Files
simpeg/SimPEG/inverse/Inversion.py
T
2013-11-07 17:42:24 -08:00

278 lines
9.0 KiB
Python

import numpy as np
import scipy.sparse as sp
import SimPEG
from SimPEG.utils import sdiag, mkvc, setKwargs, checkStoppers, printStoppers
from Optimize import Remember
from BetaSchedule import Cooling
class BaseInversion(object):
"""docstring for BaseInversion"""
maxIter = 1
name = 'BaseInversion'
debug = False
beta0 = 1e4
def __init__(self, prob, reg, opt, **kwargs):
setKwargs(self, **kwargs)
self.prob = prob
self.reg = reg
self.opt = opt
self.opt.parent = self
self.stoppers = [SimPEG.inverse.StoppingCriteria.iteration, SimPEG.inverse.StoppingCriteria.phi_d_target_Inversion]
# Check if we have inserted printers into the optimization
if not np.any([p is SimPEG.inverse.IterationPrinters.phi_d for p in self.opt.printers]):
self.opt.printers.insert(1,SimPEG.inverse.IterationPrinters.beta)
self.opt.printers.insert(2,SimPEG.inverse.IterationPrinters.phi_d)
self.opt.printers.insert(3,SimPEG.inverse.IterationPrinters.phi_m)
self.opt.stoppers.append(SimPEG.inverse.StoppingCriteria.phi_d_target_Minimize)
@property
def Wd(self):
"""
Standard deviation weighting matrix.
"""
if getattr(self,'_Wd',None) is None:
eps = np.linalg.norm(mkvc(self.prob.dobs),2)*1e-5
self._Wd = 1/(abs(self.prob.dobs)*self.prob.std+eps)
return self._Wd
@property
def phi_d_target(self):
"""
target for phi_d
By default this is the number of data.
Note that we do not set the target if it is None, but we return the default value.
"""
if getattr(self, '_phi_d_target', None) is None:
return self.prob.dobs.size #
return self._phi_d_target
@phi_d_target.setter
def phi_d_target(self, value):
self._phi_d_target = value
def run(self, m0):
self.startup(m0)
while True:
self._beta = self.getBeta()
self.m = self.opt.minimize(self.evalFunction, self.m)
self.doEndIteration()
if self.stoppingCriteria(): break
self.printDone()
return self.m
def startup(self, m0):
"""
**startup** is called at the start of any new run call.
If you have things that also need to run on startup, you can create a method::
def _startup*(self, x0):
pass
Where the * can be any string. If present, _startup* will be called at the start of the default startup call.
You may also completely overwrite this function.
:param numpy.ndarray x0: initial x
:rtype: None
:return: None
"""
for method in [posible for posible in dir(self) if '_startup' in posible]:
if self.debug: print 'startup is calling self.'+method
getattr(self,method)(m0)
self.m = m0
self._iter = 0
self._beta = None
def doEndIteration(self):
"""
**doEndIteration** is called at the end of each run iteration.
If you have things that also need to run at the end of every iteration, you can create a method::
def _doEndIteration*(self, xt):
pass
Where the * can be any string. If present, _doEndIteration* will be called at the start of the default doEndIteration call.
You may also completely overwrite this function.
:param numpy.ndarray xt: tested new iterate that ensures a descent direction.
:rtype: None
:return: None
"""
for method in [posible for posible in dir(self) if '_doEndIteration' in posible]:
if self.debug: print 'doEndIteration is calling self.'+method
getattr(self,method)()
# store old values
self.phi_d_last = self.phi_d
self.phi_m_last = self.phi_m
self._iter += 1
def getBeta(self):
return self.beta0
def stoppingCriteria(self):
if self.debug: print 'checking stoppingCriteria'
return checkStoppers(self, self.stoppers)
def printDone(self):
"""
**printDone** is called at the end of the inversion routine.
"""
printStoppers(self, self.stoppers)
def evalFunction(self, m, return_g=True, return_H=True):
u = self.prob.field(m)
phi_d = self.dataObj(m, u)
phi_m = self.reg.modelObj(m)
self.phi_d = phi_d
self.phi_m = phi_m
f = phi_d + self._beta * phi_m
out = (f,)
if return_g:
phi_dDeriv = self.dataObjDeriv(m, u=u)
phi_mDeriv = self.reg.modelObjDeriv(m)
g = phi_dDeriv + self._beta * phi_mDeriv
out += (g,)
if return_H:
def H_fun(v):
phi_d2Deriv = self.dataObj2Deriv(m, v, u=u)
phi_m2Deriv = self.reg.modelObj2Deriv(m)*v
return phi_d2Deriv + self._beta * phi_m2Deriv
operator = sp.linalg.LinearOperator( (m.size, m.size), H_fun, dtype=float )
out += (operator,)
return out if len(out) > 1 else out[0]
def dataObj(self, m, u=None):
"""
:param numpy.array m: geophysical model
:param numpy.array u: fields
:rtype: float
:return: data misfit
The data misfit using an l_2 norm is:
.. math::
\mu_\\text{data} = {1\over 2}\left| \mathbf{W} \circ (\mathbf{d}_\\text{pred} - \mathbf{d}_\\text{obs}) \\right|_2^2
Where P is a projection matrix that brings the field on the full domain to the data measurement locations;
u is the field of interest; d_obs is the observed data; and W is the weighting matrix.
"""
# TODO: ensure that this is a data is vector and Wd is a matrix.
R = self.Wd*self.prob.dataResidual(m, u=u)
R = mkvc(R)
return 0.5*np.vdot(R, R)
def dataObjDeriv(self, m, u=None):
"""
:param numpy.array m: geophysical model
:param numpy.array u: fields
:rtype: numpy.array
:return: data misfit derivative
The data misfit using an l_2 norm is:
.. math::
\mu_\\text{data} = {1\over 2}\left| \mathbf{W} \circ (\mathbf{d}_\\text{pred} - \mathbf{d}_\\text{obs}) \\right|_2^2
If the field, u, is provided, the calculation of the data is fast:
.. math::
\mathbf{d}_\\text{pred} = \mathbf{Pu(m)}
\mathbf{R} = \mathbf{W} \circ (\mathbf{d}_\\text{pred} - \mathbf{d}_\\text{obs})
Where P is a projection matrix that brings the field on the full domain to the data measurement locations;
u is the field of interest; d_obs is the observed data; and W is the weighting matrix.
The derivative of this, with respect to the model, is:
.. math::
\\frac{\partial \mu_\\text{data}}{\partial \mathbf{m}} = \mathbf{J}^\\top \mathbf{W \circ R}
"""
if u is None:
u = self.prob.field(m)
R = self.Wd*self.prob.dataResidual(m, u=u)
dmisfit = self.prob.Jt(m, self.Wd * R, u=u)
return dmisfit
def dataObj2Deriv(self, m, v, u=None):
"""
:param numpy.array m: geophysical model
:param numpy.array u: fields
:rtype: numpy.array
:return: data misfit derivative
The data misfit using an l_2 norm is:
.. math::
\mu_\\text{data} = {1\over 2}\left| \mathbf{W} \circ (\mathbf{d}_\\text{pred} - \mathbf{d}_\\text{obs}) \\right|_2^2
If the field, u, is provided, the calculation of the data is fast:
.. math::
\mathbf{d}_\\text{pred} = \mathbf{Pu(m)}
\mathbf{R} = \mathbf{W} \circ (\mathbf{d}_\\text{pred} - \mathbf{d}_\\text{obs})
Where P is a projection matrix that brings the field on the full domain to the data measurement locations;
u is the field of interest; d_obs is the observed data; and W is the weighting matrix.
The derivative of this, with respect to the model, is:
.. math::
\\frac{\partial \mu_\\text{data}}{\partial \mathbf{m}} = \mathbf{J}^\\top \mathbf{W \circ R}
\\frac{\partial^2 \mu_\\text{data}}{\partial^2 \mathbf{m}} = \mathbf{J}^\\top \mathbf{W \circ W J}
"""
if u is None:
u = self.prob.field(m)
R = self.Wd*self.prob.dataResidual(m, u=u)
# TODO: abstract to different norms a little cleaner.
# \/ it goes here. in l2 it is the identity.
dmisfit = self.prob.Jt_approx(m, self.Wd * self.Wd * self.prob.J_approx(m, v, u=u), u=u)
return dmisfit
class Inversion(Cooling, Remember, BaseInversion):
maxIter = 10
name = "SimPEG Inversion"
def __init__(self, prob, reg, opt, **kwargs):
BaseInversion.__init__(self, prob, reg, opt, **kwargs)