#    Medium[ii,:] = smoothperturb_fn.vector().array()

    print '\t{:12s} {:10s} {:12s} {:12s} {:12s} {:10s} \t{:10s} {:12s} {:12s}'.format(\
    'iter', 'cost', 'misfit', 'reg', '|G|', 'medmisf', 'a_ls', 'tol_cg', 'n_cg')
    dtruenorm = a_target_fn.vector().inner(waveobj.Mass * a_target_fn.vector())
    ######### Inverse problem
    #waveobj.update_PDE({'a':a_initial_fn})
    waveobj.solvefwd_cost()
    myplot.set_varname('a0')
    myplot.plot_vtk(waveobj.PDE.a)
    tolgrad = 1e-10
    tolcost = 1e-14
    check = False
    for iter in xrange(50):
        # gradient
        waveobj.solveadj_constructgrad()
        gradnorm = waveobj.MGv.inner(waveobj.Grad.vector())
        if iter == 0: gradnorm0 = gradnorm
        diff = waveobj.PDE.a.vector() - a_target_fn.vector()
        medmisfit = diff.inner(waveobj.Mass * diff)
        if check and iter % 5 == 1:
            checkgradfd_med(waveobj, Medium, 1e-6, [1e-4, 1e-5, 1e-6])
            checkhessfd_med(waveobj, Medium, 1e-6, [1e-4, 1e-5, 1e-6])
        print '{:12d} {:12.4e} {:12.2e} {:12.2e} {:11.4e} {:10.2e} ({:4.2f})'.\
        format(iter, waveobj.cost, waveobj.cost_misfit, waveobj.cost_reg, \
        gradnorm, medmisfit, medmisfit/dtruenorm),
        # plots
        #myplot.plot_timeseries(waveobj.solfwd, 'p'+str(iter), 0, skip, dl.Function(V))
        myplot.set_varname('a' + str(iter))
        myplot.plot_vtk(waveobj.PDE.a)
        myplot.set_varname('grad' + str(iter))
def run_test(fpeak, lambdamin, lambdamax, Nxy, tfilterpts, r, Dt, skip):
    h = 1. / Nxy
    checkdt(Dt, h, r, np.sqrt(lambdamax), True)
    mesh = dl.UnitSquareMesh(Nxy, Nxy)
    Vl = dl.FunctionSpace(mesh, 'Lagrange', 1)
    V = dl.FunctionSpace(mesh, 'Lagrange', r)
    fctV = dl.Function(V)
    # set up plots:
    filename, ext = splitext(sys.argv[0])
    if isdir(filename + '/'): rmtree(filename + '/')
    myplot = PlotFenics(filename)
    # source:
    Ricker = RickerWavelet(fpeak, 1e-10)
    Pt = PointSources(V, [[0.5, 0.5]])
    mydelta = Pt[0].array()

    def mysrc(tt):
        return Ricker(tt) * mydelta

    # target medium:
    lambda_target = dl.Expression('lmin + x[0]*(lmax-lmin)', \
    lmin=lambdamin, lmax=lambdamax)
    lambda_target_fn = dl.interpolate(lambda_target, Vl)
    myplot.set_varname('lambda_target')
    myplot.plot_vtk(lambda_target_fn)
    # initial medium:
    lambda_init = dl.Constant(lambdamin)
    lambda_init_fn = dl.interpolate(lambda_init, Vl)
    myplot.set_varname('lambda_init')
    myplot.plot_vtk(lambda_init_fn)
    # observation operator:
    #obspts = [[0.2, 0.5], [0.5, 0.2], [0.5, 0.8], [0.8, 0.5]]
    obspts = [[0.2, ii/10.] for ii in range(2,9)] + \
    [[0.8, ii/10.] for ii in range(2,9)] + \
    [[ii/10., 0.2] for ii in range(3,8)] + \
    [[ii/10., 0.8] for ii in range(3,8)]
    obsop = TimeObsPtwise({'V': V, 'Points': obspts}, tfilterpts)
    # define pde operator:
    wavepde = AcousticWave({'V': V, 'Vl': Vl, 'Vr': Vl})
    wavepde.timestepper = 'backward'
    wavepde.lump = True
    wavepde.set_abc(mesh, LeftRight(), True)
    wavepde.update({'lambda':lambda_target_fn, 'rho':1.0, \
    't0':t0, 'tf':tf, 'Dt':Dt, 'u0init':dl.Function(V), 'utinit':dl.Function(V)})
    wavepde.ftime = mysrc
    # define objective function:
    waveobj = ObjectiveAcoustic(wavepde)
    waveobj.obsop = obsop
    # data
    print 'generate data'
    waveobj.solvefwd()
    myplot.plot_timeseries(waveobj.solfwd, 'pd', 0, skip, fctV)
    dd = waveobj.Bp.copy()
    # gradient
    print 'generate observations'
    waveobj.dd = dd
    waveobj.update_m(lambda_init_fn)
    waveobj.solvefwd_cost()
    cost1 = waveobj.misfit
    print 'misfit = {}'.format(waveobj.misfit)
    myplot.plot_timeseries(waveobj.solfwd, 'p', 0, skip, fctV)
    # Plot data and observations
    fig = plt.figure()
    if len(obspts) > 9: fig.set_size_inches(20., 15.)
    for ii in range(len(obspts)):
        if len(obspts) == 4: ax = fig.add_subplot(2, 2, ii + 1)
        else: ax = fig.add_subplot(4, 6, ii + 1)
        ax.plot(waveobj.PDE.times, waveobj.dd[ii, :], 'k--')
        ax.plot(waveobj.PDE.times, waveobj.Bp[ii, :], 'b')
        ax.set_title('Plot' + str(ii))
    fig.savefig(filename + '/observations.eps')
    print 'compute gradient'
    waveobj.solveadj_constructgrad()
    myplot.plot_timeseries(waveobj.soladj, 'v', 0, skip, fctV)
    MG = waveobj.MGv.array().copy()
    myplot.set_varname('grad')
    myplot.plot_vtk(waveobj.Grad)
    """
Exemplo n.º 3
0
# check regularizations are the same
regt = regulab.costab(at,bt)
reg0 = regulab.costab(a0,b0)
regta = regula.cost(at)
reg0a = regula.cost(a0)
if mpirank == 0:
    print 'Regularization at target={:.2e}, at initial state={:.2e} [ab]'.format(\
    regt, reg0)
    print 'Regularization at target={:.2e}, at initial state={:.2e} [a]'.format(\
    regta, reg0a)

# check gradients are the same
evaluationpoint = {'a':at, 'b':bt}
waveobjab.update_PDE(evaluationpoint)
waveobjab.solvefwd_cost()
waveobjab.solveadj_constructgrad()
MGa, MGb = waveobjab.MG.split(deepcopy=True)
MGanorm = MGa.vector().norm('l2')
MGbnorm = MGb.vector().norm('l2')
if mpirank == 0:
    print '|MGa|={}, |MGb|={}'.format(MGanorm, MGbnorm)

waveobjabnoregul.update_PDE(evaluationpoint)
waveobjabnoregul.solvefwd_cost()
waveobjabnoregul.solveadj_constructgrad()
MGaa, MGba = waveobjabnoregul.MG.split(deepcopy=True)
MGaa.vector().axpy(1.0, regula.grad(evaluationpoint['a']))
diffa = MGa.vector() - MGaa.vector()
diffb = MGb.vector() - MGba.vector()
MGaanorm = MGaa.vector().norm('l2')
MGbanorm = MGba.vector().norm('l2')
def run_test(fpeak, lambdamin, lambdamax, Nxy, tfilterpts, r, Dt, skip):
    h = 1./Nxy
    checkdt(Dt, h, r, np.sqrt(lambdamax), True)
    mesh = dl.UnitSquareMesh(Nxy, Nxy)
    Vl = dl.FunctionSpace(mesh, 'Lagrange', 1)
    V = dl.FunctionSpace(mesh, 'Lagrange', r)
    fctV = dl.Function(V)
    # set up plots:
    filename, ext = splitext(sys.argv[0])
    if isdir(filename + '/'):   rmtree(filename + '/')
    myplot = PlotFenics(filename)
    # source:
    Ricker = RickerWavelet(fpeak, 1e-10)
    Pt = PointSources(V, [[0.5,0.5]])
    mydelta = Pt[0].array()
    def mysrc(tt):
        return Ricker(tt)*mydelta
    # target medium:
    lambda_target = dl.Expression('lmin + x[0]*(lmax-lmin)', \
    lmin=lambdamin, lmax=lambdamax)
    lambda_target_fn = dl.interpolate(lambda_target, Vl)
    myplot.set_varname('lambda_target')
    myplot.plot_vtk(lambda_target_fn)
    # initial medium:
    lambda_init = dl.Constant(lambdamin)
    lambda_init_fn = dl.interpolate(lambda_init, Vl)
    myplot.set_varname('lambda_init')
    myplot.plot_vtk(lambda_init_fn)
    # observation operator:
    #obspts = [[0.2, 0.5], [0.5, 0.2], [0.5, 0.8], [0.8, 0.5]]
    obspts = [[0.2, ii/10.] for ii in range(2,9)] + \
    [[0.8, ii/10.] for ii in range(2,9)] + \
    [[ii/10., 0.2] for ii in range(3,8)] + \
    [[ii/10., 0.8] for ii in range(3,8)]
    obsop = TimeObsPtwise({'V':V, 'Points':obspts}, tfilterpts)
    # define pde operator:
    wavepde = AcousticWave({'V':V, 'Vl':Vl, 'Vr':Vl})
    wavepde.timestepper = 'centered'
    wavepde.lump = True
    wavepde.set_abc(mesh, LeftRight(), True)
    wavepde.update({'lambda':lambda_target_fn, 'rho':1.0, \
    't0':t0, 'tf':tf, 'Dt':Dt, 'u0init':dl.Function(V), 'utinit':dl.Function(V)})
    wavepde.ftime = mysrc
    # define objective function:
    waveobj = ObjectiveAcoustic(wavepde)
    waveobj.obsop = obsop
    # data
    print 'generate noisy data'
    waveobj.solvefwd()
    myplot.plot_timeseries(waveobj.solfwd, 'pd', 0, skip, fctV)
    dd = waveobj.Bp.copy()
    nbobspt, dimsol = dd.shape
    noiselevel = 0.1   # = 10%
    sigmas = np.sqrt((dd**2).sum(axis=1)/dimsol)*noiselevel
    rndnoise = np.random.randn(nbobspt*dimsol).reshape((nbobspt, dimsol))
    waveobj.dd = dd + sigmas.reshape((len(sigmas),1))*rndnoise
    # gradient
    print 'generate observations'
    waveobj.update_m(lambda_init_fn)
    waveobj.solvefwd_cost()
    cost1 = waveobj.misfit
    print 'misfit = {}'.format(waveobj.misfit)
    myplot.plot_timeseries(waveobj.solfwd, 'p', 0, skip, fctV)
    # Plot data and observations
    fig = plt.figure()
    if len(obspts) > 9: fig.set_size_inches(20., 15.)
    for ii in range(len(obspts)):
        if len(obspts) == 4:    ax = fig.add_subplot(2,2,ii+1)
        else:   ax = fig.add_subplot(4,6,ii+1)
        ax.plot(waveobj.PDE.times, waveobj.dd[ii,:], 'k--')
        ax.plot(waveobj.PDE.times, waveobj.Bp[ii,:], 'b')
        ax.set_title('Plot'+str(ii))
    fig.savefig(filename + '/observations.eps')
    print 'compute gradient'
    waveobj.solveadj_constructgrad()
    myplot.plot_timeseries(waveobj.soladj, 'v', 0, skip, fctV)
    MG = waveobj.MGv.array().copy()
    myplot.set_varname('grad')
    myplot.plot_vtk(waveobj.Grad)
    print 'check gradient with FD'
    Medium = np.zeros((5, Vl.dim()))
    for ii in range(5):
        smoothperturb = dl.Expression('sin(n*pi*x[0])*sin(n*pi*x[1])', n=ii+1)
        smoothperturb_fn = dl.interpolate(smoothperturb, Vl)
        Medium[ii,:] = smoothperturb_fn.vector().array()
    checkgradfd_med(waveobj, Medium, 1e-6, [1e-5, 1e-4])
    print 'check Hessian with FD'
    checkhessfd_med(waveobj, Medium, 1e-6, [1e-1, 1e-2, 1e-3, 1e-4, 1e-5], False)