * background_density * (level0 - z) + gravity0
self.__rho_b = background_density
def __createPDE(self):
"""
Create the PDE and set boundary conditions.
"""
pde = LinearSinglePDE(self.domain, isComplex=False)
domdim = self.domain.getDim()
zdim = domdim - 1
optionsG = pde.getSolverOptions()
optionsG.setSolverMethod(SolverOptions.PCG)
pde.setSymmetryOn()
pde.setValue(A=kronecker(domdim))
x = self.domain.getX()
q = whereZero(x[zdim] - sup(x[zdim]))
if self.fixBase:
q += whereZero(x[zdim] - inf(x[zdim]))
pde.setValue(q=q)
if hasFeature('trilinos'):
optionsG.setPackage(SolverOptions.TRILINOS)
optionsG.setPreconditioner(SolverOptions.AMG)
return pde
def __init__(self, domain, v_p, wavelet, source_tag, dt=None, p0=None, p0_t=None, absorption_zone=300*U.m, absorption_cut=1e-2, lumping=True):
"""
initialize the sonic wave solver
:param domain: domain of the problem
:type domain: `Domain`
:param v_p: p-velocity field
:type v_p: `Scalar`
:param wavelet: wavelet to describe the time evolution of source term
:type wavelet: `Wavelet`
:param source_tag: tag of the source location
:type source_tag: 'str' or 'int'
:param dt: time step size. If not present a suitable time step size is calculated.
:param p0: initial solution. If not present zero is used.
:param p0_t: initial solution change rate. If not present zero is used.
:param absorption_zone: thickness of absorption zone
:param absorption_cut: boundary value of absorption decay factor
:param lumping: if True mass matrix lumping is being used. This is accelerates the computing but introduces some diffusion.
"""
f=createAbsorptionLayerFunction(Function(domain).getX(), absorption_zone, absorption_cut)
v_p=v_p*f
if p0 == None:
p0=Scalar(0.,Solution(domain))
else:
p0=interpolate(p0, Solution(domain ))
if p0_t == None:
p0_t=Scalar(0.,Solution(domain))
else:
p0_t=interpolate(p0_t, Solution(domain ))
if dt == None:
dt=min(inf((1./5.)*domain.getSize()/v_p), wavelet.getTimeScale())
super(SonicWave, self).__init__( dt, u0=p0, v0=p0_t, t0=0.)
self.__wavelet=wavelet
self.__mypde=LinearSinglePDE(domain)
if lumping: self.__mypde.getSolverOptions().setSolverMethod(SolverOptions.HRZ_LUMPING)
self.__mypde.setSymmetryOn()
self.__mypde.setValue(D=1./v_p**2)
self.__source_tag=source_tag
self.__r=Scalar(0., DiracDeltaFunctions(self.__mypde.getDomain()))
def __init__(self, domain, p0=0., level0=0, gravity0=-9.81*U.m*U.sec**(-2),
background_density=2670* U.kg*U.m**(-3),
gravity_constant=U.Gravitational_Constant,
coordinates=None, tol=1e-8):
"""
:param domain: domain of the model
:type domain: `Domain`
:param p0: pressure at level0
:type p0: scalar `Data` or ``float``
:param background_density: defines background_density in kg/m^3
:type background_density: ``float``
:param coordinates: defines coordinate system to be used
:type coordinates: ReferenceSystem` or `SpatialCoordinateTransformation`
:param tol: tolerance of underlying PDE
:type tol: positive ``float``
:param level0: pressure for z>=`level0` is set to zero.
:type level0: ``float``
:param gravity0: vertical background gravity at `level0`
:type gravity0: ``float``
"""
DIM=domain.getDim()
self.__domain = domain
self.__trafo=makeTransformation(domain, coordinates)
self.__pde=LinearSinglePDE(domain)
self.__pde.getSolverOptions().setTolerance(tol)
self.__pde.setSymmetryOn()
z = domain.getX()[DIM-1]
self.__pde.setValue(q=whereNonNegative(z-level0), r=p0)
fw = self.__trafo.getScalingFactors()**2 * self.__trafo.getVolumeFactor()
A=self.__pde.createCoefficient("A")
for i in range(DIM): A[i,i]=fw[i]
self.__pde.setValue(A=A)
z = Function(domain).getX()[DIM-1]
self.__g_b= 4*PI*gravity_constant/self.__trafo.getScalingFactors()[DIM-1]*background_density*(level0-z) + gravity0
self.__rho_b=background_density
def __createPDE(self):
"""
Create the PDE and set boundary conditions.
"""
pde = LinearSinglePDE(self.domain, isComplex=False)
optionsG = pde.getSolverOptions()
optionsG.setSolverMethod(SolverOptions.PCG)
pde.setSymmetryOn()
pde.setValue(A=kronecker(self.domain.getDim()))
x = self.domain.getX()
pde.setValue(A=kronecker(self.domain))
if self.fixVert:
pde.setValue(
q=whereZero(x[0] - inf(x[0])) + whereZero(x[0] - sup(x[0])) +
whereZero(x[1] - inf(x[1])) + whereZero(x[1] - sup(x[1])))
elif self.fixBase:
pde.setValue(q=whereZero(x[2] - inf(x[2])))
else:
pde.setValue(q=whereZero(x[0] - inf(x[0])) *
whereZero(x[1] - inf(x[1])) *
whereZero(x[2] - inf(x[2])))
if hasFeature('trilinos'):
optionsG.setPackage(SolverOptions.TRILINOS)
optionsG.setPreconditioner(SolverOptions.AMG)
return pde
def runValetAcceleration(order):
domain=finley.Rectangle(100,10,order)
x=domain.getX()
# test Velet scheme
dt=inf(domain.getSize()/c)*(1./6.)
q=whereZero(x[0])+whereZero(x[0]-1.)
mypde_f=LinearSinglePDE(domain)
mypde_f.setSymmetryOn()
mypde_f.setValue(D=1,q=q)
u_f_old=ref_u(x,-dt)
u_f=ref_u(x,0)
mypde_HRZ=LinearSinglePDE(domain)
mypde_HRZ.getSolverOptions().setSolverMethod(SolverOptions.HRZ_LUMPING)
mypde_HRZ.setValue(D=1,q=q)
u_HRZ_old=ref_u(x,-dt)
u_HRZ=ref_u(x,0)
mypde_RS=LinearSinglePDE(domain)
mypde_RS.getSolverOptions().setSolverMethod(SolverOptions.ROWSUM_LUMPING)
mypde_RS.setValue(D=1,q=q)
u_RS_old=ref_u(x,-dt)
u_RS=ref_u(x,0)
l=Locator(domain,[0.5,0.5])
t=0
u=ref_u(x,t)
t_list=[t]
u_list=[l(u)]
f_list=[l(u_f)]
HRZ_list=[l(u_HRZ)]
RS_list=[l(u_RS)]
print(t_list[-1], u_list[-1], f_list[-1], HRZ_list[-1] , RS_list[-1])
while t< 4/n/c:
t+=dt
u=ref_u(x,t)
mypde_f.setValue(X=-c**2*grad(u_f), r=-c**2*u)
mypde_HRZ.setValue(X=-c**2*grad(u_HRZ), r=-c**2*u)
mypde_RS.setValue(X=-c**2*grad(u_RS), r=-c**2*u)
a_f=mypde_f.getSolution()
a_HRZ=mypde_HRZ.getSolution()
a_RS=mypde_RS.getSolution()
u_f, u_f_old = 2*u_f-u_f_old + dt**2*a_f , u_f
u_HRZ, u_HRZ_old = 2*u_HRZ-u_HRZ_old + dt**2*a_HRZ , u_HRZ
u_RS, u_RS_old = 2*u_RS-u_RS_old + dt**2*a_RS , u_RS
t_list.append(t)
u_list.append(l(u))
f_list.append(l(u_f))
HRZ_list.append(l(u_HRZ))
RS_list.append(l(u_RS))
print(t_list[-1], u_list[-1], f_list[-1], HRZ_list[-1] , RS_list[-1])
import matplotlib.pyplot as plt
if getMPIRankWorld() == 0:
plt.clf()
plt.plot(t_list, u_list, '-', label="exact", linewidth=1)
plt.plot(t_list, f_list, '-', label="full", linewidth=1)
plt.plot(t_list, HRZ_list, '-', label="HRZ lumping", linewidth=1)
plt.plot(t_list, RS_list, '-', label="row sum lumping", linewidth=1)
plt.axis([0.,max(t_list),-1.3,1.3])
plt.xlabel('time')
plt.ylabel('displacement')
plt.legend()
plt.savefig('lumping_valet_a_%d.png'%order, format='png')
def runValetAcceleration(order):
domain=finley.Rectangle(100,10,order)
x=domain.getX()
# test Velet scheme
dt=inf(domain.getSize()/c)*(1./6.)
q=whereZero(x[0])+whereZero(x[0]-1.)
mypde_f=LinearSinglePDE(domain)
mypde_f.setSymmetryOn()
mypde_f.setValue(D=1,q=q)
u_f_old=ref_u(x,-dt)
u_f=ref_u(x,0)
mypde_HRZ=LinearSinglePDE(domain)
mypde_HRZ.getSolverOptions().setSolverMethod(SolverOptions.HRZ_LUMPING)
mypde_HRZ.setValue(D=1,q=q)
u_HRZ_old=ref_u(x,-dt)
u_HRZ=ref_u(x,0)
mypde_RS=LinearSinglePDE(domain)
mypde_RS.getSolverOptions().setSolverMethod(SolverOptions.ROWSUM_LUMPING)
mypde_RS.setValue(D=1,q=q)
u_RS_old=ref_u(x,-dt)
u_RS=ref_u(x,0)
l=Locator(domain,[0.5,0.5])
t=0
u=ref_u(x,t)
t_list=[t]
u_list=[l(u)]
f_list=[l(u_f)]
HRZ_list=[l(u_HRZ)]
RS_list=[l(u_RS)]
print(t_list[-1], u_list[-1], f_list[-1], HRZ_list[-1] , RS_list[-1])
while t< 4/n/c:
t+=dt
u=ref_u(x,t)
mypde_f.setValue(X=-c**2*grad(u_f), r=-c**2*u)
mypde_HRZ.setValue(X=-c**2*grad(u_HRZ), r=-c**2*u)
mypde_RS.setValue(X=-c**2*grad(u_RS), r=-c**2*u)
a_f=mypde_f.getSolution()
a_HRZ=mypde_HRZ.getSolution()
a_RS=mypde_RS.getSolution()
u_f, u_f_old = 2*u_f-u_f_old + dt**2*a_f , u_f
u_HRZ, u_HRZ_old = 2*u_HRZ-u_HRZ_old + dt**2*a_HRZ , u_HRZ
u_RS, u_RS_old = 2*u_RS-u_RS_old + dt**2*a_RS , u_RS
t_list.append(t)
u_list.append(l(u))
f_list.append(l(u_f))
HRZ_list.append(l(u_HRZ))
RS_list.append(l(u_RS))
print(t_list[-1], u_list[-1], f_list[-1], HRZ_list[-1] , RS_list[-1])
import matplotlib.pyplot as plt
if getMPIRankWorld() == 0:
plt.clf()
plt.plot(t_list, u_list, '-', label="exact", linewidth=1)
plt.plot(t_list, f_list, '-', label="full", linewidth=1)
plt.plot(t_list, HRZ_list, '-', label="HRZ lumping", linewidth=1)
plt.plot(t_list, RS_list, '-', label="row sum lumping", linewidth=1)
plt.axis([0.,max(t_list),-1.3,1.3])
plt.xlabel('time')
plt.ylabel('displacement')
plt.legend()
plt.savefig('lumping_valet_a_%d.png'%order, format='png')
def runTaylorGalerkinIncremental(order):
domain = finley.Rectangle(100, 10, order)
x = domain.getX()
# test Velet scheme
dt = inf(domain.getSize() / length(v)) * (1.0 / 6.0)
q = whereZero(x[0]) + whereZero(x[0] - 1.0)
mypde_f = LinearSinglePDE(domain)
mypde_f.setSymmetryOn()
mypde_f.setValue(D=1, q=q)
u_f = ref_u(x, 0)
mypde_HRZ = LinearSinglePDE(domain)
mypde_HRZ.getSolverOptions().setSolverMethod(SolverOptions.HRZ_LUMPING)
mypde_HRZ.setValue(D=1, q=q)
u_HRZ = ref_u(x, 0)
mypde_RS = LinearSinglePDE(domain)
mypde_RS.getSolverOptions().setSolverMethod(SolverOptions.ROWSUM_LUMPING)
mypde_RS.setValue(D=1, q=q)
u_RS = ref_u(x, 0)
l = Locator(domain, [0.5, 0.5])
t = 0
u = ref_u(x, t)
t_list = [t]
u_list = [l(u)]
f_list = [l(u_f)]
HRZ_list = [l(u_HRZ)]
RS_list = [l(u_RS)]
print(t_list[-1], u_list[-1], f_list[-1], HRZ_list[-1], RS_list[-1])
while t < 1.0 / Lsup(v):
t += dt
u = ref_u(x, t)
mypde_f.setValue(X=-dt / 2.0 * u_f * v, r=ref_u(x, t - dt / 2) - u_f)
mypde_HRZ.setValue(X=-dt / 2.0 * u_HRZ * v, r=ref_u(x, t - dt / 2) - u_f)
mypde_RS.setValue(X=-dt / 2.0 * u_RS * v, r=ref_u(x, t - dt / 2) - u_f)
u_f_h = u_f + mypde_f.getSolution()
u_HRZ_h = u_HRZ + mypde_HRZ.getSolution()
u_RS_h = u_RS + mypde_RS.getSolution()
mypde_f.setValue(X=-dt * u_f_h * v, r=u - u_f)
mypde_HRZ.setValue(X=-dt * u_HRZ_h * v, r=u - u_HRZ)
mypde_RS.setValue(X=-dt * u_RS_h * v, r=u - u_RS)
u_f = u_f + mypde_f.getSolution()
u_HRZ = u_HRZ + mypde_HRZ.getSolution()
u_RS = u_RS + mypde_RS.getSolution()
t_list.append(t)
u_list.append(l(u))
f_list.append(l(u_f))
HRZ_list.append(l(u_HRZ))
RS_list.append(l(u_RS))
print(t_list[-1], u_list[-1], f_list[-1], HRZ_list[-1], RS_list[-1], " : ", sup(u))
import matplotlib.pyplot as plt
if getMPIRankWorld() == 0:
plt.clf()
plt.plot(t_list, u_list, "-", label="exact", linewidth=1)
plt.plot(t_list, f_list, "-", label="full", linewidth=1)
plt.plot(t_list, HRZ_list, "-", label="HRZ lumping", linewidth=1)
plt.plot(t_list, RS_list, "-", label="row sum lumping", linewidth=1)
plt.axis([0.0, max(t_list), -0.3, 2.0])
plt.xlabel("time")
plt.ylabel("displacement")
plt.legend()
plt.savefig("lumping_SUPG_du_%d.png" % order, format="png")
def __createPDE(self):
"""
Create the PDE and set boundary conditions.
"""
pde = LinearSinglePDE(self.domain, isComplex=False)
optionsG = pde.getSolverOptions()
optionsG.setSolverMethod(SolverOptions.PCG)
pde.setSymmetryOn()
if self.useFastSolver and hasFeature('trilinos'):
optionsG.setPackage(SolverOptions.TRILINOS)
optionsG.setPreconditioner(SolverOptions.AMG)
if self.fixAllFaces:
x=pde.getDomain().getX()[0]
y=pde.getDomain().getX()[1]
z=pde.getDomain().getX()[2]
pde.setValue(q=whereZero(x-inf(x))+whereZero(x-sup(x))+ whereZero(y-inf(y))+whereZero(y-sup(y))+whereZero(z-inf(z)))
else:
z=pde.getDomain().getX()[2]
pde.setValue(q=whereZero(z-inf(z)))
return pde
w_step=max(int(nstep/50),1)*0+1 toler = 0.001 teta1 = 0.5 teta2 = 0.5 teta3 = 1 # =0 split A; =1 split B # create domain: dom=Rectangle(int(nel*L/min(L,H)),int(nel*H/min(L,H)),order=1, l0=L, l1=H) x=dom.getX() momentumStep1=LinearPDESystem(dom) momentumStep1.setValue(q=whereZero(x[0])*[1.,0.]+whereZero(x[1])*[0.,1.]) # fix x0=0 and x1=0 face_mask=whereZero(FunctionOnBoundary(dom).getX()[1]) pressureStep2=LinearSinglePDE(dom) pressureStep2.setReducedOrderOn() pressureStep2.setValue(q=whereZero(x[0]-L)+whereZero(x[1]-H)) momentumStep3=LinearPDESystem(dom) momentumStep3.setValue(q=whereZero(x[0])*[1.,0.]+whereZero(x[1])*[0.,1.]) # # initial values: # U=Vector(0.,Solution(dom)) p=ro*g*(L-ReducedSolution(dom).getX()[0])*(H-ReducedSolution(dom).getX()[1])/3 p=ro*g*(H-ReducedSolution(dom).getX()[1]) dev_stress=Tensor(0.,Function(dom)) t=dt istep=0
class IsostaticPressure(object):
"""
class to calculate isostatic pressure field correction due to gravity forces
"""
def __init__(self,
domain,
p0=0.,
level0=0,
gravity0=-9.81 * U.m * U.sec**(-2),
background_density=2670 * U.kg * U.m**(-3),
gravity_constant=U.Gravitational_Constant,
coordinates=None,
tol=1e-8):
"""
:param domain: domain of the model
:type domain: `Domain`
:param p0: pressure at level0
:type p0: scalar `Data` or ``float``
:param background_density: defines background_density in kg/m^3
:type background_density: ``float``
:param coordinates: defines coordinate system to be used
:type coordinates: ReferenceSystem` or `SpatialCoordinateTransformation`
:param tol: tolerance of underlying PDE
:type tol: positive ``float``
:param level0: pressure for z>=`level0` is set to zero.
:type level0: ``float``
:param gravity0: vertical background gravity at `level0`
:type gravity0: ``float``
"""
DIM = domain.getDim()
self.__domain = domain
self.__trafo = makeTransformation(domain, coordinates)
self.__pde = LinearSinglePDE(domain)
self.__pde.getSolverOptions().setTolerance(tol)
self.__pde.setSymmetryOn()
z = domain.getX()[DIM - 1]
self.__pde.setValue(q=whereNonNegative(z - level0), r=p0)
fw = self.__trafo.getScalingFactors(
)**2 * self.__trafo.getVolumeFactor()
A = self.__pde.createCoefficient("A")
for i in range(DIM):
A[i, i] = fw[i]
self.__pde.setValue(A=A)
z = Function(domain).getX()[DIM - 1]
self.__g_b = 4 * PI * gravity_constant / self.__trafo.getScalingFactors(
)[DIM - 1] * background_density * (level0 - z) + gravity0
self.__rho_b = background_density
def getPressure(self, g=None, rho=None):
"""
return the pressure for gravity force anomaly `g` and
density anomaly `rho`
:param g: gravity anomaly data
:type g: ``Vector``
:param rho: gravity anomaly data
:type rho: ``Scalar``
:return: pressure distribution
:rtype: ``Scalar``
"""
if not g: g = Vector(0., Function(self.__domain))
if not rho: rho = Scalar(0., Function(self.__domain))
g2 = (rho * self.__g_b) * [0, 0, 1] + self.__rho_b * g + rho * g
# Tests need to be updated before the following is uncommented:
#g2=((rho+self.__rho_b) * self.__g_b)*[0,0,1] + self.__rho_b*g + rho*g
d = self.__trafo.getScalingFactors()
V = self.__trafo.getVolumeFactor()
self.__pde.setValue(X=-g2 * d * V)
#self.__pde.setValue(X = g2*d*V)
return self.__pde.getSolution()
def __createPDE(self):
"""
Create the PDE and set boundary conditions.
"""
pde = LinearSinglePDE(
self.domain,
isComplex=True,
)
optionsG = pde.getSolverOptions()
optionsG.setSolverMethod(SolverOptions.DIRECT)
pde.setSymmetryOn()
if self.useFastSolver and hasFeature('trilinos'): # ignored for now!
optionsG.setPackage(SolverOptions.TRILINOS)
optionsG.setPreconditioner(SolverOptions.AMG)
pde.setValue(A=kronecker(self.domain.getDim()))
z = self.domain.getX()[self.domain.getDim() - 1]
t = sup(z)
if self.fixBottom:
b = inf(z)
pde.setValue(q=whereZero(z - t) + whereZero(z - b),
r=(z - b) / (t - b))
else:
pde.setValue(q=whereZero(z - t), r=1.)
return pde
from esys.escript import *
from esys.escript.linearPDEs import LinearSinglePDE
from esys.weipa import saveVTK
try:
from esys.finley import Rectangle
HAVE_FINLEY = True
except ImportError:
HAVE_FINLEY = False
# generate domain:
if not HAVE_FINLEY:
print("Finley module not available")
else:
mydomain=Rectangle(30,30, l0=3, l1=2,
diracPoints=[(1.,1.), (2.,1.)], diracTags=['in', 'out'])
# fix the solution on the boundary
x = mydomain.getX()
gammaD = whereZero(x[0])+whereZero(x[1])+whereZero(x[0]-3.)+whereZero(x[1]-2.)
# fix the solution on the boundary
s=Scalar(0., DiracDeltaFunctions(mydomain))
s.setTaggedValue('in', +1.)
s.setTaggedValue('out', -1.)
# define PDE and get its solution u
mypde = LinearSinglePDE(domain=mydomain)
mypde.setValue(q=gammaD, A=kronecker(2), y_dirac=s)
u = mypde.getSolution()
print("Solution = ",str(u))
# write u to an external file
saveVTK("u.vtu",sol=u)
u0=1/(4.*pi*E*T0)**(DIM/2.)*exp(-length(dom.getX()-getCenter(T0))**2/(4.*E*T0))
print("QUALITY ",QUALITY(T0,u0))
x=Function(dom).getX()
if DIM == 2:
V=OMEGA0*(x[0]*[0,-1]+x[1]*[1,0])
else:
V=OMEGA0*(x[0]*[0,cos(ALPHA),0]+x[1]*[-cos(ALPHA),0,sin(ALPHA)]+x[2]*[0.,-sin(ALPHA),0.])
#===================
fc=TransportPDE(dom,num_equations=1,theta=THETA)
x=Function(dom).getX()
fc.setValue(M=Scalar(1.,Function(dom)),C=V,A=-Scalar(E,Function(dom))*kronecker(dom))
#==============
if TEST_SUPG:
supg=LinearSinglePDE(dom)
supg.setValue(D=1.)
supg.setSolverMethod(supg.LUMPING)
dt_supg=1./(1./inf(dom.getSize()/length(V))+1./inf(dom.getSize()**2/E))*0.3
u_supg=u0*1.
c=0
saveVTK("u.%s.vtu"%c,u=u0)
fc.setInitialSolution(u0)
t=T0
while t<T_END:
print("time step t=",t+dt)
u=fc.solve(dt)
if TEST_SUPG:
#========== supg tests ================
nn=max(ceil(dt/dt_supg),1.)
def runTaylorGalerkinIncremental(order):
domain = finley.Rectangle(100, 10, order)
x = domain.getX()
# test Velet scheme
dt = inf(domain.getSize() / length(v)) * (1. / 6.)
q = whereZero(x[0]) + whereZero(x[0] - 1.)
mypde_f = LinearSinglePDE(domain)
mypde_f.setSymmetryOn()
mypde_f.setValue(D=1, q=q)
u_f = ref_u(x, 0)
mypde_HRZ = LinearSinglePDE(domain)
mypde_HRZ.getSolverOptions().setSolverMethod(SolverOptions.HRZ_LUMPING)
mypde_HRZ.setValue(D=1, q=q)
u_HRZ = ref_u(x, 0)
mypde_RS = LinearSinglePDE(domain)
mypde_RS.getSolverOptions().setSolverMethod(SolverOptions.ROWSUM_LUMPING)
mypde_RS.setValue(D=1, q=q)
u_RS = ref_u(x, 0)
l = Locator(domain, [0.5, 0.5])
t = 0
u = ref_u(x, t)
t_list = [t]
u_list = [l(u)]
f_list = [l(u_f)]
HRZ_list = [l(u_HRZ)]
RS_list = [l(u_RS)]
print(t_list[-1], u_list[-1], f_list[-1], HRZ_list[-1], RS_list[-1])
while t < 1. / Lsup(v):
t += dt
u = ref_u(x, t)
mypde_f.setValue(X=-dt / 2. * u_f * v, r=ref_u(x, t - dt / 2) - u_f)
mypde_HRZ.setValue(X=-dt / 2. * u_HRZ * v,
r=ref_u(x, t - dt / 2) - u_f)
mypde_RS.setValue(X=-dt / 2. * u_RS * v, r=ref_u(x, t - dt / 2) - u_f)
u_f_h = u_f + mypde_f.getSolution()
u_HRZ_h = u_HRZ + mypde_HRZ.getSolution()
u_RS_h = u_RS + mypde_RS.getSolution()
mypde_f.setValue(X=-dt * u_f_h * v, r=u - u_f)
mypde_HRZ.setValue(X=-dt * u_HRZ_h * v, r=u - u_HRZ)
mypde_RS.setValue(X=-dt * u_RS_h * v, r=u - u_RS)
u_f = u_f + mypde_f.getSolution()
u_HRZ = u_HRZ + mypde_HRZ.getSolution()
u_RS = u_RS + mypde_RS.getSolution()
t_list.append(t)
u_list.append(l(u))
f_list.append(l(u_f))
HRZ_list.append(l(u_HRZ))
RS_list.append(l(u_RS))
print(t_list[-1], u_list[-1], f_list[-1], HRZ_list[-1], RS_list[-1],
" : ", sup(u))
import matplotlib.pyplot as plt
if getMPIRankWorld() == 0:
plt.clf()
plt.plot(t_list, u_list, '-', label="exact", linewidth=1)
plt.plot(t_list, f_list, '-', label="full", linewidth=1)
plt.plot(t_list, HRZ_list, '-', label="HRZ lumping", linewidth=1)
plt.plot(t_list, RS_list, '-', label="row sum lumping", linewidth=1)
plt.axis([0., max(t_list), -.3, 2.])
plt.xlabel('time')
plt.ylabel('displacement')
plt.legend()
plt.savefig('lumping_SUPG_du_%d.png' % order, format='png')
x = Function(dom).getX()
if DIM == 2:
V = OMEGA0 * (x[0] * [0, -1] + x[1] * [1, 0])
else:
V = OMEGA0 * (x[0] * [0, cos(ALPHA), 0] + x[1] *
[-cos(ALPHA), 0, sin(ALPHA)] + x[2] * [0., -sin(ALPHA), 0.])
#===================
fc = TransportPDE(dom, num_equations=1, theta=THETA)
x = Function(dom).getX()
fc.setValue(M=Scalar(1., Function(dom)),
C=V,
A=-Scalar(E, Function(dom)) * kronecker(dom))
#==============
if TEST_SUPG:
supg = LinearSinglePDE(dom)
supg.setValue(D=1.)
supg.setSolverMethod(supg.LUMPING)
dt_supg = 1. / (1. / inf(dom.getSize() / length(V)) +
1. / inf(dom.getSize()**2 / E)) * 0.3
u_supg = u0 * 1.
c = 0
saveVTK("u.%s.vtu" % c, u=u0)
fc.setInitialSolution(u0)
t = T0
while t < T_END:
print("time step t=", t + dt)
u = fc.solve(dt)
if TEST_SUPG:
#========== supg tests ================
w_step=max(int(nstep/50),1)*0+1 toler = 0.001 teta1 = 0.5 teta2 = 0.5 teta3 = 1 # =0 split A; =1 split B # create domain: dom=Rectangle(int(nel*L/min(L,H)),int(nel*H/min(L,H)),order=1, l0=L, l1=H) x=dom.getX() momentumStep1=LinearPDESystem(dom) momentumStep1.setValue(q=whereZero(x[0])*[1.,0.]+whereZero(x[1])*[0.,1.]) # fix x0=0 and x1=0 face_mask=whereZero(FunctionOnBoundary(dom).getX()[1]) pressureStep2=LinearSinglePDE(dom) pressureStep2.setReducedOrderOn() pressureStep2.setValue(q=whereZero(x[0]-L)+whereZero(x[1]-H)) momentumStep3=LinearPDESystem(dom) momentumStep3.setValue(q=whereZero(x[0])*[1.,0.]+whereZero(x[1])*[0.,1.]) # # initial values: # U=Vector(0.,Solution(dom)) p=ro*g*(L-ReducedSolution(dom).getX()[0])*(H-ReducedSolution(dom).getX()[1])/3 p=ro*g*(H-ReducedSolution(dom).getX()[1]) dev_stress=Tensor(0.,Function(dom)) t=dt istep=0
from esys.escript import *
from esys.weipa import saveVTK, saveSilo
from esys.escript.linearPDEs import LinearSinglePDE, SolverOptions
from esys.finley import ReadGmsh
from esys.escript.pdetools import Locator
print("read in mesh")
domain = ReadGmsh("simplemesh.msh", 3, optimize=True)
pde = LinearSinglePDE(domain, isComplex=False)
pde.setSymmetryOn()
x = domain.getX()
pde.setValue(A=kronecker(3), Y=1, q=whereZero(x[0] - inf(x[0])))
options = pde.getSolverOptions()
options.setPackage(SolverOptions.TRILINOS)
options.setSolverMethod(SolverOptions.PCG)
options.setPreconditioner(SolverOptions.AMG)
options.setTrilinosParameter("multigrid algorithm", "sa")
options.setTrilinosParameter("sa: damping factor", 1.3)
options.setTrilinosParameter("max levels", 10)
options.setTrilinosParameter("coarse: max size", 2000)
options.setTrilinosParameter("coarse: type", "SuperLU")
options.setTrilinosParameter("verbosity", "low")
print("solve pde")
u = pde.getSolution()
saveSilo("asimple", u=u)
print("finished")
def __createPDE(self):
"""
Create the PDE and set boundary conditions.
"""
pde = LinearSinglePDE(self.domain, isComplex=False)
optionsG = pde.getSolverOptions()
optionsG.setSolverMethod(SolverOptions.PCG)
pde.setSymmetryOn()
assert self.source.getFunctionSpace() == DiracDeltaFunctions(self.domain)
sigma=interpolate(self.sigma, Function(self.domain))
pde.setValue(A=sigma*kronecker(self.domain), y_dirac=self.source)
if self.useFastSolver and hasFeature('trilinos'):
optionsG.setPackage(SolverOptions.TRILINOS)
optionsG.setPreconditioner(SolverOptions.AMG)
if self.fixAllFaces:
x=pde.getDomain().getX()[0]
y=pde.getDomain().getX()[1]
z=pde.getDomain().getX()[2]
pde.setValue(q=whereZero(x-inf(x))+whereZero(x-sup(x))+ whereZero(y-inf(y))+whereZero(y-sup(y))+whereZero(z-inf(z)))
else:
z=pde.getDomain().getX()[2]
pde.setValue(q=whereZero(z-inf(z)))
return pde
class ForwardModelWithPotential(ForwardModel):
"""
Base class for a forward model using a potential such as magnetic or
gravity. It defines a cost function:
defect = 1/2 sum_s integrate( ( weight_i[s] * ( r_i - data_i[s] ) )**2 )
where s runs over the survey, weight_i are weighting factors, data_i are
the data, and r_i are the results produced by the forward model.
It is assumed that the forward model is produced through postprocessing
of the solution of a potential PDE.
"""
def __init__(self,
domain,
w,
data,
coordinates=None,
fixPotentialAtBottom=False,
tol=1e-8):
"""
initializes a new forward model with potential.
:param domain: domain of the model
:type domain: `Domain`
:param w: data weighting factors
:type w: ``Vector`` or list of ``Vector``
:param data: data
:type data: ``Vector`` or list of ``Vector``
:param coordinates: defines coordinate system to be used
:type coordinates: `ReferenceSystem` or `SpatialCoordinateTransformation`
:param fixPotentialAtBottom: if true potential is fixed to zero at the bottom of the domain
in addition to the top.
:type fixPotentialAtBottom: ``bool``
:param tol: tolerance of underlying PDE
:type tol: positive ``float``
"""
super(ForwardModelWithPotential, self).__init__()
self.__domain = domain
self.__trafo = makeTransformation(domain, coordinates)
try:
n = len(w)
m = len(data)
if not m == n:
raise ValueError("Length of weight and data must be the same.")
self.__weight = w
self.__data = data
except TypeError:
self.__weight = [w]
self.__data = [data]
BX = boundingBox(domain)
DIM = domain.getDim()
x = domain.getX()
self.__pde = LinearSinglePDE(domain)
self.__pde.getSolverOptions().setTolerance(tol)
self.__pde.setSymmetryOn()
z = x[DIM - 1]
q0 = whereZero(z - BX[DIM - 1][1])
if fixPotentialAtBottom: q0 += whereZero(z - BX[DIM - 1][0])
self.__pde.setValue(q=q0)
self.edge_lengths = np.asarray(boundingBoxEdgeLengths(domain))
self.diameter = 1. / sqrt(sum(1. / self.edge_lengths**2))
self.__origweight = []
for s in range(len(self.__weight)):
# save a copy of the original weights in case of rescaling
self.__origweight.append(1. * self.__weight[s])
if not self.__trafo.isCartesian():
fd = 1. / self.__trafo.getScalingFactors()
fw = self.__trafo.getScalingFactors() * sqrt(
self.__trafo.getVolumeFactor())
for s in range(len(self.__weight)):
self.__weight[s] = fw * self.__weight[s]
self.__data[s] = fd * self.__data[s]
def _rescaleWeights(self, scale=1., fetch_factor=1.):
"""
rescales the weights such that
*sum_s integrate( ( weight_i[s] *data_i[s]) (weight_j[s]*1/L_j) * L**2 * fetch_factor )=scale*
"""
if not scale > 0:
raise ValueError("Value for scale must be positive.")
A = 0
# copy back original weights before rescaling
self.__weight = [1. * ow for ow in self.__origweight]
for s in range(len(self.__weight)):
if self.__data[s].getShape() == ():
ff = self.__weight[s]**2 * self.__data[s] / length(
self.edge_lengths)
else:
ff = inner(self.__weight[s], self.__data[s]) * inner(
self.__weight[s], 1 / self.edge_lengths)
A += integrate(abs(ff * fetch_factor))
if A > 0:
A = sqrt(scale / A) / self.diameter
if not self.__trafo.isCartesian():
A *= self.__trafo.getScalingFactors() * sqrt(
self.__trafo.getVolumeFactor())
for s in range(len(self.__weight)):
self.__weight[s] *= A
else:
raise ValueError("Rescaling of weights failed.")
def getDomain(self):
"""
Returns the domain of the forward model.
:rtype: `Domain`
"""
return self.__domain
def getMisfitWeights(self):
"""
Returns the weights of the misfit function
:rtype: ``list`` of ``Data``
"""
return self.__weight
def getData(self):
"""
Returns the data
:rtype: ``list`` of ``Data``
"""
return self.__data
def getDataFunctionSpace(self):
"""
Returns the ``FunctionSpace`` of the data
:rtype: ``FunctionSpace``
"""
return self.getData()[0].getFunctionSpace()
def getCoordinateTransformation(self):
"""
returns the coordinate transformation being used
:rtype: ``CoordinateTransformation``
"""
return self.__trafo
def getPDE(self):
"""
Return the underlying PDE.
:rtype: `LinearPDE`
"""
return self.__pde
def _getDefect(self, result):
"""
Returns the defect value.
:param result: a result vector
:type result: `Vector`
:rtype: ``float``
"""
A = 0.
for s in range(len(self.__weight)):
A += integrate(inner(self.__weight[s], self.__data[s] - result)**2)
return A / 2
def getDefectGradient(self, result):
Y = 0.
for s in range(len(self.__weight)):
Y = inner(self.__weight[s],
self.__data[s] - result) * self.__weight[s] + Y
return Y
def getSurvey(self, index=None):
"""
Returns the pair (data_index, weight_index), where data_i is the data
of survey i, weight_i is the weighting factor for survey i.
If index is None, all surveys will be returned in a pair of lists.
"""
if index is None:
return self.__data, self.__weight
if index >= len(self.__data):
raise IndexError("Forward model only has %d surveys" %
len(self.__data))
return self.__data[index], self.__weight[index]
class IsostaticPressure(object):
"""
class to calculate isostatic pressure field correction due to gravity forces
"""
def __init__(self, domain, p0=0., level0=0, gravity0=-9.81*U.m*U.sec**(-2),
background_density=2670* U.kg*U.m**(-3),
gravity_constant=U.Gravitational_Constant,
coordinates=None, tol=1e-8):
"""
:param domain: domain of the model
:type domain: `Domain`
:param p0: pressure at level0
:type p0: scalar `Data` or ``float``
:param background_density: defines background_density in kg/m^3
:type background_density: ``float``
:param coordinates: defines coordinate system to be used
:type coordinates: ReferenceSystem` or `SpatialCoordinateTransformation`
:param tol: tolerance of underlying PDE
:type tol: positive ``float``
:param level0: pressure for z>=`level0` is set to zero.
:type level0: ``float``
:param gravity0: vertical background gravity at `level0`
:type gravity0: ``float``
"""
DIM=domain.getDim()
self.__domain = domain
self.__trafo=makeTransformation(domain, coordinates)
self.__pde=LinearSinglePDE(domain)
self.__pde.getSolverOptions().setTolerance(tol)
self.__pde.setSymmetryOn()
z = domain.getX()[DIM-1]
self.__pde.setValue(q=whereNonNegative(z-level0), r=p0)
fw = self.__trafo.getScalingFactors()**2 * self.__trafo.getVolumeFactor()
A=self.__pde.createCoefficient("A")
for i in range(DIM): A[i,i]=fw[i]
self.__pde.setValue(A=A)
z = Function(domain).getX()[DIM-1]
self.__g_b= 4*PI*gravity_constant/self.__trafo.getScalingFactors()[DIM-1]*background_density*(level0-z) + gravity0
self.__rho_b=background_density
def getPressure(self, g = None, rho=None):
"""
return the pressure for gravity force anomaly `g` and
density anomaly `rho`
:param g: gravity anomaly data
:type g: ``Vector``
:param rho: gravity anomaly data
:type rho: ``Scalar``
:return: pressure distribution
:rtype: ``Scalar`
"""
if not g: g=Vector(0., Function(self.__domain))
if not rho: rho=Scalar(0., Function(self.__domain))
g2=(rho * self.__g_b)*[0,0,1] + self.__rho_b*g + rho*g
# Tests need to be updated before the following is uncommented:
#g2=((rho+self.__rho_b) * self.__g_b)*[0,0,1] + self.__rho_b*g + rho*g
d=self.__trafo.getScalingFactors()
V= self.__trafo.getVolumeFactor()
self.__pde.setValue(X = -g2*d*V)
#self.__pde.setValue(X = g2*d*V)
return self.__pde.getSolution()
def __init__(self,
domain,
w,
data,
coordinates=None,
fixPotentialAtBottom=False,
tol=1e-8):
"""
initializes a new forward model with potential.
:param domain: domain of the model
:type domain: `Domain`
:param w: data weighting factors
:type w: ``Vector`` or list of ``Vector``
:param data: data
:type data: ``Vector`` or list of ``Vector``
:param coordinates: defines coordinate system to be used
:type coordinates: `ReferenceSystem` or `SpatialCoordinateTransformation`
:param fixPotentialAtBottom: if true potential is fixed to zero at the bottom of the domain
in addition to the top.
:type fixPotentialAtBottom: ``bool``
:param tol: tolerance of underlying PDE
:type tol: positive ``float``
"""
super(ForwardModelWithPotential, self).__init__()
self.__domain = domain
self.__trafo = makeTransformation(domain, coordinates)
try:
n = len(w)
m = len(data)
if not m == n:
raise ValueError("Length of weight and data must be the same.")
self.__weight = w
self.__data = data
except TypeError:
self.__weight = [w]
self.__data = [data]
BX = boundingBox(domain)
DIM = domain.getDim()
x = domain.getX()
self.__pde = LinearSinglePDE(domain)
self.__pde.getSolverOptions().setTolerance(tol)
self.__pde.setSymmetryOn()
z = x[DIM - 1]
q0 = whereZero(z - BX[DIM - 1][1])
if fixPotentialAtBottom: q0 += whereZero(z - BX[DIM - 1][0])
self.__pde.setValue(q=q0)
self.edge_lengths = np.asarray(boundingBoxEdgeLengths(domain))
self.diameter = 1. / sqrt(sum(1. / self.edge_lengths**2))
self.__origweight = []
for s in range(len(self.__weight)):
# save a copy of the original weights in case of rescaling
self.__origweight.append(1. * self.__weight[s])
if not self.__trafo.isCartesian():
fd = 1. / self.__trafo.getScalingFactors()
fw = self.__trafo.getScalingFactors() * sqrt(
self.__trafo.getVolumeFactor())
for s in range(len(self.__weight)):
self.__weight[s] = fw * self.__weight[s]
self.__data[s] = fd * self.__data[s]
try:
from esys.finley import Rectangle
HAVE_FINLEY = True
except ImportError:
HAVE_FINLEY = False
# generate domain:
if not HAVE_FINLEY:
print("Finley module not available")
else:
mydomain = Rectangle(30,
30,
l0=3,
l1=2,
diracPoints=[(1., 1.), (2., 1.)],
diracTags=['in', 'out'])
# fix the solution on the boundary
x = mydomain.getX()
gammaD = whereZero(x[0]) + whereZero(
x[1]) + whereZero(x[0] - 3.) + whereZero(x[1] - 2.)
# fix the solution on the boundary
s = Scalar(0., DiracDeltaFunctions(mydomain))
s.setTaggedValue('in', +1.)
s.setTaggedValue('out', -1.)
# define PDE and get its solution u
mypde = LinearSinglePDE(domain=mydomain)
mypde.setValue(q=gammaD, A=kronecker(2), y_dirac=s)
u = mypde.getSolution()
print("Solution = ", str(u))
# write u to an external file
saveVTK("u.vtu", sol=u)
class ForwardModelWithPotential(ForwardModel):
"""
Base class for a forward model using a potential such as magnetic or
gravity. It defines a cost function:
defect = 1/2 sum_s integrate( ( weight_i[s] * ( r_i - data_i[s] ) )**2 )
where s runs over the survey, weight_i are weighting factors, data_i are
the data, and r_i are the results produced by the forward model.
It is assumed that the forward model is produced through postprocessing
of the solution of a potential PDE.
"""
def __init__(self, domain, w, data, coordinates=None,
fixPotentialAtBottom=False,
tol=1e-8):
"""
initializes a new forward model with potential.
:param domain: domain of the model
:type domain: `Domain`
:param w: data weighting factors
:type w: ``Vector`` or list of ``Vector``
:param data: data
:type data: ``Vector`` or list of ``Vector``
:param coordinates: defines coordinate system to be used
:type coordinates: `ReferenceSystem` or `SpatialCoordinateTransformation`
:param fixPotentialAtBottom: if true potential is fixed to zero at the bottom of the domain
in addition to the top.
:type fixPotentialAtBottom: ``bool``
:param tol: tolerance of underlying PDE
:type tol: positive ``float``
"""
super(ForwardModelWithPotential, self).__init__()
self.__domain = domain
self.__trafo = makeTransformation(domain, coordinates)
try:
n=len(w)
m=len(data)
if not m == n:
raise ValueError("Length of weight and data must be the same.")
self.__weight = w
self.__data = data
except TypeError:
self.__weight = [w]
self.__data = [data]
BX = boundingBox(domain)
DIM = domain.getDim()
x = domain.getX()
self.__pde=LinearSinglePDE(domain)
self.__pde.getSolverOptions().setTolerance(tol)
self.__pde.setSymmetryOn()
z=x[DIM-1]
q0=whereZero(z-BX[DIM-1][1])
if fixPotentialAtBottom: q0+=whereZero(z-BX[DIM-1][0])
self.__pde.setValue(q=q0)
self.edge_lengths=np.asarray(boundingBoxEdgeLengths(domain))
self.diameter=1./sqrt(sum(1./self.edge_lengths**2))
self.__origweight=[]
for s in range(len(self.__weight)):
# save a copy of the original weights in case of rescaling
self.__origweight.append(1.*self.__weight[s])
if not self.__trafo.isCartesian():
fd=1./self.__trafo.getScalingFactors()
fw=self.__trafo.getScalingFactors()*sqrt(self.__trafo.getVolumeFactor())
for s in range(len(self.__weight)):
self.__weight[s] = fw * self.__weight[s]
self.__data[s] = fd * self.__data[s]
def _rescaleWeights(self, scale=1., fetch_factor=1.):
"""
rescales the weights such that
*sum_s integrate( ( weight_i[s] *data_i[s]) (weight_j[s]*1/L_j) * L**2 * fetch_factor )=scale*
"""
if not scale > 0:
raise ValueError("Value for scale must be positive.")
A=0
# copy back original weights before rescaling
self.__weight=[1.*ow for ow in self.__origweight]
for s in range(len(self.__weight)):
A += integrate(abs(inner(self.__weight[s], self.__data[s]) * inner(self.__weight[s], 1/self.edge_lengths) * fetch_factor))
if A > 0:
A=sqrt(scale/A)/self.diameter
if not self.__trafo.isCartesian():
A*=self.__trafo.getScalingFactors()*sqrt(self.__trafo.getVolumeFactor())
for s in range(len(self.__weight)):
self.__weight[s]*=A
else:
raise ValueError("Rescaling of weights failed.")
def getDomain(self):
"""
Returns the domain of the forward model.
:rtype: `Domain`
"""
return self.__domain
def getCoordinateTransformation(self):
"""
returns the coordinate transformation being used
:rtype: ``CoordinateTransformation``
"""
return self.__trafo
def getPDE(self):
"""
Return the underlying PDE.
:rtype: `LinearPDE`
"""
return self.__pde
def _getDefect(self, result):
"""
Returns the defect value.
:param result: a result vector
:type result: `Vector`
:rtype: ``float``
"""
A=0.
for s in range(len(self.__weight)):
A += integrate( inner(self.__weight[s], self.__data[s]-result)**2 )
return A/2
def getDefectGradient(self, result):
Y=0.
for s in range(len(self.__weight)):
Y = inner(self.__weight[s], self.__data[s]-result) * self.__weight[s] + Y
return Y
def getSurvey(self, index=None):
"""
Returns the pair (data_index, weight_index), where data_i is the data
of survey i, weight_i is the weighting factor for survey i.
If index is None, all surveys will be returned in a pair of lists.
"""
if index is None:
return self.__data, self.__weight
if index>=len(self.__data):
raise IndexError("Forward model only has %d surveys"%len(self.__data))
return self.__data[index], self.__weight[index]
