Beispiel #1
0
    def create_mesh(self, extra_nodes=True):
        """
        Create a mesh from the field region, optionally including the field
        extra nodes.
        """
        mesh = self.domain.mesh

        if self.approx_order != 0:
            conns, mat_ids, descs = [], [], []
            for ig, ap in self.aps.iteritems():
                group = self.domain.groups[ig]
                if extra_nodes:
                    conn = ap.econn
                else:
                    offset = group.shape.n_ep
                    conn = ap.econn[:,:offset]
                conns.append(conn)
                mat_ids.append(mesh.mat_ids[ig])
                descs.append(mesh.descs[ig])

            if extra_nodes:
                coors = self.coors

            else:
                coors = self.coors[:self.n_vertex_dof]

            mesh = Mesh.from_data(self.name, coors, None, conns,
                                  mat_ids, descs)

        return mesh
Beispiel #2
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def gen_block_mesh(dims, shape, centre, mat_id=0, name='block',
                   coors=None, verbose=True):
    """
    Generate a 2D or 3D block mesh. The dimension is determined by the
    lenght of the shape argument.

    Parameters
    ----------
    dims : array of 2 or 3 floats
        Dimensions of the block.
    shape : array of 2 or 3 ints
        Shape (counts of nodes in x, y, z) of the block mesh.
    centre : array of 2 or 3 floats
        Centre of the block.
    mat_id : int, optional
        The material id of all elements.
    name : string
        Mesh name.
    verbose : bool
        If True, show progress of the mesh generation.

    Returns
    -------
    mesh : Mesh instance
    """
    dims = nm.asarray(dims, dtype=nm.float64)
    shape = nm.asarray(shape, dtype=nm.int32)
    centre = nm.asarray(centre, dtype=nm.float64)

    dim = shape.shape[0]

    centre = centre[:dim]
    dims = dims[:dim]

    n_nod = nm.prod(shape)
    output('generating %d vertices...' % n_nod, verbose=verbose)

    x0 = centre - 0.5 * dims
    dd = dims / (shape - 1)

    ngrid = nm.mgrid[[slice(ii) for ii in shape]]
    ngrid.shape = (dim, n_nod)

    coors = x0 + ngrid.T * dd
    output('...done', verbose=verbose)

    n_el = nm.prod(shape - 1)
    output('generating %d cells...' % n_el, verbose=verbose)

    mat_ids = nm.empty((n_el,), dtype=nm.int32)
    mat_ids.fill(mat_id)

    conn, desc = get_tensor_product_conn(shape)
    output('...done', verbose=verbose)

    mesh = Mesh.from_data(name, coors, None, [conn], [mat_ids], [desc])
    return mesh
Beispiel #3
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    def create_mesh_from_control_points( self ):
        offset = 0
        dim = self.spbs[0].cxyz.shape[1]
        coors = nm.empty((0, dim), dtype=nm.float64)
        conns = []
        mat_ids = []
        descs = []
        for ib, spb in enumerate( self.spbs ):
            n_nod = spb.cxyz.shape[0]
            coors = nm.concatenate( (coors, spb.cxyz), 0 )
            descs.append( '3_2' )

            conn = []
            for ij in xrange( spb.cpi.shape[1] ):
                for ik in xrange( spb.cpi.shape[2] ):
                    inx = spb.cpi[:,ij,ik]
                    row = [[p1, p2] for p1, p2 in zip( inx[:-1], inx[1:] )]
                    conn.extend( row )
            for ij in xrange( spb.cpi.shape[0] ):
                for ik in xrange( spb.cpi.shape[2] ):
                    inx = spb.cpi[ij,:,ik]
                    row = [[p1, p2] for p1, p2 in zip( inx[:-1], inx[1:] )]
                    conn.extend( row )
            for ij in xrange( spb.cpi.shape[0] ):
                for ik in xrange( spb.cpi.shape[1] ):
                    inx = spb.cpi[ij,ik,:]
                    row = [[p1, p2] for p1, p2 in zip( inx[:-1], inx[1:] )]
                    conn.extend( row )

            aux = nm.empty(len(conn), dtype=nm.int32)
            aux.fill(ib)
            mat_ids.append(aux)

            conns.append( offset + nm.array( conn, dtype = nm.int32 ) )
            offset += n_nod

        mesh = Mesh.from_data('control_points', coors, None, conns,
                              mat_ids, descs)
        return mesh
Beispiel #4
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    def create_mesh_from_control_points( self ):
        offset = 0
        dim = self.spbs[0].cxyz.shape[1]
        coors = nm.empty((0, dim), dtype=nm.float64)
        conns = []
        mat_ids = []
        descs = []
        for ib, spb in enumerate( self.spbs ):
            n_nod = spb.cxyz.shape[0]
            coors = nm.concatenate( (coors, spb.cxyz), 0 )
            descs.append( '3_2' )

            conn = []
            for ij in xrange( spb.cpi.shape[1] ):
                for ik in xrange( spb.cpi.shape[2] ):
                    inx = spb.cpi[:,ij,ik]
                    row = [[p1, p2] for p1, p2 in zip( inx[:-1], inx[1:] )]
                    conn.extend( row )
            for ij in xrange( spb.cpi.shape[0] ):
                for ik in xrange( spb.cpi.shape[2] ):
                    inx = spb.cpi[ij,:,ik]
                    row = [[p1, p2] for p1, p2 in zip( inx[:-1], inx[1:] )]
                    conn.extend( row )
            for ij in xrange( spb.cpi.shape[0] ):
                for ik in xrange( spb.cpi.shape[1] ):
                    inx = spb.cpi[ij,ik,:]
                    row = [[p1, p2] for p1, p2 in zip( inx[:-1], inx[1:] )]
                    conn.extend( row )

            aux = nm.empty(len(conn), dtype=nm.int32)
            aux.fill(ib)
            mat_ids.append(aux)

            conns.append( offset + nm.array( conn, dtype = nm.int32 ) )
            offset += n_nod

        mesh = Mesh.from_data('control_points', coors, None, conns,
                              mat_ids, descs)
        return mesh
Beispiel #5
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def gen_cylinder_mesh(dims,
                      shape,
                      centre,
                      axis='x',
                      force_hollow=False,
                      is_open=False,
                      open_angle=0.0,
                      non_uniform=False,
                      name='cylinder',
                      verbose=True):
    """
    Generate a cylindrical mesh along an axis. Its cross-section can be
    ellipsoidal.

    Parameters
    ----------
    dims : array of 5 floats
        Dimensions of the cylinder: inner surface semi-axes a1, b1, outer
        surface semi-axes a2, b2, length.
    shape : array of 3 ints
        Shape (counts of nodes in radial, circumferential and longitudinal
        directions) of the cylinder mesh.
    centre : array of 3 floats
        Centre of the cylinder.
    axis: one of 'x', 'y', 'z'
        The axis of the cylinder.
    force_hollow : boolean
        Force hollow mesh even if inner radii a1 = b1 = 0.
    is_open : boolean
        Generate an open cylinder segment.
    open_angle : float
        Opening angle in radians.
    non_uniform : boolean
        If True, space the mesh nodes in radial direction so that the element
        volumes are (approximately) the same, making thus the elements towards
        the outer surface thinner.
    name : string
        Mesh name.
    verbose : bool
        If True, show progress of the mesh generation.

    Returns
    -------
    mesh : Mesh instance
    """
    dims = nm.asarray(dims, dtype=nm.float64)
    shape = nm.asarray(shape, dtype=nm.int32)
    centre = nm.asarray(centre, dtype=nm.float64)

    a1, b1, a2, b2, length = dims
    nr, nfi, nl = shape
    origin = centre - nm.array([0.5 * length, 0.0, 0.0])

    dfi = 2.0 * (nm.pi - open_angle) / nfi
    if is_open:
        nnfi = nfi + 1
    else:
        nnfi = nfi

    is_hollow = force_hollow or not (max(abs(a1), abs(b1)) < 1e-15)

    if is_hollow:
        mr = 0
    else:
        mr = (nnfi - 1) * nl

    grid = nm.zeros((nr, nnfi, nl), dtype=nm.int32)

    n_nod = nr * nnfi * nl - mr
    coors = nm.zeros((n_nod, 3), dtype=nm.float64)

    angles = nm.linspace(open_angle, open_angle + (nfi) * dfi, nfi + 1)
    xs = nm.linspace(0.0, length, nl)
    if non_uniform:
        ras = nm.zeros((nr, ), dtype=nm.float64)
        rbs = nm.zeros_like(ras)
        advol = (a2**2 - a1**2) / (nr - 1)
        bdvol = (b2**2 - b1**2) / (nr - 1)
        ras[0], rbs[0] = a1, b1
        for ii in range(1, nr):
            ras[ii] = nm.sqrt(advol + ras[ii - 1]**2)
            rbs[ii] = nm.sqrt(bdvol + rbs[ii - 1]**2)
    else:
        ras = nm.linspace(a1, a2, nr)
        rbs = nm.linspace(b1, b2, nr)

    # This is 3D only...
    bar = MyBar("       nodes:", verbose=verbose)
    bar.init(n_nod)
    ii = 0
    for ix in range(nr):
        a, b = ras[ix], rbs[ix]
        for iy, fi in enumerate(angles[:nnfi]):
            for iz, x in enumerate(xs):
                grid[ix, iy, iz] = ii
                coors[ii] = origin + [x, a * nm.cos(fi), b * nm.sin(fi)]
                if not (ii % 100):
                    bar.update(ii)
                ii += 1

                if not is_hollow and (ix == 0):
                    if iy > 0:
                        grid[ix, iy, iz] = grid[ix, 0, iz]
                        ii -= 1
    assert_(ii == n_nod)

    n_el = (nr - 1) * nnfi * (nl - 1)
    conn = nm.zeros((n_el, 8), dtype=nm.int32)

    bar = MyBar("       elements:", verbose=verbose)
    bar.init(n_el)
    ii = 0
    for (ix, iy, iz) in cycle([nr - 1, nnfi, nl - 1]):
        if iy < (nnfi - 1):
            conn[ii, :] = [
                grid[ix, iy, iz], grid[ix + 1, iy, iz], grid[ix + 1, iy + 1,
                                                             iz],
                grid[ix, iy + 1, iz], grid[ix, iy, iz + 1], grid[ix + 1, iy,
                                                                 iz + 1],
                grid[ix + 1, iy + 1, iz + 1], grid[ix, iy + 1, iz + 1]
            ]
            ii += 1
        elif not is_open:
            conn[ii, :] = [
                grid[ix, iy, iz], grid[ix + 1, iy, iz], grid[ix + 1, 0, iz],
                grid[ix, 0, iz], grid[ix, iy, iz + 1],
                grid[ix + 1, iy, iz + 1], grid[ix + 1, 0, iz + 1], grid[ix, 0,
                                                                        iz + 1]
            ]
            ii += 1

        if not (ii % 100):
            bar.update(ii)

    mat_id = nm.zeros((n_el, ), dtype=nm.int32)
    desc = '3_8'

    assert_(n_nod == (conn.max() + 1))

    if axis == 'z':
        coors = coors[:, [1, 2, 0]]
    elif axis == 'y':
        coors = coors[:, [2, 0, 1]]

    mesh = Mesh.from_data(name, coors, None, [conn], [mat_id], [desc])
    return mesh
Beispiel #6
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def gen_mesh_from_voxels(voxels, dims, etype='q'):
    """
    Generate FE mesh from voxels (volumetric data).

    Parameters
    ----------
    voxels : array
        Voxel matrix, 1=material.
    dims : array
        Size of one voxel.
    etype : integer, optional
        'q' - quadrilateral or hexahedral elements
        't' - triangular or tetrahedral elements
    Returns
    -------
    mesh : Mesh instance
        Finite element mesh.
    """

    dims = dims.squeeze()
    dim = len(dims)
    nddims = nm.array(voxels.shape) + 2

    nodemtx = nm.zeros(nddims, dtype=nm.int32)

    if dim == 2:
        #iy, ix = nm.where(voxels.transpose())
        iy, ix = nm.where(voxels)
        nel = ix.shape[0]

        if etype == 'q':
            nodemtx[ix, iy] += 1
            nodemtx[ix + 1, iy] += 1
            nodemtx[ix + 1, iy + 1] += 1
            nodemtx[ix, iy + 1] += 1

        elif etype == 't':
            nodemtx[ix, iy] += 2
            nodemtx[ix + 1, iy] += 1
            nodemtx[ix + 1, iy + 1] += 2
            nodemtx[ix, iy + 1] += 1
            nel *= 2

    elif dim == 3:
        #iy, ix, iz = nm.where(voxels.transpose(1, 0, 2))
        iy, ix, iz = nm.where(voxels)
        nel = ix.shape[0]

        if etype == 'q':
            nodemtx[ix, iy, iz] += 1
            nodemtx[ix + 1, iy, iz] += 1
            nodemtx[ix + 1, iy + 1, iz] += 1
            nodemtx[ix, iy + 1, iz] += 1
            nodemtx[ix, iy, iz + 1] += 1
            nodemtx[ix + 1, iy, iz + 1] += 1
            nodemtx[ix + 1, iy + 1, iz + 1] += 1
            nodemtx[ix, iy + 1, iz + 1] += 1

        elif etype == 't':
            nodemtx[ix, iy, iz] += 6
            nodemtx[ix + 1, iy, iz] += 2
            nodemtx[ix + 1, iy + 1, iz] += 2
            nodemtx[ix, iy + 1, iz] += 2
            nodemtx[ix, iy, iz + 1] += 2
            nodemtx[ix + 1, iy, iz + 1] += 2
            nodemtx[ix + 1, iy + 1, iz + 1] += 6
            nodemtx[ix, iy + 1, iz + 1] += 2
            nel *= 6

    else:
        msg = 'incorrect voxel dimension! (%d)' % dim
        raise ValueError(msg)

    ndidx = nm.where(nodemtx)
    coors = nm.array(ndidx).transpose() * dims
    nnod = coors.shape[0]

    nodeid = -nm.ones(nddims, dtype=nm.int32)
    nodeid[ndidx] = nm.arange(nnod)

    # generate elements
    if dim == 2:
        elems = nm.array([
            nodeid[ix, iy], nodeid[ix + 1, iy], nodeid[ix + 1, iy + 1],
            nodeid[ix, iy + 1]
        ]).transpose()

    elif dim == 3:
        elems = nm.array([
            nodeid[ix, iy, iz], nodeid[ix + 1, iy, iz], nodeid[ix + 1, iy + 1,
                                                               iz],
            nodeid[ix, iy + 1, iz], nodeid[ix, iy, iz + 1], nodeid[ix + 1, iy,
                                                                   iz + 1],
            nodeid[ix + 1, iy + 1, iz + 1], nodeid[ix, iy + 1, iz + 1]
        ]).transpose()

    if etype == 't':
        elems = elems_q2t(elems)

    eid = etype + str(dim)
    eltab = {'q2': 4, 'q3': 8, 't2': 3, 't3': 4}

    mesh = Mesh.from_data('voxel_data', coors, nm.ones(
        (nnod, ), dtype=nm.int32), {0: nm.ascontiguousarray(elems)},
                          {0: nm.ones((nel, ), dtype=nm.int32)},
                          {0: '%d_%d' % (dim, eltab[eid])})

    return mesh
Beispiel #7
0
def gen_tiled_mesh(mesh, grid=None, scale=1.0, eps=1e-6, ret_ndmap=False):
    """
    Generate a new mesh by repeating a given periodic element
    along each axis.

    Parameters
    ----------
    mesh : Mesh instance
        The input periodic FE mesh.
    grid : array
        Number of repetition along each axis.
    scale : float, optional
        Scaling factor.
    eps : float, optional
        Tolerance for boundary detection.
    ret_ndmap : bool, optional
        If True, return global node map.

    Returns
    -------
    mesh_out : Mesh instance
        FE mesh.
    ndmap : array
        Maps: actual node id --> node id in the reference cell.
    """
    bbox = mesh.get_bounding_box()

    if grid is None:
        iscale = max(int(1.0 / scale), 1)
        grid = [iscale] * mesh.dim

    conns = mesh.conns[0]
    for ii in mesh.conns[1:]:
        conns = nm.vstack((conns, ii))
    mat_ids = mesh.mat_ids[0]
    for ii in mesh.mat_ids[1:]:
        mat_ids = nm.hstack((mat_ids, ii))

    coors = mesh.coors
    ngrps = mesh.ngroups
    nrep = nm.prod(grid)
    ndmap = None

    bar = MyBar("       repeating:")
    bar.init(nrep)
    nblk = 1
    for ii, gr in enumerate(grid):
        if ret_ndmap:
            (conns, coors, ngrps, ndmap0) = tiled_mesh1d(conns,
                                                         coors,
                                                         ngrps,
                                                         ii,
                                                         gr,
                                                         bbox.transpose()[ii],
                                                         eps=eps,
                                                         mybar=(bar, nblk),
                                                         ndmap=ndmap)
            ndmap = ndmap0

        else:
            conns, coors, ngrps = tiled_mesh1d(conns,
                                               coors,
                                               ngrps,
                                               ii,
                                               gr,
                                               bbox.transpose()[ii],
                                               eps=eps,
                                               mybar=(bar, nblk))
        nblk *= gr

    bar.update(nblk)

    mat_ids = nm.tile(mat_ids, (nrep, ))
    mesh_out = Mesh.from_data('tiled mesh', coors * scale, ngrps, [conns],
                              [mat_ids], [mesh.descs[0]])

    if ret_ndmap:
        return mesh_out, ndmap
    else:
        return mesh_out
Beispiel #8
0
def gen_block_mesh(dims, shape, centre, mat_id=0, name='block', verbose=True):
    """
    Generate a 2D or 3D block mesh. The dimension is determined by the
    lenght of the shape argument.

    Parameters
    ----------
    dims : array of 2 or 3 floats
        Dimensions of the block.
    shape : array of 2 or 3 ints
        Shape (counts of nodes in x, y, z) of the block mesh.
    centre : array of 2 or 3 floats
        Centre of the block.
    mat_id : int, optional
        The material id of all elements.
    name : string
        Mesh name.
    verbose : bool
        If True, show progress of the mesh generation.

    Returns
    -------
    mesh : Mesh instance
    """
    dims = nm.asarray(dims, dtype=nm.float64)
    shape = nm.asarray(shape, dtype=nm.int32)
    centre = nm.asarray(centre, dtype=nm.float64)

    dim = shape.shape[0]

    centre = centre[:dim]
    dims = dims[:dim]

    x0 = centre - 0.5 * dims
    dd = dims / (shape - 1)

    grid = nm.zeros(shape, dtype=nm.int32)
    n_nod = nm.prod(shape)
    coors = nm.zeros((n_nod, dim), dtype=nm.float64)

    bar = MyBar("       nodes:", verbose=verbose)
    bar.init(n_nod)
    for ii, ic in enumerate(cycle(shape)):
        grid[tuple(ic)] = ii
        coors[ii] = x0 + ic * dd
        if not (ii % 100):
            bar.update(ii)
    bar.update(ii + 1)

    n_el = nm.prod(shape - 1)
    mat_ids = nm.empty((n_el, ), dtype=nm.int32)
    mat_ids.fill(mat_id)

    if (dim == 2):
        conn = nm.zeros((n_el, 4), dtype=nm.int32)
        bar = MyBar("       elements:", verbose=verbose)
        bar.init(n_el)
        for ii, (ix, iy) in enumerate(cycle(shape - 1)):
            conn[ii, :] = [
                grid[ix, iy], grid[ix + 1, iy], grid[ix + 1, iy + 1],
                grid[ix, iy + 1]
            ]
            if not (ii % 100):
                bar.update(ii)
        bar.update(ii + 1)
        desc = '2_4'

    else:
        conn = nm.zeros((n_el, 8), dtype=nm.int32)
        bar = MyBar("       elements:", verbose=verbose)
        bar.init(n_el)
        for ii, (ix, iy, iz) in enumerate(cycle(shape - 1)):
            conn[ii, :] = [
                grid[ix, iy, iz], grid[ix + 1, iy, iz], grid[ix + 1, iy + 1,
                                                             iz],
                grid[ix, iy + 1, iz], grid[ix, iy, iz + 1], grid[ix + 1, iy,
                                                                 iz + 1],
                grid[ix + 1, iy + 1, iz + 1], grid[ix, iy + 1, iz + 1]
            ]
            if not (ii % 100):
                bar.update(ii)
        bar.update(ii + 1)
        desc = '3_8'

    mesh = Mesh.from_data(name, coors, None, [conn], [mat_ids], [desc])
    return mesh
Beispiel #9
0
def gen_block_mesh(dims, shape, centre, name='block'):
    """
    Generate a 2D or 3D block mesh. The dimension is determined by the
    lenght of the shape argument.

    Parameters
    ----------
    dims : array of 2 or 3 floats
        Dimensions of the block.
    shape : array of 2 or 3 ints
        Shape (counts of nodes in x, y, z) of the block mesh.
    centre : array of 2 or 3 floats
        Centre of the block.

    name : string
        Mesh name.

    Returns
    -------
    mesh : Mesh instance
    """
    dims = nm.asarray(dims, dtype=nm.float64)
    shape = nm.asarray(shape, dtype=nm.int32)
    centre = nm.asarray(centre, dtype=nm.float64)

    dim = shape.shape[0]

    centre = centre[:dim]
    dims = dims[:dim]

    x0 = centre - 0.5 * dims
    dd = dims / (shape - 1)

    grid = nm.zeros(shape, dtype = nm.int32)
    n_nod = nm.prod(shape)
    coors = nm.zeros((n_nod, dim), dtype = nm.float64)

    bar = MyBar("       nodes:")
    bar.init(n_nod)
    for ii, ic in enumerate(cycle(shape)):
        grid[tuple(ic)] = ii
        coors[ii] = x0 + ic * dd
        if not (ii % 100):
            bar.update(ii)
    bar.update(ii + 1)

    n_el = nm.prod(shape - 1)
    mat_id = nm.zeros((n_el,), dtype = nm.int32)

    if (dim == 2):
        conn = nm.zeros((n_el, 4), dtype = nm.int32)
        bar = MyBar("       elements:")
        bar.init(n_el)
        for ii, (ix, iy) in enumerate(cycle(shape - 1)):
            conn[ii,:] = [grid[ix  ,iy], grid[ix+1,iy  ],
                          grid[ix+1,iy+1], grid[ix  ,iy+1]]
            if not (ii % 100):
                bar.update(ii)
        bar.update(ii + 1)
        desc = '2_4'

    else:
        conn = nm.zeros((n_el, 8), dtype = nm.int32)
        bar = MyBar("       elements:")
        bar.init(n_el)
        for ii, (ix, iy, iz) in enumerate(cycle(shape - 1)):
            conn[ii,:] = [grid[ix  ,iy  ,iz  ], grid[ix+1,iy  ,iz  ],
                          grid[ix+1,iy+1,iz  ], grid[ix  ,iy+1,iz  ],
                          grid[ix  ,iy  ,iz+1], grid[ix+1,iy  ,iz+1],
                          grid[ix+1,iy+1,iz+1], grid[ix  ,iy+1,iz+1]]
            if not (ii % 100):
                bar.update(ii)
        bar.update(ii + 1)
        desc = '3_8'

    mesh = Mesh.from_data(name, coors, None, [conn], [mat_id], [desc])
    return mesh
Beispiel #10
0
def gen_cylinder_mesh(dims, shape, centre, axis='x', force_hollow=False,
                      is_open=False, open_angle=0.0, non_uniform=False,
                      name='cylinder'):
    """
    Generate a cylindrical mesh along an axis. Its cross-section can be
    ellipsoidal.

    Parameters
    ----------
    axis: one of 'x', 'y', 'z'
        The axis of the cylinder.
    dims : array of 5 floats
        Dimensions of the cylinder: inner surface semi-axes a1, b1, outer
        surface semi-axes a2, b2, length.
    shape : array of 3 ints
        Shape (counts of nodes in radial, circumferential and longitudinal
        directions) of the cylinder mesh.
    centre : array of 3 floats
        Centre of the cylinder.

    force_hollow : boolean
        Force hollow mesh even if inner radii a1 = b1 = 0.

    is_open : boolean
        Generate an open cylinder segment.
    open_angle : float
        Opening angle in radians.

    non_uniform : boolean
        If True, space the mesh nodes in radial direction so that the element
        volumes are (approximately) the same, making thus the elements towards
        the outer surface thinner.

    name : string
        Mesh name.

    Returns
    -------
    mesh : Mesh instance
    """
    dims = nm.asarray(dims, dtype=nm.float64)
    shape = nm.asarray(shape, dtype=nm.int32)
    centre = nm.asarray(centre, dtype=nm.float64)

    a1, b1, a2, b2, length = dims
    nr, nfi, nl = shape
    origin = centre - nm.array([0.5 * length, 0.0, 0.0])

    dfi = 2.0 * (nm.pi - open_angle) / nfi
    if is_open:
        nnfi = nfi + 1
    else:
        nnfi = nfi

    is_hollow = force_hollow or not (max(abs(a1), abs(b1)) < 1e-15)

    if is_hollow:
        mr = 0
    else:
        mr = (nnfi - 1) * nl

    grid = nm.zeros((nr, nnfi, nl), dtype=nm.int32)

    n_nod = nr * nnfi * nl - mr
    coors = nm.zeros((n_nod, 3), dtype=nm.float64)

    angles = nm.linspace(open_angle, open_angle+(nfi)*dfi, nfi+1)
    xs = nm.linspace(0.0, length, nl)
    if non_uniform:
        ras = nm.zeros((nr,), dtype=nm.float64)
        rbs = nm.zeros_like(ras)
        advol = (a2**2 - a1**2) / (nr - 1)
        bdvol = (b2**2 - b1**2) / (nr - 1)
        ras[0], rbs[0] = a1, b1
        for ii in range(1, nr):
            ras[ii] = nm.sqrt(advol + ras[ii-1]**2)
            rbs[ii] = nm.sqrt(bdvol + rbs[ii-1]**2)
    else:
        ras = nm.linspace(a1, a2, nr)
        rbs = nm.linspace(b1, b2, nr)

    # This is 3D only...
    bar = MyBar("       nodes:")
    bar.init(n_nod)
    ii = 0
    for ix in range(nr):
        a, b = ras[ix], rbs[ix]
        for iy, fi in enumerate(angles[:nnfi]):
            for iz, x in enumerate(xs):
                grid[ix,iy,iz] = ii
                coors[ii] = origin + [x, a * nm.cos(fi), b * nm.sin(fi)]
                if not (ii % 100):
                    bar.update(ii)
                ii += 1

                if not is_hollow and (ix == 0):
                    if iy > 0:
                        grid[ix,iy,iz] = grid[ix,0,iz]
                        ii -= 1
    print
    assert_(ii == n_nod)

    n_el = (nr - 1) * nnfi * (nl - 1)
    conn = nm.zeros((n_el, 8), dtype=nm.int32)

    bar = MyBar("       elements:")
    bar.init(n_el)
    ii = 0
    for (ix, iy, iz) in cycle([nr-1, nnfi, nl-1]):
        if iy < (nnfi - 1):
            conn[ii,:] = [grid[ix  ,iy  ,iz  ], grid[ix+1,iy  ,iz  ],
                          grid[ix+1,iy+1,iz  ], grid[ix  ,iy+1,iz  ],
                          grid[ix  ,iy  ,iz+1], grid[ix+1,iy  ,iz+1],
                          grid[ix+1,iy+1,iz+1], grid[ix  ,iy+1,iz+1]]
            ii += 1
        elif not is_open:
            conn[ii,:] = [grid[ix  ,iy  ,iz  ], grid[ix+1,iy  ,iz  ],
                          grid[ix+1,0,iz  ], grid[ix  ,0,iz  ],
                          grid[ix  ,iy  ,iz+1], grid[ix+1,iy  ,iz+1],
                          grid[ix+1,0,iz+1], grid[ix  ,0,iz+1]]
            ii += 1

        if not (ii % 100):
            bar.update(ii)
    print
    mat_id = nm.zeros((n_el,), dtype = nm.int32)
    desc = '3_8'

    assert_(n_nod == (conn.max() + 1))

    if axis == 'z':
        coors = coors[:,[1,2,0]]
    elif axis == 'y':
        coors = coors[:,[2,0,1]]

    mesh = Mesh.from_data(name, coors, None, [conn], [mat_id], [desc])
    return mesh
Beispiel #11
0
def gen_mesh_from_voxels(voxels, dims, etype='q'):
    """
    Generate FE mesh from voxels (volumetric data).

    Parameters
    ----------
    voxels : array
        Voxel matrix, 1=material.
    dims : array
        Size of one voxel.
    etype : integer, optional
        'q' - quadrilateral or hexahedral elements
        't' - triangular or tetrahedral elements
    Returns
    -------
    mesh : Mesh instance
        Finite element mesh.
    """

    dims = dims.squeeze()
    dim = len(dims)
    nddims = nm.array(voxels.shape) + 1

    nodemtx = nm.zeros(nddims, dtype=nm.int32)

    if dim == 2:
        #iy, ix = nm.where(voxels.transpose())
        iy, ix = nm.where(voxels)
        nel = ix.shape[0]

        if etype == 'q':
            nodemtx[ix,iy] += 1
            nodemtx[ix + 1,iy] += 1
            nodemtx[ix + 1,iy + 1] += 1
            nodemtx[ix,iy + 1] += 1

        elif etype == 't':
            nodemtx[ix,iy] += 2
            nodemtx[ix + 1,iy] += 1
            nodemtx[ix + 1,iy + 1] += 2
            nodemtx[ix,iy + 1] += 1
            nel *= 2

    elif dim == 3:
        #iy, ix, iz = nm.where(voxels.transpose(1, 0, 2))
        iy, ix, iz = nm.where(voxels)
        nel = ix.shape[0]

        if etype == 'q':
            nodemtx[ix,iy,iz] += 1
            nodemtx[ix + 1,iy,iz] += 1
            nodemtx[ix + 1,iy + 1,iz] += 1
            nodemtx[ix,iy + 1,iz] += 1
            nodemtx[ix,iy,iz + 1] += 1
            nodemtx[ix + 1,iy,iz + 1] += 1
            nodemtx[ix + 1,iy + 1,iz + 1] += 1
            nodemtx[ix,iy + 1,iz + 1] += 1

        elif etype == 't':
            nodemtx[ix,iy,iz] += 6
            nodemtx[ix + 1,iy,iz] += 2
            nodemtx[ix + 1,iy + 1,iz] += 2
            nodemtx[ix,iy + 1,iz] += 2
            nodemtx[ix,iy,iz + 1] += 2
            nodemtx[ix + 1,iy,iz + 1] += 2
            nodemtx[ix + 1,iy + 1,iz + 1] += 6
            nodemtx[ix,iy + 1,iz + 1] += 2
            nel *= 6

    else:
        msg = 'incorrect voxel dimension! (%d)' % dim
        raise ValueError(msg)

    ndidx = nm.where(nodemtx)
    coors = nm.array(ndidx).transpose() * dims
    nnod = coors.shape[0]

    nodeid = -nm.ones(nddims, dtype=nm.int32)
    nodeid[ndidx] = nm.arange(nnod)

    # generate elements
    if dim == 2:
        elems = nm.array([nodeid[ix,iy],
                          nodeid[ix + 1,iy],
                          nodeid[ix + 1,iy + 1],
                          nodeid[ix,iy + 1]]).transpose()

    elif dim == 3:
        elems = nm.array([nodeid[ix,iy,iz],
                          nodeid[ix + 1,iy,iz],
                          nodeid[ix + 1,iy + 1,iz],
                          nodeid[ix,iy + 1,iz],
                          nodeid[ix,iy,iz + 1],
                          nodeid[ix + 1,iy,iz + 1],
                          nodeid[ix + 1,iy + 1,iz + 1],
                          nodeid[ix,iy + 1,iz + 1]]).transpose()

    if etype == 't':
        elems = elems_q2t(elems)

    eid = etype + str(dim)
    eltab = {'q2': 4, 'q3': 8, 't2': 3, 't3': 4}

    mesh = Mesh.from_data('voxel_data',
                          coors, nm.ones((nnod,), dtype=nm.int32),
                          {0: nm.ascontiguousarray(elems)},
                          {0: nm.ones((nel,), dtype=nm.int32)},
                          {0: '%d_%d' % (dim, eltab[eid])})

    return mesh
Beispiel #12
0
def gen_tiled_mesh(mesh, grid=None, scale=1.0, eps=1e-6, ret_ndmap=False):
    """
    Generate a new mesh by repeating a given periodic element
    along each axis.

    Parameters
    ----------
    mesh : Mesh instance
        The input periodic FE mesh.
    grid : array
        Number of repetition along each axis.
    scale : float, optional
        Scaling factor.
    eps : float, optional
        Tolerance for boundary detection.
    ret_ndmap : bool, optional
        If True, return global node map.

    Returns
    -------
    mesh_out : Mesh instance
        FE mesh.
    ndmap : array
        Maps: actual node id --> node id in the reference cell.
    """
    bbox = mesh.get_bounding_box()

    if grid is None:
        iscale = max(int(1.0 / scale), 1)
        grid = [iscale] * mesh.dim

    conns = mesh.conns[0]
    for ii in mesh.conns[1:]:
        conns = nm.vstack((conns, ii))
    mat_ids = mesh.mat_ids[0]
    for ii in mesh.mat_ids[1:]:
        mat_ids = nm.hstack((mat_ids, ii))

    coors = mesh.coors
    ngrps = mesh.ngroups
    nrep = nm.prod(grid)
    ndmap = None

    bar = MyBar("       repeating:")
    bar.init(nrep)
    nblk = 1
    for ii, gr in enumerate(grid):
        if ret_ndmap:
            (conns, coors,
             ngrps, ndmap0) = tiled_mesh1d(conns, coors, ngrps,
                                           ii, gr, bbox.transpose()[ii],
                                           eps=eps, mybar=(bar, nblk),
                                           ndmap=ndmap)
            ndmap = ndmap0

        else:
            conns, coors, ngrps = tiled_mesh1d(conns, coors, ngrps,
                                               ii, gr, bbox.transpose()[ii],
                                               eps=eps, mybar=(bar, nblk))
        nblk *= gr

    bar.update(nblk)

    mat_ids = nm.tile(mat_ids, (nrep,))
    mesh_out = Mesh.from_data('tiled mesh', coors * scale, ngrps,
                              [conns], [mat_ids], [mesh.descs[0]])

    if ret_ndmap:
        return mesh_out, ndmap
    else:
        return mesh_out
Beispiel #13
0
    def linearize(self, dofs, min_level=0, max_level=1, eps=1e-4):
        """
        Linearize the solution for post-processing.

        Parameters
        ----------
        dofs : array, shape (n_nod, n_component)
            The array of DOFs reshaped so that each column corresponds
            to one component.
        min_level : int
            The minimum required level of mesh refinement.
        max_level : int
            The maximum level of mesh refinement.
        eps : float
            The relative tolerance parameter of mesh adaptivity.

        Returns
        -------
        mesh : Mesh instance
            The adapted, nonconforming, mesh.
        vdofs : array
            The DOFs defined in vertices of `mesh`.
        levels : array of ints
            The refinement level used for each element group.
        """
        assert_(dofs.ndim == 2)

        n_nod, dpn = dofs.shape

        assert_(n_nod == self.n_nod)
        assert_(dpn == self.shape[0])

        vertex_coors = self.coors[:self.n_vertex_dof, :]

        coors = []
        vdofs = []
        conns = []
        mat_ids = []
        levels = []
        offset = 0
        for ig, ap in self.aps.iteritems():
            ps = ap.interp.poly_spaces['v']
            gps = ap.interp.gel.interp.poly_spaces['v']
            group = self.domain.groups[ig]
            vertex_conn = ap.econn[:, :group.shape.n_ep]

            eval_dofs = get_eval_dofs(dofs, ap.econn, ps, ori=ap.ori)
            eval_coors = get_eval_coors(vertex_coors, vertex_conn, gps)

            (level, _coors, conn,
             _vdofs, _mat_ids) = create_output(eval_dofs, eval_coors,
                                               group.shape.n_el, ps,
                                               min_level=min_level,
                                               max_level=max_level, eps=eps)

            _mat_ids[:] = self.domain.mesh.mat_ids[ig][0]

            coors.append(_coors)
            vdofs.append(_vdofs)
            conns.append(conn + offset)
            mat_ids.append(_mat_ids)
            levels.append(level)

            offset += _coors.shape[0]

        coors = nm.concatenate(coors, axis=0)
        vdofs = nm.concatenate(vdofs, axis=0)
        mesh = Mesh.from_data('linearized_mesh', coors, None, conns, mat_ids,
                              self.domain.mesh.descs)

        return mesh, vdofs, levels
Beispiel #14
0
def create_expression_output(expression, name, primary_field_name,
                             fields, materials, variables,
                             functions=None, mode='eval', term_mode=None,
                             extra_args=None, verbose=True, kwargs=None,
                             min_level=0, max_level=1, eps=1e-4):
    """
    Create output mesh and data for the expression using the adaptive
    linearizer.

    Parameters
    ----------
    expression : str
        The expression to evaluate.
    name : str
        The name of the data.
    primary_field_name : str
        The name of field that defines the element groups and polynomial
        spaces.
    fields : dict
        The dictionary of fields used in `variables`.
    materials : Materials instance
        The materials used in the expression.
    variables : Variables instance
        The variables used in the expression.
    functions : Functions instance, optional
        The user functions for materials etc.
    mode : one of 'eval', 'el_avg', 'qp'
        The evaluation mode - 'qp' requests the values in quadrature points,
        'el_avg' element averages and 'eval' means integration over
        each term region.
    term_mode : str
        The term call mode - some terms support different call modes
        and depending on the call mode different values are
        returned.
    extra_args : dict, optional
        Extra arguments to be passed to terms in the expression.
    verbose : bool
        If False, reduce verbosity.
    kwargs : dict, optional
        The variables (dictionary of (variable name) : (Variable
        instance)) to be used in the expression.
    min_level : int
        The minimum required level of mesh refinement.
    max_level : int
        The maximum level of mesh refinement.
    eps : float
        The relative tolerance parameter of mesh adaptivity.

    Returns
    -------
    out : dict
        The output dictionary.
    """
    field = fields[primary_field_name]
    vertex_coors = field.coors[:field.n_vertex_dof, :]

    coors = []
    vdofs = []
    conns = []
    mat_ids = []
    levels = []
    offset = 0
    for ig, ap in field.aps.iteritems():
        ps = ap.interp.poly_spaces['v']
        gps = ap.interp.gel.interp.poly_spaces['v']
        group = field.domain.groups[ig]
        vertex_conn = ap.econn[:, :group.shape.n_ep]

        eval_dofs = get_eval_expression(expression, ig,
                                        fields, materials, variables,
                                        functions=functions,
                                        mode=mode, extra_args=extra_args,
                                        verbose=verbose, kwargs=kwargs)
        eval_coors = get_eval_coors(vertex_coors, vertex_conn, gps)

        (level, _coors, conn,
         _vdofs, _mat_ids) = create_output(eval_dofs, eval_coors,
                                           group.shape.n_el, ps,
                                           min_level=min_level,
                                           max_level=max_level, eps=eps)

        _mat_ids[:] = field.domain.mesh.mat_ids[ig][0]

        coors.append(_coors)
        vdofs.append(_vdofs)
        conns.append(conn + offset)
        mat_ids.append(_mat_ids)
        levels.append(level)

        offset += _coors.shape[0]

    coors = nm.concatenate(coors, axis=0)
    vdofs = nm.concatenate(vdofs, axis=0)
    mesh = Mesh.from_data('linearized_mesh', coors, None, conns, mat_ids,
                          field.domain.mesh.descs)

    out = {}
    out[name] = Struct(name='output_data', mode='vertex',
                       data=vdofs, var_name=name, dofs=None,
                       mesh=mesh, levels=levels)

    out = convert_complex_output(out)

    return out