V = FunctionSpace(mesh, 'Lagrange', r)
    Pt = PointSources(V, [[.5,.5]])
    mydelta = Pt[0].array()
    def mysrc(tt):
        return Ricker(tt)*mydelta
    # Computation:
    if myrank == 0: print '\n\th = {}, Dt = {}'.format(h, Dt)
    Wave = AcousticWave({'V':V, 'Vl':Vl, 'Vr':Vl})
    #Wave.verbose = True
    Wave.timestepper = 'centered'
    Wave.lump = True
    Wave.set_abc(mesh, AllFour(), True)
    Wave.exact = Function(V)
    Wave.update({'lambda':1.0, 'rho':1.0, 't0':0.0, 'tf':tf, 'Dt':Dt,\
    'u0init':Function(V), 'utinit':Function(V)})
    Wave.ftime = mysrc
    sol, error = Wave.solve()
    ERROR.append(error)
    if myrank == 0: print 'relative error = {:.5e}'.format(error)
    if not mycomm == None:  MPI.barrier(mycomm)

# Plots:
try:
    boolplot = int(sys.argv[1])
except:
    boolplot = 0
if boolplot > 0:
    filename, ext = splitext(sys.argv[0])
    if myrank == 0: 
        if isdir(filename + '/'):   rmtree(filename + '/')
    if not mycomm == None:  MPI.barrier(mycomm)
    V = FunctionSpace(mesh, 'Lagrange', q)
    Dt = h/(q*5.*c)

    Wave = AcousticWave({'V':V, 'Vl':V, 'Vr':V})
    Wave.timestepper = 'backward'
    Wave.lump = True
    #Wave.verbose = True
    Wave.exact = interpolate(exact_expr, V)
    Wave.update({'lambda':lam, 'rho':rho, 't0':0.0, 'tf':tf, 'Dt':Dt,\
    'u0init':Function(V), 'utinit':Function(V)})
    test = TestFunction(V)
    def srcterm(tt):
        src_expr = source(tt)
        src_vect = assemble(src_expr*test*dx)
        return src_vect.array()
    Wave.ftime = srcterm
    sol, error = Wave.solve()
    ERROR.append(error)
    print 'relative error = {:.5e}'.format(error)

# Convergence order:
CONVORDER = []
for ii in range(len(ERROR)-1):
    CONVORDER.append(np.log(ERROR[ii+1]/ERROR[ii])/np.log((1./NN[ii+1])/(1./NN[ii])))
print '\n\norder of convergence:', CONVORDER

# Save plots:
try:
    boolplot = int(sys.argv[1])
except:
    boolplot = 0
    mydelta = Pt[0].array()

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

    # Computation:
    if myrank == 0: print '\n\th = {}, Dt = {}'.format(h, Dt)
    Wave = AcousticWave({'V': V, 'Vm': Vl})
    #Wave.verbose = True
    Wave.timestepper = 'centered'
    Wave.lump = True
    Wave.set_abc(mesh, AllFour(), True)
    Wave.exact = Function(V)
    Wave.update({'b':1.0, 'a':1.0, 't0':0.0, 'tf':tf, 'Dt':Dt,\
    'u0init':Function(V), 'utinit':Function(V)})
    Wave.ftime = mysrc
    sol, error = Wave.solve()
    ERROR.append(error)
    if myrank == 0: print 'relative error = {:.5e}'.format(error)
    if not mycomm == None: MPI.barrier(mycomm)

# Plots:
try:
    boolplot = int(sys.argv[1])
except:
    boolplot = 0
if boolplot > 0:
    filename, ext = splitext(sys.argv[0])
    if myrank == 0:
        if isdir(filename + '/'): rmtree(filename + '/')
    if not mycomm == None: MPI.barrier(mycomm)
Vl = dl.FunctionSpace(mesh, 'Lagrange', 1)
Vex = dl.FunctionSpace(mesh, 'Lagrange', r)
Pt = PointSources(Vex, [[.5, .5]])
mydelta = Pt[0].array()


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


Waveex = AcousticWave({'V': Vex, 'Vm': Vl})
Waveex.timestepper = 'backward'
Waveex.lump = True
Waveex.update({'a':1.0, 'b':1.0, 't0':0.0, 'tf':tf, 'Dt':Dt,\
'u0init':dl.Function(Vex), 'utinit':dl.Function(Vex)})
Waveex.ftime = mysrc
sol, _ = Waveex.solve()
Waveex.exact = dl.Function(Vex)
normex = Waveex.computeabserror()
# plot
myplot.set_varname('u-q' + str(qq))
plotu = dl.Function(Vex)
for index, uu in enumerate(sol):
    if index % boolplot == 0:
        setfct(plotu, uu[0])
        myplot.plot_vtk(plotu, index)
myplot.gather_vtkplots()

print 'Check different spatial sampling'
QQ = [4, 5, 6, 10]
for qq in QQ:
# PerturbationMedExpr = dl.Expression(medformula, A=1.0)
# PerturbMed = dl.interpolate(PerturbationMedExpr, Vl)
# myplot.set_varname('perturb_medium')
# myplot.plot_vtk(PerturbMed)
# observation operator:
obspts = [[x / 10.0, 1.0] for x in range(1, 10)]
obsop = TimeObsPtwise({"V": V, "Points": obspts})
# define pde operator:
wavepde = AcousticWave({"V": V, "Vl": Vl, "Vr": Vl})
wavepde.timestepper = "backward"
wavepde.lump = True
wavepde.set_abc(mesh, ABC(), True)
wavepde.update(
    {"lambda": TargetMed, "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, 40, fctV)
dd = waveobj.Bp.copy()
waveobj.dd = dd

# Plot observations
# fig = plt.figure()
# for ii in range(len(obspts)):
#    ax = fig.add_subplot(3,3,ii+1)
#    ax.plot(waveobj.times, waveobj.dd[ii,:], 'k--')
    h = 1./Nxy
    mesh = UnitSquareMesh(Nxy, Nxy)
    V = FunctionSpace(mesh, 'Lagrange', q)
    Vl = FunctionSpace(mesh, 'Lagrange', 1)
    Dt = h/(q*alpha*c)
    if myrank == 0: print '\n\th = {}, Dt = {}'.format(h, Dt)

    Wave = AcousticWave({'V':V, 'Vl':Vl, 'Vr':Vl})
    #Wave.verbose = True
    Wave.timestepper = 'centered'
    Wave.lump = True
    Wave.set_abc(mesh, LeftRight(), True)
    Wave.exact = interpolate(exact_expr, V)
    Wave.update({'lambda':lam, 'rho':rho, 't0':0.0, 'tf':tf, 'Dt':Dt,\
    'u0init':interpolate(u0_expr, V), 'utinit':Function(V)})
    Wave.ftime = lambda t: 0.0
    sol, error = Wave.solve()
    ERROR.append(error)
    if myrank == 0: print 'relative error = {:.5e}'.format(error)
    if not mycomm == None:  MPI.barrier(mycomm)

if myrank == 0:
    # Order of convergence:
    CONVORDER = []
    for ii in range(len(ERROR)-1):
        CONVORDER.append(np.log(ERROR[ii+1]/ERROR[ii])/np.log((1./NN[ii+1])/(1./NN[ii])))
    print '\n\norder of convergence:', CONVORDER

# Save plots:
try:
    boolplot = int(sys.argv[1])
Beispiel #7
0
    h = 1. / Nxy
    mesh = UnitSquareMesh(Nxy, Nxy)
    V = FunctionSpace(mesh, 'Lagrange', q)
    Vl = FunctionSpace(mesh, 'Lagrange', 1)
    Dt = h / (q * alpha * c)
    if myrank == 0: print '\n\th = {}, Dt = {}'.format(h, Dt)

    Wave = AcousticWave({'V': V, 'Vm': Vl})
    #Wave.verbose = True
    Wave.timestepper = 'centered'
    Wave.lump = True
    Wave.set_abc(mesh, LeftRight(), True)
    Wave.exact = interpolate(exact_expr, V)
    Wave.update({'b':b, 'a':a, 't0':0.0, 'tf':tf, 'Dt':Dt,\
    'u0init':interpolate(u0_expr, V), 'utinit':Function(V)})
    Wave.ftime = lambda t: 0.0
    sol, error = Wave.solve()
    ERROR.append(error)
    if myrank == 0: print 'relative error = {:.5e}'.format(error)
    if not mycomm == None: MPI.barrier(mycomm)

if myrank == 0:
    # Order of convergence:
    CONVORDER = []
    for ii in range(len(ERROR) - 1):
        CONVORDER.append(
            np.log(ERROR[ii + 1] / ERROR[ii]) / np.log(
                (1. / NN[ii + 1]) / (1. / NN[ii])))
    print '\n\norder of convergence:', CONVORDER

# Save plots:
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)
    """
qq = 20
N = int(qq/cmin)
h = 1./N
mesh = dl.UnitSquareMesh(N,N)
Vl = dl.FunctionSpace(mesh, 'Lagrange', 1)
Vex = dl.FunctionSpace(mesh, 'Lagrange', r)
Pt = PointSources(Vex, [[.5,.5]])
mydelta = Pt[0].array()
def mysrc(tt):
    return Ricker(tt)*mydelta
Waveex = AcousticWave({'V':Vex, 'Vl':Vl, 'Vr':Vl})
Waveex.timestepper = 'backward'
Waveex.lump = True
Waveex.update({'lambda':1.0, 'rho':1.0, 't0':0.0, 'tf':tf, 'Dt':Dt,\
'u0init':dl.Function(Vex), 'utinit':dl.Function(Vex)})
Waveex.ftime = mysrc
sol,_ = Waveex.solve()
Waveex.exact = dl.Function(Vex)
normex = Waveex.computeabserror()
# plot
myplot.set_varname('u-q'+str(qq))
plotu = dl.Function(Vex)
for index, uu in enumerate(sol):
    if index%boolplot == 0:
        setfct(plotu, uu[0])
        myplot.plot_vtk(plotu, index)
myplot.gather_vtkplots()

print 'Check different spatial sampling'
QQ = [4, 5, 6, 10]
for qq in QQ:
    print '\n\th = {}'.format(h)
    mesh = UnitSquareMesh(Nxy, Nxy, "crossed")
    q = 1   # This example is solved 'exactly' for q>=2
    V = FunctionSpace(mesh, 'Lagrange', q)
    Dt = h/(q*5.*np.sqrt(c2))

    Wave = AcousticWave({'V':V, 'Vl':V, 'Vr':V})
    Wave.timestepper = 'backward'
    Wave.lump = True
    Wave.exact = interpolate(exact_expr, V)
    Wave.bc = DirichletBC(V, ubc, u0_boundary)
    Wave.update({'lambda':lam, 'rho':rho, 't0':0.0, 'tf':tf, 'Dt':Dt,\
    'u0init':Function(V), 'utinit':interpolate(utinit_expr, V)})
    test = TestFunction(V)
    source = assemble(Constant('2')*test*dx)
    Wave.ftime = lambda tt: tt*source.array()
    sol, error = Wave.solve()
    ERROR.append(error)
    print 'relative error = {:.5e}'.format(error)

# Convergence order:
CONVORDER = []
for ii in range(len(ERROR)-1):
    CONVORDER.append(np.log(ERROR[ii+1]/ERROR[ii])/np.log((1./NN[ii+1])/(1./NN[ii])))
print '\n\norder of convergence:', CONVORDER

# Save plots:
try:
    boolplot = int(sys.argv[1])
except:
    boolplot = 0
Beispiel #11
0
    Wave = AcousticWave({'V': V, 'Vl': V, 'Vr': V})
    Wave.timestepper = 'backward'
    Wave.lump = True
    #Wave.verbose = True
    Wave.exact = interpolate(exact_expr, V)
    Wave.update({'lambda':lam, 'rho':rho, 't0':0.0, 'tf':tf, 'Dt':Dt,\
    'u0init':Function(V), 'utinit':Function(V)})
    test = TestFunction(V)

    def srcterm(tt):
        src_expr = source(tt)
        src_vect = assemble(src_expr * test * dx)
        return src_vect.array()

    Wave.ftime = srcterm
    sol, error = Wave.solve()
    ERROR.append(error)
    print 'relative error = {:.5e}'.format(error)

# Convergence order:
CONVORDER = []
for ii in range(len(ERROR) - 1):
    CONVORDER.append(
        np.log(ERROR[ii + 1] / ERROR[ii]) / np.log(
            (1. / NN[ii + 1]) / (1. / NN[ii])))
print '\n\norder of convergence:', CONVORDER

# Save plots:
try:
    boolplot = int(sys.argv[1])
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)
    print '\n\th = {}'.format(h)
    mesh = UnitSquareMesh(Nxy, Nxy, "crossed")
    q = 1  # This example is solved 'exactly' for q>=2
    V = FunctionSpace(mesh, 'Lagrange', q)
    Dt = h / (q * 5. * np.sqrt(c2))

    Wave = AcousticWave({'V': V, 'Vl': V, 'Vr': V})
    Wave.timestepper = 'backward'
    Wave.lump = True
    Wave.exact = interpolate(exact_expr, V)
    Wave.bc = DirichletBC(V, ubc, u0_boundary)
    Wave.update({'lambda':lam, 'rho':rho, 't0':0.0, 'tf':tf, 'Dt':Dt,\
    'u0init':Function(V), 'utinit':interpolate(utinit_expr, V)})
    test = TestFunction(V)
    source = assemble(Constant('2') * test * dx)
    Wave.ftime = lambda tt: tt * source.array()
    sol, error = Wave.solve()
    ERROR.append(error)
    print 'relative error = {:.5e}'.format(error)

# Convergence order:
CONVORDER = []
for ii in range(len(ERROR) - 1):
    CONVORDER.append(
        np.log(ERROR[ii + 1] / ERROR[ii]) / np.log(
            (1. / NN[ii + 1]) / (1. / NN[ii])))
print '\n\norder of convergence:', CONVORDER

# Save plots:
try:
    boolplot = int(sys.argv[1])