Beispiel #1
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def test_ScalarView_mpl_unknown():
    mesh = Mesh()
    mesh.load(domain_mesh)
    mesh.refine_element(0)
    shapeset = H1Shapeset()
    pss = PrecalcShapeset(shapeset)

    # create an H1 space
    space = H1Space(mesh, shapeset)
    space.set_uniform_order(5)
    space.assign_dofs()

    # initialize the discrete problem
    wf = WeakForm(1)
    set_forms(wf)

    solver = DummySolver()
    sys = LinSystem(wf, solver)
    sys.set_spaces(space)
    sys.set_pss(pss)

    # assemble the stiffness matrix and solve the system
    sys.assemble()
    A = sys.get_matrix()
    b = sys.get_rhs()
    from scipy.sparse.linalg import cg

    x, res = cg(A, b)
    sln = Solution()
    sln.set_fe_solution(space, pss, x)

    view = ScalarView("Solution")
Beispiel #2
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def test_example_03():
    set_verbose(False)

    mesh = Mesh()
    mesh.load(domain_mesh)
    mesh.refine_element(0)
    shapeset = H1Shapeset()
    pss = PrecalcShapeset(shapeset)

    # create an H1 space
    space = H1Space(mesh, shapeset)
    space.set_uniform_order(5)
    from hermes2d.examples.c03 import set_bc

    set_bc(space)
    space.assign_dofs()

    # initialize the discrete problem
    wf = WeakForm(1)
    set_forms(wf)

    solver = DummySolver()
    sys = LinSystem(wf, solver)
    sys.set_spaces(space)
    sys.set_pss(pss)

    # assemble the stiffness matrix and solve the system
    sln = Solution()
    sys.assemble()
    sys.solve_system(sln)
    assert abs(sln.l2_norm() - 0.25493) < 1e-4
    assert abs(sln.h1_norm() - 0.89534) < 1e-4
Beispiel #3
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def test_example_09():
    from hermes2d.examples.c09 import set_bc, temp_ext, set_forms

    # The following parameters can be changed:
    INIT_REF_NUM = 4      # number of initial uniform mesh refinements
    INIT_REF_NUM_BDY = 1  # number of initial uniform mesh refinements towards the boundary
    P_INIT = 4            # polynomial degree of all mesh elements
    TAU = 300.0           # time step in seconds

    # Problem constants
    T_INIT = 10           # temperature of the ground (also initial temperature)
    FINAL_TIME = 86400    # length of time interval (24 hours) in seconds

    # Global variable
    TIME = 0;

    # Boundary markers.
    bdy_ground = 1
    bdy_air = 2

    # Load the mesh
    mesh = Mesh()
    mesh.load(get_cathedral_mesh())

    # Perform initial mesh refinements
    for i in range(INIT_REF_NUM):
        mesh.refine_all_elements()
    mesh.refine_towards_boundary(bdy_air, INIT_REF_NUM_BDY)

    # Create an H1 space with default shapeset
    space = H1Space(mesh, P_INIT)
    set_bc(space)

    # Set initial condition
    tsln = Solution()
    tsln.set_const(mesh, T_INIT)

    # Initialize the weak formulation
    wf = WeakForm()
    set_forms(wf)

    # Initialize the linear system.
    ls = LinSystem(wf)
    ls.set_spaces(space)

    # Time stepping
    nsteps = int(FINAL_TIME/TAU + 0.5)
    rhsonly = False;

    # Assemble and solve
    ls.assemble()
    rhsonly = True
    ls.solve_system(tsln, lib="scipy")
Beispiel #4
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def test_fe_solutions():
    mesh = Mesh()
    mesh.load(domain_mesh)
    shapeset = H1Shapeset()
    pss = PrecalcShapeset(shapeset)

    space = H1Space(mesh, shapeset)
    space.set_uniform_order(2)
    space.assign_dofs()

    a = array([1, 2, 3, 8, 0.1])

    sln = Solution()
    sln.set_fe_solution(space, pss, a)
Beispiel #5
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def test_fe_solutions():
    mesh = Mesh()
    mesh.load(domain_mesh)

    space = H1Space(mesh, 1)
    space.set_uniform_order(2)
    space.assign_dofs()

    a = array([1, 2, 3, 8, 0.1])

    sln = Solution()
Beispiel #6
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def test_example_04():
    from hermes2d.examples.c04 import set_bc

    set_verbose(False)

    mesh = Mesh()
    mesh.load(domain_mesh)
    # mesh.refine_element(0)
    # mesh.refine_all_elements()
    mesh.refine_towards_boundary(5, 3)
    shapeset = H1Shapeset()
    pss = PrecalcShapeset(shapeset)

    # create an H1 space
    space = H1Space(mesh, shapeset)
    space.set_uniform_order(5)

    set_bc(space)

    space.assign_dofs()

    xprev = Solution()
    yprev = Solution()

    # initialize the discrete problem
    wf = WeakForm()
    set_forms(wf, -4)

    solver = DummySolver()
    sys = LinSystem(wf, solver)
    sys.set_spaces(space)
    sys.set_pss(pss)

    # assemble the stiffness matrix and solve the system
    sys.assemble()
    sln = Solution()
    sys.solve_system(sln)
    assert abs(sln.l2_norm() - 1.22729) < 1e-4
    assert abs(sln.h1_norm() - 2.90006) < 1e-4
Beispiel #7
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def test_example_05():
    from hermes2d.examples.c05 import set_bc
    from hermes2d.examples.c05 import set_forms as set_forms_surf

    set_verbose(False)

    mesh = Mesh()
    mesh.load(domain_mesh)
    mesh.refine_towards_vertex(3, 12)
    shapeset = H1Shapeset()
    pss = PrecalcShapeset(shapeset)

    # create an H1 space
    space = H1Space(mesh, shapeset)
    space.set_uniform_order(4)

    set_bc(space)

    space.assign_dofs()

    xprev = Solution()
    yprev = Solution()

    # initialize the discrete problem
    wf = WeakForm(1)
    set_forms(wf, -1)
    set_forms_surf(wf)

    sln = Solution()
    solver = DummySolver()
    sys = LinSystem(wf, solver)
    sys.set_spaces(space)
    sys.set_pss(pss)
    sys.assemble()
    sys.solve_system(sln)
    assert abs(sln.l2_norm() - 0.535833) < 1e-4
    assert abs(sln.h1_norm() - 1.332908) < 1e-4
def poisson_solver(mesh_tuple):
    """
    Poisson solver.

    mesh_tuple ... a tuple of (nodes, elements, boundary, nurbs)
    """
    set_verbose(False)
    mesh = Mesh()
    mesh.create(*mesh_tuple)
    mesh.refine_element(0)
    shapeset = H1Shapeset()
    pss = PrecalcShapeset(shapeset)

    # create an H1 space
    space = H1Space(mesh, shapeset)
    space.set_uniform_order(5)
    space.assign_dofs()

    # initialize the discrete problem
    wf = WeakForm(1)
    set_forms(wf)

    solver = DummySolver()
    sys = LinSystem(wf, solver)
    sys.set_spaces(space)
    sys.set_pss(pss)

    # assemble the stiffness matrix and solve the system
    sys.assemble()
    A = sys.get_matrix()
    b = sys.get_rhs()
    from scipy.sparse.linalg import cg
    x, res = cg(A, b)
    sln = Solution()
    sln.set_fe_solution(space, pss, x)
    return sln
Beispiel #9
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def test_example_08():
    from hermes2d.examples.c08 import set_bc, set_forms

    set_verbose(False)

    mesh = Mesh()
    mesh.load(cylinder_mesh)
    #mesh.refine_element(0)
    #mesh.refine_all_elements()
    mesh.refine_towards_boundary(5, 3)
    shapeset = H1Shapeset()
    pss = PrecalcShapeset(shapeset)

    # create an H1 space
    xvel = H1Space(mesh, shapeset)
    yvel = H1Space(mesh, shapeset)
    press = H1Space(mesh, shapeset)
    xvel.set_uniform_order(2)
    yvel.set_uniform_order(2)
    press.set_uniform_order(1)

    set_bc(xvel, yvel, press)

    ndofs = 0
    ndofs += xvel.assign_dofs(ndofs)
    ndofs += yvel.assign_dofs(ndofs)
    ndofs += press.assign_dofs(ndofs)

    xprev = Solution()
    yprev = Solution()

    xprev.set_zero(mesh)
    yprev.set_zero(mesh)

    # initialize the discrete problem
    wf = WeakForm(3)
    set_forms(wf, xprev, yprev)

    solver = DummySolver()
    sys = LinSystem(wf, solver)
    sys.set_spaces(xvel, yvel, press)
    sys.set_pss(pss)
    #dp.set_external_fns(xprev, yprev)

    # visualize the solution

    EPS_LOW = 0.0014

    for i in range(3):
        psln = Solution()
        sys.assemble()
        sys.solve_system(xprev, yprev, psln)
Beispiel #10
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def test_example_06():
    from hermes2d.examples.c06 import set_bc, set_forms

    set_verbose(False)

    # The following parameters can be changed:

    UNIFORM_REF_LEVEL = 2
    # Number of initial uniform mesh refinements.
    CORNER_REF_LEVEL = 12
    # Number of mesh refinements towards the re-entrant corner.
    P_INIT = 6
    # Uniform polynomial degree of all mesh elements.

    # Boundary markers
    NEWTON_BDY = 1

    # Load the mesh file
    mesh = Mesh()
    mesh.load(get_example_mesh())

    # Perform initial mesh refinements.
    for i in range(UNIFORM_REF_LEVEL):
        mesh.refine_all_elements()
    mesh.refine_towards_vertex(3, CORNER_REF_LEVEL)

    # Create an H1 space with default shapeset
    space = H1Space(mesh, P_INIT)
    set_bc(space)

    # Initialize the weak formulation
    wf = WeakForm()
    set_forms(wf)

    # Initialize the linear system.
    ls = LinSystem(wf)
    ls.set_spaces(space)

    # Assemble and solve the matrix problem
    sln = Solution()
    ls.assemble()
    ls.solve_system(sln)
Beispiel #11
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def test_matrix():
    set_verbose(False)

    mesh = Mesh()
    mesh.load(domain_mesh)
    mesh.refine_element_id(0)

    # create an H1 space with default shapeset
    space = H1Space(mesh, 1)

    # initialize the discrete problem
    wf = WeakForm(1)
    set_forms(wf)

    sys = LinSystem(wf)
    sys.set_spaces(space)

    # assemble the stiffness matrix and solve the system
    sln = Solution()
    sys.assemble()
    A = sys.get_matrix()
Beispiel #12
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# create an H1 space
space = H1Space(mesh, shapeset)
space.set_uniform_order(5)
space.assign_dofs()

# initialize the discrete problem
wf = WeakForm(1)
set_forms(wf)

solver = DummySolver()
sys = LinSystem(wf, solver)
sys.set_spaces(space)
sys.set_pss(pss)

# assemble the stiffness matrix and solve the system
sys.assemble()
A = sys.get_matrix()
b = sys.get_rhs()
from scipy.sparse.linalg import cg
x, res = cg(A, b)
sln = Solution()
sln.set_fe_solution(space, pss, x)

view = ScalarView("Solution")
view.show(sln, lib="mayavi")
# view.wait()

mview = MeshView("Hello world!", 100, 100, 500, 500)
mview.show(mesh, lib="mpl", method="orders", notebook=False)
mview.wait()
Beispiel #13
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# Load the mesh
mesh = Mesh()
mesh.load(get_cathedral_mesh())

# Perform initial mesh refinements
for i in range(INIT_REF_NUM):
    mesh.refine_all_elements()
mesh.refine_towards_boundary(bdy_air, INIT_REF_NUM_BDY)

# Create an H1 space with default shapeset
space = H1Space(mesh, P_INIT)
set_bc(space)

# Set initial condition
tsln = Solution()
tsln.set_const(mesh, T_INIT)

# Initialize the weak formulation
wf = WeakForm()
set_forms(wf)

# Initialize the linear system.
ls = LinSystem(wf)
ls.set_spaces(space)

# Visualisation
sview = ScalarView("Temperature", 0, 0, 450, 600)
#title = "Time %s, exterior temperature %s" % (TIME, temp_ext(TIME))
#Tview.set_min_max_range(0,20);
#Tview.set_title(title);
Beispiel #14
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 def minus(sols, i):
     sln = Solution()
     vec = sols[:, i]
     sln.set_fe_solution(rspace, pss, -vec)
     return sln
Beispiel #15
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mesh = Mesh()
mesh.load(get_example_mesh())

# Perform initial mesh refinements.
for i in range(UNIFORM_REF_LEVEL):
    mesh.refine_all_elements()
mesh.refine_towards_vertex(3, CORNER_REF_LEVEL)

# Create an H1 space with default shapeset
space = H1Space(mesh, P_INIT)
set_bc(space)

# Initialize the weak formulation
wf = WeakForm()
set_forms(wf)

# Initialize the linear system.
ls = LinSystem(wf)
ls.set_spaces(space)

# Assemble and solve the matrix problem
sln = Solution()
ls.assemble()
ls.solve_system(sln)

# Visualize the approximation
sln.plot()

# Visualize the mesh
mesh.plot(space=space)
Beispiel #16
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    def calc(threshold=0.3,
             strategy=0,
             h_only=False,
             error_tol=1,
             interactive_plotting=False,
             show_mesh=False,
             show_graph=True):
        mesh = Mesh()
        mesh.create([
            [0, 0],
            [1, 0],
            [1, 1],
            [0, 1],
        ], [
            [2, 3, 0, 1, 0],
        ], [
            [0, 1, 1],
            [1, 2, 1],
            [2, 3, 1],
            [3, 0, 1],
        ], [])

        mesh.refine_all_elements()

        shapeset = H1Shapeset()
        pss = PrecalcShapeset(shapeset)

        space = H1Space(mesh, shapeset)
        set_bc(space)
        space.set_uniform_order(1)

        wf = WeakForm(1)
        set_forms(wf)

        sln = Solution()
        rsln = Solution()
        solver = DummySolver()

        selector = H1ProjBasedSelector(CandList.HP_ANISO, 1.0, -1, shapeset)

        view = ScalarView("Solution")
        iter = 0
        graph = []
        while 1:
            space.assign_dofs()

            sys = LinSystem(wf, solver)
            sys.set_spaces(space)
            sys.set_pss(pss)
            sys.assemble()
            sys.solve_system(sln)
            dofs = sys.get_matrix().shape[0]
            if interactive_plotting:
                view.show(sln,
                          lib=lib,
                          notebook=True,
                          filename="a%02d.png" % iter)

            rsys = RefSystem(sys)
            rsys.assemble()

            rsys.solve_system(rsln)

            hp = H1Adapt([space])
            hp.set_solutions([sln], [rsln])
            err_est = hp.calc_error() * 100

            err_est = hp.calc_error(sln, rsln) * 100
            print "iter=%02d, err_est=%5.2f%%, DOFS=%d" % (iter, err_est, dofs)
            graph.append([dofs, err_est])
            if err_est < error_tol:
                break
            hp.adapt(selector, threshold, strategy)
            iter += 1

        if not interactive_plotting:
            view.show(sln, lib=lib, notebook=True)

        if show_mesh:
            mview = MeshView("Mesh")
            mview.show(mesh, lib="mpl", notebook=True, filename="b.png")

        if show_graph:
            from numpy import array
            graph = array(graph)
            import pylab
            pylab.clf()
            pylab.plot(graph[:, 0], graph[:, 1], "ko", label="error estimate")
            pylab.plot(graph[:, 0], graph[:, 1], "k-")
            pylab.title("Error Convergence for the Inner Layer Problem")
            pylab.legend()
            pylab.xlabel("Degrees of Freedom")
            pylab.ylabel("Error [%]")
            pylab.yscale("log")
            pylab.grid()
            pylab.savefig("graph.png")
Beispiel #17
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# Perform initial mesh refinements.
for i in range(INIT_REF_NUM):
    mesh.refine_all_elements()

# Create an H1 space with default shapeset
space = H1Space(mesh, P_INIT)
set_bc(space)

# Initialize the weak formulation
wf = WeakForm()
set_forms(wf)

# Initialize views
sview = ScalarView("Coarse solution", 0, 100, 798, 700)
oview = OrderView("Polynomial orders", 800, 100, 798, 700)

# Initialize the linear system.
ls = LinSystem(wf)
ls.set_spaces(space)

# Assemble and solve the matrix problem
sln = Solution()
ls.assemble()
ls.solve_system(sln)

# View the solution
sln.plot()

# View the mesh
mesh.plot(space=space)
Beispiel #18
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def test_example_11():
    from hermes2d.examples.c11 import set_bc, set_wf_forms, set_hp_forms

    SOLVE_ON_COARSE_MESH = True  # If true, coarse mesh FE problem is solved in every adaptivity step.
    P_INIT_U = 2  # Initial polynomial degree for u
    P_INIT_V = 2  # Initial polynomial degree for v
    INIT_REF_BDY = 3  # Number of initial boundary refinements
    MULTI = True  # MULTI = true  ... use multi-mesh,
    # MULTI = false ... use single-mesh.
    # Note: In the single mesh option, the meshes are
    # forced to be geometrically the same but the
    # polynomial degrees can still vary.
    THRESHOLD = 0.3  # This is a quantitative parameter of the adapt(...) function and
    # it has different meanings for various adaptive strategies (see below).
    STRATEGY = 1  # Adaptive strategy:
    # STRATEGY = 0 ... refine elements until sqrt(THRESHOLD) times total
    #   error is processed. If more elements have similar errors, refine
    #   all to keep the mesh symmetric.
    # STRATEGY = 1 ... refine all elements whose error is larger
    #   than THRESHOLD times maximum element error.
    # STRATEGY = 2 ... refine all elements whose error is larger
    #   than THRESHOLD.
    # More adaptive strategies can be created in adapt_ortho_h1.cpp.

    CAND_LIST = CandList.H2D_HP_ANISO  # Predefined list of element refinement candidates.
    # Possible values are are attributes of the class CandList:
    # P_ISO, P_ANISO, H_ISO, H_ANISO, HP_ISO, HP_ANISO_H, HP_ANISO_P, HP_ANISO
    # See the Sphinx tutorial (http://hpfem.org/hermes2d/doc/src/tutorial-2.html#adaptive-h-fem-and-hp-fem) for details.

    MESH_REGULARITY = -1  # Maximum allowed level of hanging nodes:
    # MESH_REGULARITY = -1 ... arbitrary level hangning nodes (default),
    # MESH_REGULARITY = 1 ... at most one-level hanging nodes,
    # MESH_REGULARITY = 2 ... at most two-level hanging nodes, etc.
    # Note that regular meshes are not supported, this is due to
    # their notoriously bad performance.
    CONV_EXP = 1  # Default value is 1.0. This parameter influences the selection of
    # cancidates in hp-adaptivity. See get_optimal_refinement() for details.
    MAX_ORDER = 10  # Maximum allowed element degree
    ERR_STOP = 0.5  # Stopping criterion for adaptivity (rel. error tolerance between the
    # fine mesh and coarse mesh solution in percent).
    NDOF_STOP = 60000  # Adaptivity process stops when the number of degrees of freedom grows over
    # this limit. This is mainly to prevent h-adaptivity to go on forever.

    H2DRS_DEFAULT_ORDER = -1  # A default order. Used to indicate an unkonwn order or a maximum support order

    # Load the mesh
    umesh = Mesh()
    vmesh = Mesh()
    umesh.load(get_bracket_mesh())
    if MULTI == False:
        umesh.refine_towards_boundary(1, INIT_REF_BDY)

    # Create initial mesh (master mesh).
    vmesh.copy(umesh)

    # Initial mesh refinements in the vmesh towards the boundary
    if MULTI == True:
        vmesh.refine_towards_boundary(1, INIT_REF_BDY)

    # Create the x displacement space
    uspace = H1Space(umesh, P_INIT_U)
    vspace = H1Space(vmesh, P_INIT_V)

    # Initialize the weak formulation
    wf = WeakForm(2)
    set_wf_forms(wf)

    # Initialize refinement selector
    selector = H1ProjBasedSelector(CAND_LIST, CONV_EXP, H2DRS_DEFAULT_ORDER)

    # Initialize the coarse mesh problem
    ls = LinSystem(wf)
    ls.set_spaces(uspace, vspace)

    u_sln_coarse = Solution()
    v_sln_coarse = Solution()
    u_sln_fine = Solution()
    v_sln_fine = Solution()

    # Assemble and Solve the fine mesh problem
    rs = RefSystem(ls)
    rs.assemble()
    rs.solve_system(u_sln_fine, v_sln_fine, lib="scipy")

    # Either solve on coarse mesh or project the fine mesh solution
    # on the coarse mesh.
    if SOLVE_ON_COARSE_MESH:
        ls.assemble()
        ls.solve_system(u_sln_coarse, v_sln_coarse, lib="scipy")

    # Calculate element errors and total error estimate
    hp = H1Adapt(ls)
    hp.set_solutions([u_sln_coarse, v_sln_coarse], [u_sln_fine, v_sln_fine])
    set_hp_forms(hp)
    err_est = hp.calc_error() * 100
Beispiel #19
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# create an H1 space
xvel = H1Space(mesh, shapeset)
yvel = H1Space(mesh, shapeset)
press = H1Space(mesh, shapeset)
xvel.set_uniform_order(2)
yvel.set_uniform_order(2)
press.set_uniform_order(1)

set_bc(xvel, yvel, press)

ndofs = 0
ndofs += xvel.assign_dofs(ndofs)
ndofs += yvel.assign_dofs(ndofs)
ndofs += press.assign_dofs(ndofs)

xprev = Solution()
yprev = Solution()

xprev.set_zero(mesh)
yprev.set_zero(mesh)

# initialize the discrete problem
wf = WeakForm(3)
set_forms(wf, xprev, yprev)

# visualize the solution
vview = VectorView("velocity [m/s]", 0, 0, 1200, 350)
pview = ScalarView("pressure [Pa]", 0, 500, 1200, 350)
vview.set_min_max_range(0, 1.9)
vview.show_scale(False)
pview.show_scale(False)
Beispiel #20
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uoview = OrderView("Coarse mesh for u", 0, 0, 360, 300)
voview = OrderView("Coarse mesh for v", 370, 0, 360, 300)
uview = ScalarView("Coarse mesh solution u", 740, 0, 400, 300)
vview = ScalarView("Coarse mesh solution v", 1150, 0, 400, 300)

# Initialize refinement selector
selector = H1ProjBasedSelector(CAND_LIST, CONV_EXP, H2DRS_DEFAULT_ORDER)

# Initialize the coarse mesh problem
ls = LinSystem(wf)
ls.set_spaces(uspace, vspace)

# adaptivity loop
it = 1
done = False
u_sln_coarse = Solution()
v_sln_coarse = Solution()
u_sln_fine = Solution()
v_sln_fine = Solution()

while(not done):

    print ("\n---- Adaptivity step %d ---------------------------------------------\n" % it)
    it += 1
    
    # Assemble and Solve the fine mesh problem
    rs = RefSystem(ls)
    rs.assemble()
    rs.solve_system(u_sln_fine, v_sln_fine, lib="scipy")

    # Either solve on coarse mesh or project the fine mesh solution 
Beispiel #21
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def test_example_09():
    from hermes2d.examples.c09 import set_bc, temp_ext, set_forms

    # The following parameters can be played with:
    P_INIT = 1  # polynomial degree of elements
    INIT_REF_NUM = 4  # number of initial uniform refinements
    TAU = 300.0  # time step in seconds

    # Problem constants
    T_INIT = 10  # temperature of the ground (also initial temperature)
    FINAL_TIME = 86400  # length of time interval (24 hours) in seconds

    # Global variable
    TIME = 0

    # Load the mesh
    mesh = Mesh()
    mesh.load(get_cathedral_mesh())

    # for i in range(INIT_REF_NUM):
    #    mesh.refine_all_elements()
    # mesh.refine_towards_boundary(2, 5)

    # Set up shapeset
    shapeset = H1Shapeset()
    pss = PrecalcShapeset(shapeset)

    # Set up spaces
    space = H1Space(mesh, shapeset)
    set_bc(space)
    space.set_uniform_order(P_INIT)

    # Enumerate basis functions
    space.assign_dofs()

    # Set initial condition
    tsln = Solution()
    tsln.set_const(mesh, T_INIT)

    # Weak formulation
    wf = WeakForm(1)
    set_forms(wf, tsln)

    # Matrix solver
    solver = DummySolver()

    # Linear system
    ls = LinSystem(wf, solver)
    ls.set_spaces(space)
    ls.set_pss(pss)

    # Visualisation
    sview = ScalarView("Temperature", 0, 0, 450, 600)
    # title = "Time %s, exterior temperature %s" % (TIME, temp_ext(TIME))
    # Tview.set_min_max_range(0,20);
    # Tview.set_title(title);
    # Tview.fix_scale_width(3);

    # Time stepping
    nsteps = int(FINAL_TIME / TAU + 0.5)
    rhsonly = False

    # Assemble and solve
    ls.assemble()
    rhsonly = True
    ls.solve_system(tsln)
Beispiel #22
0
def test_example_22():
    from hermes2d.examples.c22 import set_bc, set_forms

    #  The following parameters can be changed:
    SOLVE_ON_COARSE_MESH = True  # if true, coarse mesh FE problem is solved in every adaptivity step
    INIT_REF_NUM = 1  # Number of initial uniform mesh refinements
    P_INIT = 2  # Initial polynomial degree of all mesh elements.
    THRESHOLD = 0.3  # This is a quantitative parameter of the adapt(...) function and
    # it has different meanings for various adaptive strategies (see below).
    STRATEGY = 0  # Adaptive strategy:
    # STRATEGY = 0 ... refine elements until sqrt(THRESHOLD) times total
    #   error is processed. If more elements have similar errors, refine
    #   all to keep the mesh symmetric.
    # STRATEGY = 1 ... refine all elements whose error is larger
    #   than THRESHOLD times maximum element error.
    # STRATEGY = 2 ... refine all elements whose error is larger
    #   than THRESHOLD.
    # More adaptive strategies can be created in adapt_ortho_h1.cpp.
    CAND_LIST = CandList.H2D_HP_ANISO  # Predefined list of element refinement candidates.
    # Possible values are are attributes of the class CandList:
    # P_ISO, P_ANISO, H_ISO, H_ANISO, HP_ISO, HP_ANISO_H, HP_ANISO_P, HP_ANISO
    # See the Sphinx tutorial (http://hpfem.org/hermes2d/doc/src/tutorial-2.html#adaptive-h-fem-and-hp-fem) for details.
    MESH_REGULARITY = -1  # Maximum allowed level of hanging nodes:
    # MESH_REGULARITY = -1 ... arbitrary level hangning nodes (default),
    # MESH_REGULARITY = 1 ... at most one-level hanging nodes,
    # MESH_REGULARITY = 2 ... at most two-level hanging nodes, etc.
    # Note that regular meshes are not supported, this is due to
    # their notoriously bad performance.
    CONV_EXP = 0.5
    ERR_STOP = 0.1  # Stopping criterion for adaptivity (rel. error tolerance between the
    # fine mesh and coarse mesh solution in percent).
    NDOF_STOP = 60000  # Adaptivity process stops when the number of degrees of freedom grows
    # over this limit. This is to prevent h-adaptivity to go on forever.

    H2DRS_DEFAULT_ORDER = -1  # A default order. Used to indicate an unkonwn order or a maximum support order

    # Problem parameters.
    SLOPE = 60  # Slope of the layer.

    # Load the mesh
    mesh = Mesh()
    mesh.create([
        [0, 0],
        [1, 0],
        [1, 1],
        [0, 1],
    ], [
        [2, 3, 0, 1, 0],
    ], [
        [0, 1, 1],
        [1, 2, 1],
        [2, 3, 1],
        [3, 0, 1],
    ], [])

    # Perform initial mesh refinements
    mesh.refine_all_elements()

    # Create an H1 space with default shapeset
    space = H1Space(mesh, P_INIT)
    set_bc(space)

    # Initialize the weak formulation
    wf = WeakForm()
    set_forms(wf)

    # Initialize refinement selector
    selector = H1ProjBasedSelector(CAND_LIST, CONV_EXP, H2DRS_DEFAULT_ORDER)

    # Initialize the coarse mesh problem
    ls = LinSystem(wf)
    ls.set_spaces(space)

    # Adaptivity loop
    iter = 0
    done = False
    sln_coarse = Solution()
    sln_fine = Solution()

    # Assemble and solve the fine mesh problem
    rs = RefSystem(ls)
    rs.assemble()
    rs.solve_system(sln_fine)

    # Either solve on coarse mesh or project the fine mesh solution
    # on the coarse mesh.
    if SOLVE_ON_COARSE_MESH:
        ls.assemble()
        ls.solve_system(sln_coarse)

    # Calculate error estimate wrt. fine mesh solution
    hp = H1Adapt(ls)
    hp.set_solutions([sln_coarse], [sln_fine])
    err_est = hp.calc_error() * 100
Beispiel #23
0
def schroedinger_solver(n_eigs=4, iter=2, verbose_level=1, plot=False,
        potential="hydrogen", report=False, report_filename="report.h5",
        force=False, sim_name="sim", potential2=None):
    """
    One particle Schroedinger equation solver.

    n_eigs ... the number of the lowest eigenvectors to calculate
    iter ... the number of adaptive iterations to do
    verbose_level ...
            0 ... quiet
            1 ... only moderate output (default)
            2 ... lot's of output
    plot ........ plot the progress (solutions, refined solutions, errors)
    potential ... the V(x) for which to solve, one of:
                    well, oscillator, hydrogen
    potential2 .. other terms that should be added to potential
    report ...... it will save raw data to a file, useful for creating graphs
                    etc.

    Returns the eigenvalues and eigenvectors.
    """
    set_verbose(verbose_level == 2)
    set_warn_integration(False)
    pot = {"well": 0, "oscillator": 1, "hydrogen": 2, "three-points": 3}
    pot_type = pot[potential]
    if report:
        from timeit import default_timer as clock
        from tables import IsDescription, UInt32Col, Float32Col, openFile, \
                Float64Col, Float64Atom, Col, ObjectAtom
        class Iteration(IsDescription):
            n = UInt32Col()
            DOF = UInt32Col()
            DOF_reference = UInt32Col()
            cpu_solve = Float32Col()
            cpu_solve_reference = Float32Col()
            eig_errors = Float64Col(shape=(n_eigs,))
            eigenvalues = Float64Col(shape=(n_eigs,))
            eigenvalues_reference = Float64Col(shape=(n_eigs,))
        h5file = openFile(report_filename, mode = "a",
                title = "Simulation data")
        if hasattr(h5file.root, sim_name):
            if force:
                h5file.removeNode(getattr(h5file.root, sim_name),
                        recursive=True)
            else:
                print "The group '%s' already exists. Use -f to overwrite it." \
                        % sim_name
                return
        group = h5file.createGroup("/", sim_name, 'Simulation run')
        table = h5file.createTable(group, "iterations", Iteration,
                "Iterations info")
        h5eigs = h5file.createVLArray(group, 'eigenvectors', ObjectAtom())
        h5eigs_ref = h5file.createVLArray(group, 'eigenvectors_reference',
                ObjectAtom())
        iteration = table.row

    mesh = Mesh()
    mesh.load("square.mesh")
    if potential == "well":
        # Read the width of the mesh automatically. This assumes there is just
        # one square element:
        a = sqrt(mesh.get_element(0).get_area())
        # set N high enough, so that we get enough analytical eigenvalues:
        N = 10
        levels = []
        for n1 in range(1, N):
            for n2 in range(1, N):
                levels.append(n1**2 + n2**2)
        levels.sort()

        E_exact = [pi**2/(2.*a**2) * m for m in levels]
    elif potential == "oscillator":
        E_exact = [1] + [2]*2 + [3]*3 + [4]*4 + [5]*5 + [6]*6
    elif potential == "hydrogen":
        Z = 1 # atom number
        E_exact = [-float(Z)**2/2/(n-0.5)**2/4 for n in [1]+[2]*3+[3]*5 +\
                                    [4]*8 + [5]*15]
    else:
        E_exact = [1.]*50
    if len(E_exact) < n_eigs:
        print n_eigs
        print E_exact
        raise Exception("We don't have enough analytical eigenvalues.")
    #mesh.refine_element(0)
    mesh.refine_all_elements()
    #mesh.refine_all_elements()
    #mesh.refine_all_elements()
    #mesh.refine_all_elements()

    #mview = MeshView()
    #mview.show(mesh)

    shapeset = H1Shapeset()
    space = H1Space(mesh, shapeset)
    space.set_uniform_order(2)
    space.assign_dofs()

    pss = PrecalcShapeset(shapeset)
    #bview = BaseView()
    #bview.show(space)

    wf1 = WeakForm(1)
    # this is induced by set_verbose():
    #dp1.set_quiet(not verbose)
    set_forms8(wf1, pot_type, potential2)
    wf2 = WeakForm(1)
    # this is induced by set_verbose():
    #dp2.set_quiet(not verbose)
    set_forms7(wf2)

    solver = DummySolver()

    w = 320
    h = 320
    views = [ScalarView("", i*w, 0, w, h) for i in range(4)]
    viewsm = [ScalarView("", i*w, h, w, h) for i in range(4)]
    viewse = [ScalarView("", i*w, 2*h, w, h) for i in range(4)]
    #for v in viewse:
    #    v.set_min_max_range(0, 10**-4)
    ord = OrderView("Polynomial Orders", 0, 2*h, w, h)

    rs = None

    precision = 30.0

    if verbose_level >= 1:
        print "Problem initialized. Starting calculation."

    for it in range(iter):
        if verbose_level >= 1:
            print "-"*80
            print "Starting iteration %d." % it
        if report:
            iteration["n"] = it

        #mesh.save("refined2.mesh")
        sys1 = LinSystem(wf1, solver)
        sys1.set_spaces(space)
        sys1.set_pss(pss)
        sys2 = LinSystem(wf2, solver)
        sys2.set_spaces(space)
        sys2.set_pss(pss)

        if verbose_level >= 1:
            print "Assembling the matrices A, B."
        sys1.assemble()
        sys2.assemble()
        if verbose_level == 2:
            print "converting matrices A, B"
        A = sys1.get_matrix()
        B = sys2.get_matrix()
        if verbose_level >= 1:
            n = A.shape[0]
            print "Solving the problem Ax=EBx  (%d x %d)." % (n, n)
        if report:
            n = A.shape[0]
            iteration["DOF"] = n
        if report:
            t = clock()
        eigs, sols = solve(A, B, n_eigs, verbose_level == 2)
        if report:
            t = clock() - t
            iteration["cpu_solve"] = t
            iteration["eigenvalues"] = array(eigs)
            #h5eigs.append(sols)
        if verbose_level >= 1:
            print "   \-Done."
            print_eigs(eigs, E_exact)
        s = []

        n = sols.shape[1]
        for i in range(n):
            sln = Solution()
            vec = sols[:, i]
            sln.set_fe_solution(space, pss, vec)
            s.append(sln)

        if verbose_level >= 1:
            print "Matching solutions."
        if rs is not None:
            def minus2(sols, i):
                sln = Solution()
                vec = sols[:, i]
                sln.set_fe_solution(space, pss, -vec)
                return sln
            pairs, flips = make_pairs(rs, s, d1, d2)
            #print "_"*40
            #print pairs, flips
            #print len(rs), len(s)
            #from time import sleep
            #sleep(3)
            #stop
            s2 = []
            for j, flip in zip(pairs, flips):
                if flip:
                    s2.append(minus2(sols,j))
                else:
                    s2.append(s[j])
            s = s2

        if plot:
            if verbose_level >= 1:
                print "plotting: solution"
            ord.show(space)
            for i in range(min(len(s), 4)):
                views[i].show(s[i])
                views[i].set_title("Iter: %d, eig: %d" % (it, i))
            #mat1.show(dp1)

        if verbose_level >= 1:
            print "reference: initializing mesh."

        rsys1 = RefSystem(sys1)
        rsys2 = RefSystem(sys2)
        if verbose_level >= 1:
            print "reference: assembling the matrices A, B."
        rsys1.assemble()
        rsys2.assemble()
        if verbose_level == 2:
            print "converting matrices A, B"
        A = rsys1.get_matrix()
        B = rsys2.get_matrix()
        if verbose_level >= 1:
            n = A.shape[0]
            print "reference: solving the problem Ax=EBx  (%d x %d)." % (n, n)
        if report:
            n = A.shape[0]
            iteration["DOF_reference"] = n
        if report:
            t = clock()
        eigs, sols = solve(A, B, n_eigs, verbose_level == 2)
        if report:
            t = clock() - t
            iteration["cpu_solve_reference"] = t
            iteration["eigenvalues_reference"] = array(eigs)
            #h5eigs_ref.append(sols)
        if verbose_level >= 1:
            print "   \-Done."
            print_eigs(eigs, E_exact)
        rs = []
        rspace = rsys1.get_ref_space(0)

        n = sols.shape[1]
        for i in range(n):
            sln = Solution()
            vec = sols[:, i]
            sln.set_fe_solution(rspace, pss, vec)
            rs.append(sln)

        if verbose_level >= 1:
            print "reference: matching solutions."
        def minus(sols, i):
            sln = Solution()
            vec = sols[:, i]
            sln.set_fe_solution(rspace, pss, -vec)
            return sln

        # segfaults
        #mat2.show(rp1)

        def d1(x, y):
            return (x-y).l2_norm()
        def d2(x, y):
            return (x+y).l2_norm()
        from pairs import make_pairs
        pairs, flips = make_pairs(s, rs, d1, d2)
        rs2 = []
        for j, flip in zip(pairs, flips):
            if flip:
                rs2.append(minus(sols,j))
            else:
                rs2.append(rs[j])
        rs = rs2

        if plot:
            if verbose_level >= 1:
                print "plotting: solution, reference solution, errors"
            for i in range(min(len(s), len(rs), 4)):
                #views[i].show(s[i])
                #views[i].set_title("Iter: %d, eig: %d" % (it, i))
                viewsm[i].show(rs[i])
                viewsm[i].set_title("Ref. Iter: %d, eig: %d" % (it, i))
                viewse[i].show((s[i]-rs[i])**2)
                viewse[i].set_title("Error plot Iter: %d, eig: %d" % (it, i))


        if verbose_level >= 1:
            print "Calculating errors."
        hp = H1OrthoHP(space)
        if verbose_level == 2:
            print "-"*60
            print "calc error (iter=%d):" % it
        eig_converging = 0
        errors = []
        for i in range(min(len(s), len(rs))):
            error = hp.calc_error(s[i], rs[i]) * 100
            errors.append(error)
            prec = precision
            if verbose_level >= 1:
                print "eig %d: %g%%  precision goal: %g%%" % (i, error, prec)
        if report:
            iteration["eig_errors"] = array(errors)
        if errors[0] > precision:
            eig_converging = 0
        elif errors[3] > precision:
            eig_converging = 3
        elif errors[1] > precision:
            eig_converging = 1
        elif errors[2] > precision:
            eig_converging = 2
        else:
            precision /= 2
        # uncomment the following line to only converge to some eigenvalue:
        #eig_converging = 3
        if verbose_level >= 1:
            print "picked: %d" % eig_converging
        error = hp.calc_error(s[eig_converging], rs[eig_converging]) * 100
        if verbose_level >= 1:
            print "Adapting the mesh."
        hp.adapt(0.3)
        space.assign_dofs()
        if report:
            iteration.append()
            table.flush()
    if report:
        h5file.close()
    return s
Beispiel #24
0
# Create the x- and y- displacement space using the default H1 shapeset
xdisp = H1Space(mesh, P_INIT)
ydisp = H1Space(mesh, P_INIT)
set_bc(xdisp, ydisp)

# Initialize the weak formulation
wf = WeakForm(2)
set_forms(wf)

# Initialize the linear system.
ls = LinSystem(wf)
ls.set_spaces(xdisp, ydisp)

# Assemble and solve the matrix problem
xsln = Solution()
ysln = Solution()
ls.assemble()
ls.solve_system(xsln, ysln, lib="scipy")

# Visualize the solution
view = ScalarView("Von Mises stress [Pa]", 50, 50, 1200, 600)
E = float(200e9)
nu = 0.3
l = (E * nu) / ((1 + nu) * (1 - 2 * nu))
mu = E / (2 * (1 + nu))
stress = VonMisesFilter(xsln, ysln, mu, l)
view.show(stress)

# Visualize the mesh
mesh.plot(space=xdisp)
Beispiel #25
0
def test_example_10():
    from hermes2d.examples.c10 import set_bc, set_forms
    from hermes2d.examples import get_motor_mesh

    # The following parameters can be changed:
    SOLVE_ON_COARSE_MESH = True  # If true, coarse mesh FE problem is solved in every adaptivity step
    P_INIT = 2  # Initial polynomial degree of all mesh elements.
    THRESHOLD = 0.2  # This is a quantitative parameter of the adapt(...) function and
    # it has different meanings for various adaptive strategies (see below).

    STRATEGY = 1  # Adaptive strategy:
    # STRATEGY = 0 ... refine elements until sqrt(THRESHOLD) times total
    #   error is processed. If more elements have similar errors, refine
    #   all to keep the mesh symmetric.
    # STRATEGY = 1 ... refine all elements whose error is larger
    #   than THRESHOLD times maximum element error.
    # STRATEGY = 2 ... refine all elements whose error is larger
    #   than THRESHOLD.
    # More adaptive strategies can be created in adapt_ortho_h1.cpp.

    CAND_LIST = CandList.H2D_HP_ANISO_H  # Predefined list of element refinement candidates.
    # Possible values are are attributes of the class CandList:
    # H2D_P_ISO, H2D_P_ANISO, H2D_H_ISO, H2D_H_ANISO, H2D_HP_ISO, H2D_HP_ANISO_H, H2D_HP_ANISO_P, H2D_HP_ANISO
    # See User Documentation for details.

    MESH_REGULARITY = -1  # Maximum allowed level of hanging nodes:
    # MESH_REGULARITY = -1 ... arbitrary level hangning nodes (default),
    # MESH_REGULARITY = 1 ... at most one-level hanging nodes,
    # MESH_REGULARITY = 2 ... at most two-level hanging nodes, etc.
    # Note that regular meshes are not supported, this is due to
    # their notoriously bad performance.

    ERR_STOP = 1.0  # Stopping criterion for adaptivity (rel. error tolerance between the
    # fine mesh and coarse mesh solution in percent).
    CONV_EXP = 1.0
    # Default value is 1.0. This parameter influences the selection of
    # cancidates in hp-adaptivity. See get_optimal_refinement() for details.
    # fine mesh and coarse mesh solution in percent).
    NDOF_STOP = 60000  # Adaptivity process stops when the number of degrees of freedom grows
    # over this limit. This is to prevent h-adaptivity to go on forever.

    H2DRS_DEFAULT_ORDER = -1  # A default order. Used to indicate an unkonwn order or a maximum support order

    # Load the mesh
    mesh = Mesh()
    mesh.load(get_motor_mesh())

    # Create an H1 space with default shapeset
    space = H1Space(mesh, P_INIT)
    set_bc(space)

    # Initialize the discrete problem
    wf = WeakForm()
    set_forms(wf)

    # Initialize refinement selector.
    selector = H1ProjBasedSelector(CAND_LIST, CONV_EXP, H2DRS_DEFAULT_ORDER)

    # Initialize the linear system.
    ls = LinSystem(wf)
    ls.set_spaces(space)

    sln_coarse = Solution()
    sln_fine = Solution()

    # Assemble and solve the fine mesh problem
    rs = RefSystem(ls)
    rs.assemble()
    rs.solve_system(sln_fine)

    # Either solve on coarse mesh or project the fine mesh solution
    # on the coarse mesh.
    if SOLVE_ON_COARSE_MESH:
        ls.assemble()
        ls.solve_system(sln_coarse)

    # Calculate element errors and total error estimate
    hp = H1Adapt(ls)
    hp.set_solutions([sln_coarse], [sln_fine])
    err_est = hp.calc_error() * 100
Beispiel #26
0
sview = ScalarView("Solution")
mview = MeshView("Mesh")
graph = []

# Initialize refinement selector
selector = H1ProjBasedSelector(CAND_LIST, CONV_EXP, H2DRS_DEFAULT_ORDER)

# Initialize the coarse mesh problem
ls = LinSystem(wf)
ls.set_spaces(space)

# Adaptivity loop
iter = 0
done =  False
print "Calculating..."
sln_coarse = Solution()
sln_fine = Solution()

while (not done):
    
    # Assemble and solve the fine mesh problem
    rs = RefSystem(ls)
    rs.assemble()
    rs.solve_system(sln_fine)
    
    # Either solve on coarse mesh or project the fine mesh solution 
    # on the coarse mesh.   
    if SOLVE_ON_COARSE_MESH:
        ls.assemble()
        ls.solve_system(sln_coarse)
    else:
Beispiel #27
0
mesh.refine_towards_boundary(2, 5)

# Set up shapeset
shapeset = H1Shapeset()
pss = PrecalcShapeset(shapeset)

# Set up spaces
space = H1Space(mesh, shapeset)
set_bc(space)
space.set_uniform_order(P_INIT)

# Enumerate basis functions
space.assign_dofs()

# Set initial condition
tsln = Solution()
tsln.set_const(mesh, T_INIT)

# Weak formulation
wf = WeakForm(1)
set_forms(wf, tsln)

# Matrix solver
solver = DummySolver()

# Linear system
ls = LinSystem(wf, solver)
ls.set_spaces(space)
ls.set_pss(pss)

# Visualisation