Exemple #1
0
    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")
Exemple #2
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# 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:
        ls.project_global(sln_fine, sln_coarse)
    
    # View the solution and mesh
    sview.show(sln_coarse);
    mesh.plot(space=space)
        
Exemple #3
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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
Exemple #4
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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
Exemple #5
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