Ejemplo n.º 1
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    def test_subdimmiddle_notparallel(self):
        """
        Tests application of an Operator consisting of a subdimension
        defined over different sub-regions, explicitly created through the
        use of SubDimensions.

        Different from ``test_subdimmiddle_parallel`` because an interior
        dimension cannot be evaluated in parallel.
        """
        grid = Grid(shape=(20, 20))
        x, y = grid.dimensions
        t = grid.stepping_dim
        thickness = 4

        u = TimeFunction(name='u',
                         save=None,
                         grid=grid,
                         space_order=0,
                         time_order=1)

        xi = SubDimension.middle(name='xi',
                                 parent=x,
                                 thickness_left=thickness,
                                 thickness_right=thickness)

        yi = SubDimension.middle(name='yi',
                                 parent=y,
                                 thickness_left=thickness,
                                 thickness_right=thickness)

        # flow dependencies in x and y which should force serial execution
        # in reverse direction
        centre = Eq(u[t + 1, xi, yi], u[t, xi, yi] + u[t + 1, xi + 1, yi + 1])
        u.data[0, 10, 10] = 1.0

        op = Operator([centre])

        iterations = FindNodes(Iteration).visit(op)
        assert all(i.is_Affine and i.is_Sequential for i in iterations
                   if i.dim == xi)
        assert all(i.is_Affine and i.is_Parallel for i in iterations
                   if i.dim == yi)

        op.apply(time_m=0, time_M=0)

        for i in range(4, 11):
            assert u.data[1, i, i] == 1.0
            u.data[1, i, i] = 0.0

        assert np.all(u.data[1, :] == 0)
Ejemplo n.º 2
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    def test_bcs(self):
        """
        Tests application of an Operator consisting of multiple equations
        defined over different sub-regions, explicitly created through the
        use of :class:`SubDimension`s.
        """
        grid = Grid(shape=(20, 20))
        x, y = grid.dimensions
        t = grid.stepping_dim
        thickness = 4

        u = TimeFunction(name='u',
                         save=None,
                         grid=grid,
                         space_order=0,
                         time_order=1)

        xleft = SubDimension.left(name='xleft', parent=x, thickness=thickness)
        xi = SubDimension.middle(name='xi',
                                 parent=x,
                                 thickness_left=thickness,
                                 thickness_right=thickness)
        xright = SubDimension.right(name='xright',
                                    parent=x,
                                    thickness=thickness)

        yi = SubDimension.middle(name='yi',
                                 parent=y,
                                 thickness_left=thickness,
                                 thickness_right=thickness)

        t_in_centre = Eq(u[t + 1, xi, yi], 1)
        leftbc = Eq(u[t + 1, xleft, yi], u[t + 1, xleft + 1, yi] + 1)
        rightbc = Eq(u[t + 1, xright, yi], u[t + 1, xright - 1, yi] + 1)

        op = Operator([t_in_centre, leftbc, rightbc])

        op.apply(time_m=1, time_M=1)

        assert np.all(u.data[0, :, 0:thickness] == 0.)
        assert np.all(u.data[0, :, -thickness:] == 0.)
        assert all(
            np.all(u.data[0, i, thickness:-thickness] == (thickness + 1 - i))
            for i in range(thickness))
        assert all(
            np.all(u.data[0, -i, thickness:-thickness] == (thickness + 2 - i))
            for i in range(1, thickness + 1))
        assert np.all(u.data[0, thickness:-thickness,
                             thickness:-thickness] == 1.)
Ejemplo n.º 3
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    def test_subdimmiddle_parallel(self):
        """
        Tests application of an Operator consisting of a subdimension
        defined over different sub-regions, explicitly created through the
        use of :class:`SubDimension`s.
        """
        grid = Grid(shape=(20, 20))
        x, y = grid.dimensions
        t = grid.stepping_dim
        thickness = 4

        u = TimeFunction(name='u',
                         save=None,
                         grid=grid,
                         space_order=0,
                         time_order=1)

        xi = SubDimension.middle(name='xi',
                                 parent=x,
                                 thickness_left=thickness,
                                 thickness_right=thickness)

        yi = SubDimension.middle(name='yi',
                                 parent=y,
                                 thickness_left=thickness,
                                 thickness_right=thickness)

        # a 5 point stencil that can be computed in parallel
        centre = Eq(
            u[t + 1, xi, yi], u[t, xi, yi] + u[t, xi - 1, yi] +
            u[t, xi + 1, yi] + u[t, xi, yi - 1] + u[t, xi, yi + 1])

        u.data[0, 10, 10] = 1.0

        op = Operator([centre])

        iterations = FindNodes(Iteration).visit(op)
        assert all(i.is_Affine and i.is_Parallel for i in iterations
                   if i.dim in [xi, yi])

        op.apply(time_m=0, time_M=0)

        assert np.all(u.data[1, 9:12, 10] == 1.0)
        assert np.all(u.data[1, 10, 9:12] == 1.0)

        # Other than those, it should all be 0
        u.data[1, 9:12, 10] = 0.0
        u.data[1, 10, 9:12] = 0.0
        assert np.all(u.data[1, :] == 0)
Ejemplo n.º 4
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    def test_subdimleft_parallel(self):
        """
        Tests application of an Operator consisting of a subdimension
        defined over different sub-regions, explicitly created through the
        use of :class:`SubDimension`s.

        This tests that flow direction is not being automatically inferred
        from whether the subdimension is on the left or right boundary.
        """
        grid = Grid(shape=(20, 20))
        x, y = grid.dimensions
        t = grid.stepping_dim
        thickness = 4

        u = TimeFunction(name='u', save=None, grid=grid, space_order=0, time_order=1)

        xl = SubDimension.left(name='xl', parent=x, thickness=thickness)

        yi = SubDimension.middle(name='yi', parent=y,
                                 thickness_left=thickness, thickness_right=thickness)

        # Can be done in parallel
        eq = Eq(u[t+1, xl, yi], u[t, xl, yi] + 1)

        op = Operator([eq])

        iterations = FindNodes(Iteration).visit(op)
        assert all(i.is_Affine and i.is_Parallel for i in iterations if i.dim in [xl, yi])

        op.apply(time_m=0, time_M=0)

        assert np.all(u.data[1, 0:thickness, 0:thickness] == 0)
        assert np.all(u.data[1, 0:thickness, -thickness:] == 0)
        assert np.all(u.data[1, 0:thickness, thickness:-thickness] == 1)
        assert np.all(u.data[1, thickness+1:, :] == 0)
Ejemplo n.º 5
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def test_sub_dimension():
    di = SubDimension.middle('di', Dimension(name='d'), 1, 1)

    pkl_di = pickle.dumps(di)
    new_di = pickle.loads(pkl_di)

    assert di.name == new_di.name
    assert di.dtype == new_di.dtype
    assert di.parent == new_di.parent
    assert di._thickness == new_di._thickness
    assert di._interval == new_di._interval
Ejemplo n.º 6
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def test_everything():
    nt = 50
    grid = Grid(shape=(6, 6))
    x, y = grid.dimensions
    time = grid.time_dim
    xi = SubDimension.middle(name='xi', parent=x, thickness_left=2, thickness_right=2)
    yi = SubDimension.middle(name='yi', parent=y, thickness_left=2, thickness_right=2)

    factor = Constant(name='factor', value=5, dtype=np.int32)
    t_sub = ConditionalDimension('t_sub', parent=time, factor=factor)
    save_shift = Constant(name='save_shift', dtype=np.int32)

    u = TimeFunction(name='u', grid=grid, time_order=0)
    u1 = TimeFunction(name='u', grid=grid, time_order=0)
    va = TimeFunction(name='va', grid=grid, time_order=0,
                      save=(int(nt//factor.data)), time_dim=t_sub)
    vb = TimeFunction(name='vb', grid=grid, time_order=0,
                      save=(int(nt//factor.data)), time_dim=t_sub)

    for i in range(va.save):
        va.data[i, :] = i
        vb.data[i, :] = i*2 - 1

    vas = va.subs(t_sub, t_sub - save_shift)
    vasb = va.subs(t_sub, t_sub - 1 - save_shift)
    vasf = va.subs(t_sub, t_sub + 1 - save_shift)

    eqns = [Eq(u.forward, u + (vasb + vas + vasf)*2. + vb)]

    eqns = [e.xreplace({x: xi, y: yi}) for e in eqns]

    op0 = Operator(eqns, opt='noop')
    op1 = Operator(eqns, opt='buffering')

    # Check generated code
    assert len([i for i in FindSymbols().visit(op1) if i.is_Array]) == 2

    op0.apply(time_m=15, time_M=35, save_shift=0)
    op1.apply(time_m=15, time_M=35, save_shift=0, u=u1)

    assert np.all(u.data == u1.data)
Ejemplo n.º 7
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    def test_sub_dimension(self):
        """
        Test that SubDimensions with same name but different attributes do not
        alias to the same SubDimension. Conversely, if the name and the attributes
        are the same, they must alias to the same SubDimension.
        """
        x = Dimension('x')
        xi0 = SubDimension.middle('xi', x, 1, 1)
        xi1 = SubDimension.middle('xi', x, 1, 1)
        assert xi0 is xi1

        xl0 = SubDimension.left('xl', x, 2)
        xl1 = SubDimension.left('xl', x, 2)
        assert xl0 is xl1
        xl2asxi = SubDimension.left('xi', x, 2)
        assert xl2asxi is not xl1
        assert xl2asxi is not xi1

        xr0 = SubDimension.right('xr', x, 1)
        xr1 = SubDimension.right('xr', x, 1)
        assert xr0 is xr1
Ejemplo n.º 8
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def test_sub_dimension_cache():
    """
    Test that SubDimensions with same name but different attributes do not
    alias to the same SubDimension. Conversely, if the name and the attributes
    are the same, they must alias to the same SubDimension.
    """
    x = Dimension('x')
    xi0 = SubDimension.middle('xi', x, 1, 1)
    xi1 = SubDimension.middle('xi', x, 1, 1)
    assert xi0 is xi1

    xl0 = SubDimension.left('xl', x, 2)
    xl1 = SubDimension.left('xl', x, 2)
    assert xl0 is xl1
    xl2asxi = SubDimension.left('xi', x, 2)
    assert xl2asxi is not xl1
    assert xl2asxi is not xi1

    xr0 = SubDimension.right('xr', x, 1)
    xr1 = SubDimension.right('xr', x, 1)
    assert xr0 is xr1
Ejemplo n.º 9
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    def test_save_w_subdims(self):
        nt = 10
        grid = Grid(shape=(10, 10))
        x, y = grid.dimensions
        time_dim = grid.time_dim
        xi = SubDimension.middle(name='xi',
                                 parent=x,
                                 thickness_left=3,
                                 thickness_right=3)
        yi = SubDimension.middle(name='yi',
                                 parent=y,
                                 thickness_left=3,
                                 thickness_right=3)

        factor = Constant(name='factor', value=2, dtype=np.int32)
        time_sub = ConditionalDimension(name="time_sub",
                                        parent=time_dim,
                                        factor=factor)

        u = TimeFunction(name='u', grid=grid)
        usave = TimeFunction(name='usave',
                             grid=grid,
                             time_order=0,
                             save=int(nt // factor.data),
                             time_dim=time_sub)

        eqns = [Eq(u.forward, u + 1), Eq(usave, u.forward)]
        eqns = [e.xreplace({x: xi, y: yi}) for e in eqns]

        op = Operator(eqns, opt=('buffering', 'tasking', 'orchestrate'))

        op.apply(time_M=nt - 1)

        for i in range(usave.save):
            assert np.all(usave.data[i, 3:-3, 3:-3] == 2 * i + 1)
            assert np.all(usave.data[i, :3, :] == 0)
            assert np.all(usave.data[i, -3:, :] == 0)
            assert np.all(usave.data[i, :, :3] == 0)
            assert np.all(usave.data[i, :, -3:] == 0)
Ejemplo n.º 10
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    def test_expandingbox_like(self):
        """
        Make sure SubDimensions aren't an obstacle to expanding boxes.
        """
        grid = Grid(shape=(8, 8))
        x, y = grid.dimensions

        u = TimeFunction(name='u', grid=grid)
        xi = SubDimension.middle(name='xi',
                                 parent=x,
                                 thickness_left=2,
                                 thickness_right=2)
        yi = SubDimension.middle(name='yi',
                                 parent=y,
                                 thickness_left=2,
                                 thickness_right=2)

        eqn = Eq(u.forward, u + 1)
        eqn = eqn.subs({x: xi, y: yi})

        op = Operator(eqn)

        op.apply(time=3,
                 x_m=2,
                 x_M=5,
                 y_m=2,
                 y_M=5,
                 xi_ltkn=0,
                 xi_rtkn=0,
                 yi_ltkn=0,
                 yi_rtkn=0)

        assert np.all(u.data[0, 2:-2, 2:-2] == 4.)
        assert np.all(u.data[1, 2:-2, 2:-2] == 3.)
        assert np.all(u.data[:, :2] == 0.)
        assert np.all(u.data[:, -2:] == 0.)
        assert np.all(u.data[:, :, :2] == 0.)
        assert np.all(u.data[:, :, -2:] == 0.)
Ejemplo n.º 11
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    def test_subdimensions(self):
        nt = 10
        grid = Grid(shape=(10, 10, 10))
        x, y, z = grid.dimensions
        xi = SubDimension.middle(name='xi', parent=x, thickness_left=2, thickness_right=2)
        yi = SubDimension.middle(name='yi', parent=y, thickness_left=2, thickness_right=2)
        zi = SubDimension.middle(name='zi', parent=z, thickness_left=2, thickness_right=2)

        u = TimeFunction(name='u', grid=grid, save=nt)
        u1 = TimeFunction(name='u', grid=grid, save=nt)

        eqn = Eq(u.forward, u + 1).xreplace({x: xi, y: yi, z: zi})

        op0 = Operator(eqn, opt='noop')
        op1 = Operator(eqn, opt='buffering')

        # Check generated code
        assert len(retrieve_iteration_tree(op1)) == 2
        assert len([i for i in FindSymbols().visit(op1) if i.is_Array]) == 1

        op0.apply(time_M=nt-2)
        op1.apply(time_M=nt-2, u=u1)

        assert np.all(u.data == u1.data)
Ejemplo n.º 12
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    def test_symbolic_size(self):
        """Check the symbolic size of all possible SubDimensions is as expected."""
        grid = Grid(shape=(4,))
        x, = grid.dimensions
        thickness = 4

        xleft = SubDimension.left(name='xleft', parent=x, thickness=thickness)
        assert xleft.symbolic_size == xleft.thickness.left[0]

        xi = SubDimension.middle(name='xi', parent=x,
                                 thickness_left=thickness, thickness_right=thickness)
        assert xi.symbolic_size == (x.symbolic_max - x.symbolic_min -
                                    xi.thickness.left[0] - xi.thickness.right[0] + 1)

        xright = SubDimension.right(name='xright', parent=x, thickness=thickness)
        assert xright.symbolic_size == xright.thickness.right[0]
Ejemplo n.º 13
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    def test_subdimleft_notparallel(self):
        """
        Tests application of an Operator consisting of a subdimension
        defined over different sub-regions, explicitly created through the
        use of :class:`SubDimension`s.

        This tests that flow direction is not being automatically inferred
        from whether the subdimension is on the left or right boundary.
        """
        grid = Grid(shape=(20, 20))
        x, y = grid.dimensions
        t = grid.stepping_dim
        thickness = 4

        u = TimeFunction(name='u',
                         save=None,
                         grid=grid,
                         space_order=1,
                         time_order=0)

        xl = SubDimension.left(name='xl', parent=x, thickness=thickness)

        yi = SubDimension.middle(name='yi',
                                 parent=y,
                                 thickness_left=thickness,
                                 thickness_right=thickness)

        # Flows inward (i.e. forward) rather than outward
        eq = Eq(u[t + 1, xl, yi], u[t + 1, xl - 1, yi] + 1)

        op = Operator([eq])

        iterations = FindNodes(Iteration).visit(op)
        assert all(i.is_Affine and i.is_Sequential for i in iterations
                   if i.dim == xl)
        assert all(i.is_Affine and i.is_Parallel for i in iterations
                   if i.dim == yi)

        op.apply(time_m=1, time_M=1)

        assert all(
            np.all(u.data[0, :thickness, thickness + i] == [1, 2, 3, 4])
            for i in range(12))
        assert np.all(u.data[0, thickness:] == 0)
        assert np.all(u.data[0, :, thickness + 12:] == 0)
Ejemplo n.º 14
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    def test_index_mode_detection(self, indexed, expected):
        """
        Test detection of IterationInstance access modes (AFFINE vs IRREGULAR).

        Proper detection of access mode is a prerequisite to any sort of
        data dependence analysis.
        """
        grid = Grid(shape=(4, 4, 4))
        x, y, z = grid.dimensions  # noqa

        sx = SubDimension.middle('sx', x, 1, 1)  # noqa

        u = Function(name='u', grid=grid)  # noqa
        c = Constant(name='c')  # noqa
        sc = Scalar(name='sc', is_const=True)  # noqa
        s = Scalar(name='s')  # noqa

        ii = IterationInstance(eval(indexed))
        assert ii.index_mode == expected
Ejemplo n.º 15
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    def test_bcs_basic(self):
        """
        Test MPI in presence of boundary condition loops. Here, no halo exchange
        is expected (as there is no stencil in the computed expression) but we
        check that:

            * the left BC loop is computed by the leftmost rank only
            * the right BC loop is computed by the rightmost rank only
        """
        grid = Grid(shape=(20, ))
        x = grid.dimensions[0]
        t = grid.stepping_dim

        thickness = 4

        u = TimeFunction(name='u', grid=grid, time_order=1)

        xleft = SubDimension.left(name='xleft', parent=x, thickness=thickness)
        xi = SubDimension.middle(name='xi',
                                 parent=x,
                                 thickness_left=thickness,
                                 thickness_right=thickness)
        xright = SubDimension.right(name='xright',
                                    parent=x,
                                    thickness=thickness)

        t_in_centre = Eq(u[t + 1, xi], 1)
        leftbc = Eq(u[t + 1, xleft], u[t + 1, xleft + 1] + 1)
        rightbc = Eq(u[t + 1, xright], u[t + 1, xright - 1] + 1)

        op = Operator([t_in_centre, leftbc, rightbc])

        op.apply(time_m=1, time_M=1)

        glb_pos_map = u.grid.distributor.glb_pos_map
        if LEFT in glb_pos_map[x]:
            assert np.all(u.data_ro_domain[0, thickness:] == 1.)
            assert np.all(
                u.data_ro_domain[0, :thickness] == range(thickness + 1, 1, -1))
        else:
            assert np.all(u.data_ro_domain[0, :-thickness] == 1.)
            assert np.all(
                u.data_ro_domain[0, -thickness:] == range(2, thickness + 2))
Ejemplo n.º 16
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    def test_index_mode_detection(self, indexed, expected):
        """
        Test detection of IterationInstance access modes (AFFINE vs IRREGULAR).

        Proper detection of access mode is a prerequisite to any sort of
        data dependence analysis.
        """
        grid = Grid(shape=(4, 4, 4))
        x, y, z = grid.dimensions  # noqa

        sx = SubDimension.middle('sx', x, 1, 1)  # noqa

        u = Function(name='u', grid=grid)  # noqa
        c = Constant(name='c')  # noqa
        sc = Scalar(name='sc', is_const=True)  # noqa
        s = Scalar(name='s')  # noqa

        ii = IterationInstance(eval(indexed))
        assert ii.index_mode == expected
Ejemplo n.º 17
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    def test_subdim_middle(self):
        """
        Tests that instantiating SubDimensions using the classmethod
        constructors works correctly.
        """
        grid = Grid(shape=(4, 4, 4))
        x, y, z = grid.dimensions
        t = grid.stepping_dim  # noqa

        u = TimeFunction(name='u', grid=grid)  # noqa
        xi = SubDimension.middle(name='xi', parent=x,
                                 thickness_left=1,
                                 thickness_right=1)
        eqs = [Eq(u.forward, u + 1)]
        eqs = [e.subs(x, xi) for e in eqs]

        op = Operator(eqs)

        u.data[:] = 1.0
        op.apply(time_M=1)
        assert np.all(u.data[1, 0, :, :] == 1)
        assert np.all(u.data[1, -1, :, :] == 1)
        assert np.all(u.data[1, 1:3, :, :] == 2)
Ejemplo n.º 18
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    def test_nontrivial_operator(self):
        """
        Test MPI in a non-trivial scenario: ::

            * 9 processes logically organised in a 3x3 cartesian grid (as opposed to
              most tests in this module, which only use 2 or 4 processed);
            * star-like stencil expression;
            * non-trivial Higdon-like BCs;
            * simultaneous presence of TimeFunction(grid), Function(grid), and
              Function(dimensions)
        """
        size_x, size_y = 9, 9
        tkn = 2

        # Grid and Dimensions
        grid = Grid(shape=(
            size_x,
            size_y,
        ))
        x, y = grid.dimensions
        t = grid.stepping_dim

        # SubDimensions to implement BCs
        xl, yl = [SubDimension.left('%sl' % d.name, d, tkn) for d in [x, y]]
        xi, yi = [
            SubDimension.middle('%si' % d.name, d, tkn, tkn) for d in [x, y]
        ]
        xr, yr = [SubDimension.right('%sr' % d.name, d, tkn) for d in [x, y]]

        # Functions
        u = TimeFunction(name='f', grid=grid)
        m = Function(name='m', grid=grid)
        c = Function(name='c', grid=grid, dimensions=(x, ), shape=(size_x, ))

        # Data initialization
        u.data_with_halo[:] = 0.
        m.data_with_halo[:] = 1.
        c.data_with_halo[:] = 0.

        # Equations
        c_init = Eq(c, 1.)
        eqn = Eq(u[t + 1, xi, yi], u[t, xi, yi] + m[xi, yi] + c[xi] + 1.)
        bc_left = Eq(u[t + 1, xl, yi], u[t + 1, xl + 1, yi] + 1.)
        bc_right = Eq(u[t + 1, xr, yi], u[t + 1, xr - 1, yi] + 1.)
        bc_top = Eq(u[t + 1, xi, yl], u[t + 1, xi, yl + 1] + 1.)
        bc_bottom = Eq(u[t + 1, xi, yr], u[t + 1, xi, yr - 1] + 1.)

        op = Operator([c_init, eqn, bc_left, bc_right, bc_top, bc_bottom])
        op.apply(time=0)

        # Expected (global view):
        # 0 0 5 5 5 5 5 0 0
        # 0 0 4 4 4 4 4 0 0
        # 5 4 3 3 3 3 3 4 5
        # 5 4 3 3 3 3 3 4 5
        # 5 4 3 3 3 3 3 4 5
        # 5 4 3 3 3 3 3 4 5
        # 0 0 4 4 4 4 4 0 0
        # 0 0 5 5 5 5 5 0 0

        assert np.all(u.data_ro_domain[0] == 0)  # The write occures at t=1

        glb_pos_map = u.grid.distributor.glb_pos_map
        # Check cornes
        if LEFT in glb_pos_map[x] and LEFT in glb_pos_map[y]:
            assert np.all(
                u.data_ro_domain[1] == [[0, 0, 5], [0, 0, 4], [5, 4, 3]])
        elif LEFT in glb_pos_map[x] and RIGHT in glb_pos_map[y]:
            assert np.all(
                u.data_ro_domain[1] == [[5, 0, 0], [4, 0, 0], [3, 4, 5]])
        elif RIGHT in glb_pos_map[x] and LEFT in glb_pos_map[y]:
            assert np.all(
                u.data_ro_domain[1] == [[5, 4, 3], [0, 0, 4], [0, 0, 5]])
        elif RIGHT in glb_pos_map[x] and RIGHT in glb_pos_map[y]:
            assert np.all(
                u.data_ro_domain[1] == [[3, 4, 5], [4, 0, 0], [5, 0, 0]])
        # Check sides
        if not glb_pos_map[x] and LEFT in glb_pos_map[y]:
            assert np.all(
                u.data_ro_domain[1] == [[5, 4, 3], [5, 4, 3], [5, 4, 3]])
        elif not glb_pos_map[x] and RIGHT in glb_pos_map[y]:
            assert np.all(
                u.data_ro_domain[1] == [[3, 4, 5], [3, 4, 5], [3, 4, 5]])
        elif LEFT in glb_pos_map[x] and not glb_pos_map[y]:
            assert np.all(
                u.data_ro_domain[1] == [[5, 5, 5], [4, 4, 4], [3, 3, 3]])
        elif RIGHT in glb_pos_map[x] and not glb_pos_map[y]:
            assert np.all(
                u.data_ro_domain[1] == [[3, 3, 3], [4, 4, 4], [5, 5, 5]])
        # Check center
        if not glb_pos_map[x] and not glb_pos_map[y]:
            assert np.all(u.data_ro_domain[1] == 3)