Exemple #1
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def test_element_setitem_single():
    H = odl.ProductSpace(odl.rn(1), odl.rn(2))

    x1 = H[0].element([0])
    x2 = H[1].element([1, 2])
    x = H.element([x1, x2])

    x1_1 = H[0].element([1])
    x[-2] = x1_1
    assert x[-2] is x1_1

    x2_1 = H[1].element([3, 4])
    x[-1] = x2_1
    assert x[-1] is x2_1

    x1_2 = H[0].element([5])
    x[0] = x1_2

    x2_2 = H[1].element([3, 4])
    x[1] = x2_2
    assert x[1] is x2_2

    with pytest.raises(IndexError):
        x[-3] = x2
        x[2] = x1
def test_fixed_disp_init():
    """Verify that the init method and checks work properly."""
    space = odl.uniform_discr(0, 1, 5)
    disp_field = space.tangent_bundle.element(
        disp_field_factory(space.ndim))

    # Valid input
    print(LinDeformFixedDisp(disp_field))
    print(LinDeformFixedDisp(disp_field, templ_space=space))

    # Non-valid input
    with pytest.raises(TypeError):  # displacement not ProductSpaceElement
        LinDeformFixedDisp(space.one())
    with pytest.raises(TypeError):  # templ_space not DiscreteLp
        LinDeformFixedDisp(disp_field, space.tangent_bundle)
    with pytest.raises(TypeError):  # templ_space not a power space
        bad_pspace = odl.ProductSpace(space, odl.rn(3))
        LinDeformFixedDisp(disp_field, bad_pspace)
    with pytest.raises(TypeError):  # templ_space not based on DiscreteLp
        bad_pspace = odl.ProductSpace(odl.rn(2), 1)
        LinDeformFixedDisp(disp_field, bad_pspace)
    with pytest.raises(TypeError):  # wrong dtype on templ_space
        wrong_dtype = odl.ProductSpace(space.astype(complex), 1)
        LinDeformFixedDisp(disp_field, wrong_dtype)
    with pytest.raises(ValueError):  # vector field spaces don't match
        bad_space = odl.uniform_discr(0, 1, 10)
        LinDeformFixedDisp(disp_field, bad_space)
Exemple #3
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def test_ufuncs():
    # Cannot use fixture due to bug in pytest
    H = odl.ProductSpace(odl.rn(1), odl.rn(2))

    # one arg
    x = H.element([[-1], [-2, -3]])

    z = x.ufunc.absolute()
    assert all_almost_equal(z, [[1], [2, 3]])

    # one arg with out
    x = H.element([[-1], [-2, -3]])
    y = H.element()

    z = x.ufunc.absolute(out=y)
    assert y is z
    assert all_almost_equal(z, [[1], [2, 3]])

    # Two args
    x = H.element([[1], [2, 3]])
    y = H.element([[4], [5, 6]])
    w = H.element()

    z = x.ufunc.add(y)
    assert all_almost_equal(z, [[5], [7, 9]])

    # Two args with out
    x = H.element([[1], [2, 3]])
    y = H.element([[4], [5, 6]])
    w = H.element()

    z = x.ufunc.add(y, out=w)
    assert w is z
    assert all_almost_equal(z, [[5], [7, 9]])
Exemple #4
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def test_element_setitem_fancy():
    """Test assignment of pspace parts with lists."""
    pspace = odl.ProductSpace(odl.rn(1), odl.rn(2), odl.rn(3))

    x0 = pspace[0].element([0])
    x1 = pspace[1].element([1, 2])
    x2 = pspace[2].element([3, 4, 5])
    x = pspace.element([x0, x1, x2])
    old_x0 = x[0]
    old_x2 = x[2]

    # Check that values are set, but identity is preserved
    new_x0 = pspace[0].element([6])
    new_x2 = pspace[2].element([7, 8, 9])
    x[[0, 2]] = pspace[[0, 2]].element([new_x0, new_x2])
    assert x[[0, 2]][0] is old_x0
    assert x[[0, 2]][0] == new_x0
    assert x[[0, 2]][1] is old_x2
    assert x[[0, 2]][1] == new_x2

    # Set values with sequences of scalars
    x[[0, 2]] = [-1, -2]
    assert x[[0, 2]][0] is old_x0
    assert all_equal(x[[0, 2]][0], [-1])
    assert x[[0, 2]][1] is old_x2
    assert all_equal(x[[0, 2]][1], [-2, -2, -2])
Exemple #5
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def test_init(exponent):
    # Validate that the different init patterns work and do not crash.
    space = odl.FunctionSpace(odl.IntervalProd(0, 1))
    part = odl.uniform_partition_fromintv(space.domain, 10)
    rn = odl.rn(10, exponent=exponent)
    odl.DiscreteLp(space, part, rn, exponent=exponent)
    odl.DiscreteLp(space, part, rn, exponent=exponent, interp='linear')

    # Normal discretization of unit interval with complex
    complex_space = odl.FunctionSpace(odl.IntervalProd(0, 1),
                                      field=odl.ComplexNumbers())

    cn = odl.cn(10, exponent=exponent)
    odl.DiscreteLp(complex_space, part, cn, exponent=exponent)

    space = odl.FunctionSpace(odl.IntervalProd([0, 0], [1, 1]))
    part = odl.uniform_partition_fromintv(space.domain, (10, 10))
    rn = odl.rn(100, exponent=exponent)
    odl.DiscreteLp(space, part, rn, exponent=exponent,
                   interp=['nearest', 'linear'])

    # Real space should not work with complex
    with pytest.raises(ValueError):
        odl.DiscreteLp(space, part, cn)

    # Complex space should not work with reals
    with pytest.raises(ValueError):
        odl.DiscreteLp(complex_space, part, rn)

    # Wrong size of underlying space
    rn_wrong_size = odl.rn(20)
    with pytest.raises(ValueError):
        odl.DiscreteLp(space, part, rn_wrong_size)
Exemple #6
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def test_element_setitem_single():
    """Test assignment of pspace parts with single indices."""
    pspace = odl.ProductSpace(odl.rn(1), odl.rn(2))

    x0 = pspace[0].element([0])
    x1 = pspace[1].element([1, 2])
    x = pspace.element([x0, x1])
    old_x0 = x[0]
    old_x1 = x[1]

    # Check that values are set, but identity is preserved
    new_x0 = pspace[0].element([1])
    x[-2] = new_x0
    assert x[-2] == new_x0
    assert x[-2] is old_x0

    new_x1 = pspace[1].element([3, 4])
    x[-1] = new_x1
    assert x[-1] == new_x1
    assert x[-1] is old_x1

    # Set values with scalars
    x[1] = -1
    assert all_equal(x[1], [-1, -1])
    assert x[1] is old_x1

    # Check that out-of-bounds indices raise IndexError
    with pytest.raises(IndexError):
        x[-3] = x1
    with pytest.raises(IndexError):
        x[2] = x0
Exemple #7
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def test_reductions():
    H = odl.ProductSpace(odl.rn(1), odl.rn(2))
    x = H.element([[1], [2, 3]])
    assert x.ufunc.sum() == 6.0
    assert x.ufunc.prod() == 6.0
    assert x.ufunc.min() == 1.0
    assert x.ufunc.max() == 3.0
Exemple #8
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def test_custom_funcs():
    # Checking the standard 1-norm and standard inner product, just to
    # see that the functions are handled correctly.

    r2 = odl.rn(2)
    r2x = r2.element([1, -1])
    r2y = r2.element([-2, 3])
    # inner = -5, dist = 5, norms = (sqrt(2), sqrt(13))

    r3 = odl.rn(3)
    r3x = r3.element([3, 4, 4])
    r3y = r3.element([1, -2, 1])
    # inner = -1, dist = 7, norms = (sqrt(41), sqrt(6))

    pspace_2 = odl.ProductSpace(r2, r3, exponent=2.0)
    x = pspace_2.element((r2x, r3x))
    y = pspace_2.element((r2y, r3y))

    pspace_custom = odl.ProductSpace(r2, r3, inner=custom_inner)
    xc = pspace_custom.element((r2x, r3x))
    yc = pspace_custom.element((r2y, r3y))
    assert almost_equal(x.inner(y), xc.inner(yc))

    pspace_1 = odl.ProductSpace(r2, r3, exponent=1.0)
    x = pspace_1.element((r2x, r3x))
    y = pspace_1.element((r2y, r3y))

    pspace_custom = odl.ProductSpace(r2, r3, norm=custom_norm)
    xc = pspace_custom.element((r2x, r3x))
    assert almost_equal(x.norm(), xc.norm())

    pspace_custom = odl.ProductSpace(r2, r3, dist=custom_dist)
    xc = pspace_custom.element((r2x, r3x))
    yc = pspace_custom.element((r2y, r3y))
    assert almost_equal(x.dist(y), xc.dist(yc))

    with pytest.raises(TypeError):
        odl.ProductSpace(r2, r3, a=1)  # extra keyword argument

    with pytest.raises(ValueError):
        odl.ProductSpace(r2, r3, norm=custom_norm, inner=custom_inner)

    with pytest.raises(ValueError):
        odl.ProductSpace(r2, r3, dist=custom_dist, inner=custom_inner)

    with pytest.raises(ValueError):
        odl.ProductSpace(r2, r3, norm=custom_norm, dist=custom_dist)

    with pytest.raises(ValueError):
        odl.ProductSpace(r2, r3, norm=custom_norm, exponent=1.0)

    with pytest.raises(ValueError):
        odl.ProductSpace(r2, r3, norm=custom_norm, weight=2.0)

    with pytest.raises(ValueError):
        odl.ProductSpace(r2, r3, dist=custom_dist, weight=2.0)

    with pytest.raises(ValueError):
        odl.ProductSpace(r2, r3, inner=custom_inner, weight=2.0)
Exemple #9
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    def __init__(self, matrix, domain=None, range=None):
        dom = (odl.rn(matrix.shape[1])
               if domain is None else domain)
        ran = (odl.rn(matrix.shape[0])
               if range is None else range)

        super().__init__(dom, ran)
        self.matrix = matrix
Exemple #10
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def test_getitem_fancy():
    r1 = odl.rn(1)
    r2 = odl.rn(2)
    r3 = odl.rn(3)
    H = odl.ProductSpace(r1, r2, r3)

    assert H[[0, 2]] == odl.ProductSpace(r1, r3)
    assert H[[0, 2]][0] is r1
    assert H[[0, 2]][1] is r3
Exemple #11
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def test_getitem_slice():
    r1 = odl.rn(1)
    r2 = odl.rn(2)
    r3 = odl.rn(3)
    H = odl.ProductSpace(r1, r2, r3)

    assert H[:2] == odl.ProductSpace(r1, r2)
    assert H[:2][0] is r1
    assert H[:2][1] is r2

    assert H[3:] == odl.ProductSpace(field=r1.field)
Exemple #12
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def test_element_getitem_fancy():
    H = odl.ProductSpace(odl.rn(1), odl.rn(2), odl.rn(3))

    x1 = H[0].element([0])
    x2 = H[1].element([1, 2])
    x3 = H[2].element([3, 4, 5])
    x = H.element([x1, x2, x3])

    assert x[[0, 2]].space == H[[0, 2]]
    assert x[[0, 2]][0] is x1
    assert x[[0, 2]][1] is x3
Exemple #13
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def test_element_getitem_slice():
    H = odl.ProductSpace(odl.rn(1), odl.rn(2), odl.rn(3))

    x0 = H[0].element([0])
    x1 = H[1].element([1, 2])
    x2 = H[2].element([3, 4, 5])
    x = H.element([x0, x1, x2])

    assert x[:2].space == H[:2]
    assert x[:2][0] is x0
    assert x[:2][1] is x1
Exemple #14
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def test_getitem_single():
    r1 = odl.rn(1)
    r2 = odl.rn(2)
    H = odl.ProductSpace(r1, r2)

    assert H[-2] is r1
    assert H[-1] is r2
    assert H[0] is r1
    assert H[1] is r2
    with pytest.raises(IndexError):
        H[-3]
        H[2]
Exemple #15
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def test_mixed_space():
    """Verify that a mixed productspace is handled properly."""
    r2_1 = odl.rn(2, dtype='float64')
    r2_2 = odl.rn(2, dtype='float32')
    pspace = odl.ProductSpace(r2_1, r2_2)

    assert not pspace.is_power_space
    assert pspace.spaces[0] is r2_1
    assert pspace.spaces[1] is r2_2

    # dtype not well defined for this space
    with pytest.raises(AttributeError):
        pspace.dtype
Exemple #16
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def test_element_setitem_slice():
    H = odl.ProductSpace(odl.rn(1), odl.rn(2), odl.rn(3))

    x1 = H[0].element([0])
    x2 = H[1].element([1, 2])
    x3 = H[2].element([3, 4, 5])
    x = H.element([x1, x2, x3])

    x1_new = H[0].element([6])
    x2_new = H[1].element([7, 8])
    x[:2] = H[:2].element([x1_new, x2_new])
    assert x[:2][0] is x1_new
    assert x[:2][1] is x2_new
Exemple #17
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def test_element_setitem_fancy():
    H = odl.ProductSpace(odl.rn(1), odl.rn(2), odl.rn(3))

    x1 = H[0].element([0])
    x2 = H[1].element([1, 2])
    x3 = H[2].element([3, 4, 5])
    x = H.element([x1, x2, x3])

    x1_new = H[0].element([6])
    x3_new = H[2].element([7, 8, 9])
    x[[0, 2]] = H[[0, 2]].element([x1_new, x3_new])
    assert x[[0, 2]][0] is x1_new
    assert x[[0, 2]][1] is x3_new
Exemple #18
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def test_element_getitem_single():
    H = odl.ProductSpace(odl.rn(1), odl.rn(2))

    x1 = H[0].element([0])
    x2 = H[1].element([1, 2])
    x = H.element([x1, x2])

    assert x[-2] is x1
    assert x[-1] is x2
    assert x[0] is x1
    assert x[1] is x2
    with pytest.raises(IndexError):
        x[-3]
        x[2]
Exemple #19
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def test_element_equals():
    H = odl.ProductSpace(odl.rn(1), odl.rn(2))
    x = H.element([[0], [1, 2]])

    assert x != 0  # test == not always true
    assert x == x

    x_2 = H.element([[0], [1, 2]])
    assert x == x_2

    x_3 = H.element([[3], [1, 2]])
    assert x != x_3

    x_4 = H.element([[0], [1, 3]])
    assert x != x_4
Exemple #20
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def test_nonlinear_functional():
    r3 = odl.rn(3)
    x = r3.element([1, 2, 3])

    op = SumSquaredFunctional(r3)

    assert almost_equal(op(x), np.sum(x**2))
Exemple #21
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def test_functional():
    r3 = odl.rn(3)
    x = r3.element([1, 2, 3])

    op = SumFunctional(r3)

    assert op(x) == 6
Exemple #22
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def test_arithmetic():
    """Test that all standard arithmetic works."""
    space = odl.rn(3)

    # Create elements needed for later
    functional = odl.solvers.L2Norm(space).translated([1, 2, 3])
    functional2 = odl.solvers.L2NormSquared(space)
    operator = odl.IdentityOperator(space) - space.element([4, 5, 6])
    x = noise_element(functional.domain)
    y = noise_element(functional.domain)
    scalar = np.pi

    # Simple tests here, more in depth comes later
    assert functional(x) == functional(x)
    assert functional(x) != functional2(x)
    assert (scalar * functional)(x) == scalar * functional(x)
    assert (scalar * (scalar * functional))(x) == scalar**2 * functional(x)
    assert (functional * scalar)(x) == functional(scalar * x)
    assert ((functional * scalar) * scalar)(x) == functional(scalar**2 * x)
    assert (functional + functional2)(x) == functional(x) + functional2(x)
    assert (functional - functional2)(x) == functional(x) - functional2(x)
    assert (functional * operator)(x) == functional(operator(x))
    assert all_almost_equal((y * functional)(x), y * functional(x))
    assert all_almost_equal((y * (y * functional))(x), (y * y) * functional(x))
    assert all_almost_equal((functional * y)(x), functional(y * x))
    assert all_almost_equal(((functional * y) * y)(x), functional((y * y) * x))
def test_primal_dual_with_li():
    """Test for the forward-backward solver with infimal convolution.

    The test is done by minimizing the functional ``(g @ l)(x)``, where

        ``(g @ l)(x) = inf_y { g(y) + l(x - y) }``,

    g is the indicator function on [-3, -1], and l(x) = 1/2||x||_2^2.
    The optimal solution to this problem is given by x in [-3, -1].
    """
    # Parameter values for the box constraint
    upper_lim = -1
    lower_lim = -3

    space = odl.rn(1)

    lin_ops = [odl.IdentityOperator(space)]
    g = [odl.solvers.IndicatorBox(space, lower=lower_lim, upper=upper_lim)]
    f = odl.solvers.ZeroFunctional(space)
    l = [odl.solvers.L2NormSquared(space)]

    # Centering around a point further away from [-3,-1].
    x = space.element(10)

    douglas_rachford_pd(x, f, g, lin_ops, tau=0.5, sigma=[1.0], niter=20, l=l)

    assert lower_lim - 10 ** -LOW_ACCURACY <= float(x)
    assert float(x) <= upper_lim + 10 ** -LOW_ACCURACY
Exemple #24
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def test_power_method_opnorm_exceptions():
    # Test the exceptions

    space = odl.rn(2)
    op = odl.IdentityOperator(space)

    with pytest.raises(ValueError):
        # Too small number of iterates
        power_method_opnorm(op, maxiter=0)

    with pytest.raises(ValueError):
        # Negative number of iterates
        power_method_opnorm(op, maxiter=-5)

    with pytest.raises(ValueError):
        # Input vector is zero
        power_method_opnorm(op, maxiter=2, xstart=space.zero())

    with pytest.raises(ValueError):
        # Input vector in the nullspace
        op = odl.MatrixOperator([[0., 1.], [0., 0.]])

        power_method_opnorm(op, maxiter=2, xstart=op.domain.one())

    with pytest.raises(ValueError):
        # Uneven number of iterates for non square operator
        op = odl.MatrixOperator([[1., 2., 3.], [4., 5., 6.]])

        power_method_opnorm(op, maxiter=1, xstart=op.domain.one())
Exemple #25
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def test_functional_scale():
    r3 = odl.rn(3)

    Aop = SumFunctional(r3)
    x = r3.element([1, 2, 3])
    y = 1

    # Test a range of scalars (scalar multiplication could implement
    # optimizations for (-1, 0, 1).
    scalars = [-1.432, -1, 0, 1, 3.14]
    for scale in scalars:
        C = OperatorRightScalarMult(Aop, scale)

        assert C.is_linear
        assert C.adjoint.is_linear

        assert C(x) == scale * np.sum(x)
        assert all_almost_equal(C.adjoint(y), scale * y * np.ones(3))
        assert all_almost_equal(C.adjoint.adjoint(x), C(x))

        # Using operator overloading
        assert (scale * Aop)(x) == scale * np.sum(x)
        assert (Aop * scale)(x) == scale * np.sum(x)
        assert all_almost_equal((scale * Aop).adjoint(y),
                                scale * y * np.ones(3))
        assert all_almost_equal((Aop * scale).adjoint(y),
                                scale * y * np.ones(3))
Exemple #26
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def test_element_1d(exponent):
    discr = odl.uniform_discr(0, 1, 3, impl='numpy', exponent=exponent)
    weight = 1.0 if exponent == float('inf') else discr.cell_volume
    dspace = odl.rn(3, exponent=exponent, weighting=weight)
    elem = discr.element()
    assert isinstance(elem, odl.DiscreteLpElement)
    assert elem.ntuple in dspace
Exemple #27
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def test_metric():
    H = odl.rn(2)
    v11 = H.element([1, 2])
    v12 = H.element([5, 3])

    v21 = H.element([1, 2])
    v22 = H.element([8, 9])

    # 1-norm
    HxH = odl.ProductSpace(H, H, exponent=1.0)
    w1 = HxH.element([v11, v12])
    w2 = HxH.element([v21, v22])
    assert almost_equal(HxH.dist(w1, w2),
                        H.dist(v11, v21) + H.dist(v12, v22))

    # 2-norm
    HxH = odl.ProductSpace(H, H, exponent=2.0)
    w1 = HxH.element([v11, v12])
    w2 = HxH.element([v21, v22])
    assert almost_equal(
        HxH.dist(w1, w2),
        (H.dist(v11, v21) ** 2 + H.dist(v12, v22) ** 2) ** (1 / 2.0))

    # inf norm
    HxH = odl.ProductSpace(H, H, exponent=float('inf'))
    w1 = HxH.element([v11, v12])
    w2 = HxH.element([v21, v22])
    assert almost_equal(
        HxH.dist(w1, w2),
        max(H.dist(v11, v21), H.dist(v12, v22)))
Exemple #28
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def test_pnorm(exponent):
    for fn in (odl.rn(3, exponent=exponent), odl.cn(3, exponent=exponent)):
        xarr, x = noise_elements(fn)
        correct_norm = np.linalg.norm(xarr, ord=exponent)

        assert almost_equal(fn.norm(x), correct_norm)
        assert almost_equal(x.norm(), correct_norm)
Exemple #29
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def test_getitem_single():
    r1 = odl.rn(1)
    r2 = odl.rn(2)
    H = odl.ProductSpace(r1, r2)

    assert H[-2] is r1
    assert H[-1] is r2
    assert H[0] is r1
    assert H[1] is r2
    with pytest.raises(IndexError):
        H[-3]
        H[2]

    assert H[(1, )] == r2
    with pytest.raises(IndexError):
        H[0, 1]
Exemple #30
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def test_element_getitem_multi():
    """Test element access with multiple indices."""
    pspace = odl.ProductSpace(odl.rn(1), odl.rn(2))
    pspace2 = odl.ProductSpace(pspace, 3)
    pspace3 = odl.ProductSpace(pspace2, 2)
    z = pspace3.element([[[[1], [2, 3]], [[4], [5, 6]], [[7], [8, 9]]],
                         [[[10], [12, 13]], [[14], [15, 16]], [[17], [18,
                                                                      19]]]])

    assert pspace3.shape == (2, 3, 2)
    assert z[0, 0, 0, 0] == 1
    assert all_equal(z[0, 0, 1], [2, 3])
    assert all_equal(z[0, 0], [[1], [2, 3]])
    assert all_equal(z[0, 1:], [[[4], [5, 6]], [[7], [8, 9]]])
    assert all_equal(z[0, 1:, 1], [[5, 6], [8, 9]])
    assert all_equal(z[0, 1:, :, 0], [[[4], [5]], [[7], [8]]])
Exemple #31
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def test_gradient_init():
    """Check initialization of ``Gradient``."""
    space = odl.uniform_discr([0, 0], [1, 1], (4, 5))
    vspace = space ** 2

    op = Gradient(space)
    assert repr(op) != ''
    op = Gradient(range=vspace)
    assert repr(op) != ''
    op = Gradient(space, range=space.astype('float32') ** 2)
    assert repr(op) != ''
    op = Gradient(space, method='central')
    assert repr(op) != ''
    op = Gradient(space, pad_const=1)
    assert repr(op) != ''
    op = Gradient(space, pad_mode='order1')
    assert repr(op) != ''

    with pytest.raises(TypeError):
        Gradient(odl.rn(1))

    with pytest.raises(TypeError):
        Gradient(space, range=space)

    with pytest.raises(ValueError):
        Gradient(space, range=space ** 3)
Exemple #32
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def test_divergence_init():
    """Check initialization of ``Divergence``."""
    space = odl.uniform_discr([0, 0], [1, 1], (4, 5))
    vspace = space ** 2

    op = Divergence(vspace)
    assert repr(op) != ''
    op = Divergence(range=space)
    assert repr(op) != ''
    op = Divergence(vspace, range=space.astype('float32'))
    assert repr(op) != ''
    op = Divergence(vspace, method='central')
    assert repr(op) != ''
    op = Divergence(vspace, pad_const=1)
    assert repr(op) != ''
    op = Divergence(vspace, pad_mode='order1')
    assert repr(op) != ''

    with pytest.raises(TypeError):
        Divergence(odl.rn(1) ** 2)

    with pytest.raises(TypeError):
        Divergence(vspace, range=vspace)

    with pytest.raises(ValueError):
        Divergence(space ** 3, range=space)
def space(request, tspace_impl):
    name = request.param.strip()

    if name == 'r10':
        return odl.rn(10, impl=tspace_impl)
    elif name == 'uniform_discr':
        return odl.uniform_discr(0, 1, 7, impl=tspace_impl)
Exemple #34
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def test_operators(arithmetic_op):
    # Test of the operators `+`, `-`, etc work as expected by numpy

    space = odl.rn(3)
    pspace = odl.ProductSpace(space, 2)

    # Interactions with scalars

    for scalar in [-31.2, -1, 0, 1, 2.13]:

        # Left op
        x_arr, x = noise_elements(pspace)
        if scalar == 0 and arithmetic_op in [operator.truediv,
                                             operator.itruediv]:
            # Check for correct zero division behaviour
            with pytest.raises(ZeroDivisionError):
                y = arithmetic_op(x, scalar)
        else:
            y_arr = arithmetic_op(x_arr, scalar)
            y = arithmetic_op(x, scalar)

            assert all_almost_equal([x, y], [x_arr, y_arr])

        # Right op
        x_arr, x = noise_elements(pspace)

        y_arr = arithmetic_op(scalar, x_arr)
        y = arithmetic_op(scalar, x)

        assert all_almost_equal([x, y], [x_arr, y_arr])

    # Verify that the statement z=op(x, y) gives equivalent results to NumPy
    x_arr, x = noise_elements(space, 1)
    y_arr, y = noise_elements(pspace, 1)

    # non-aliased left
    if arithmetic_op in [operator.iadd,
                         operator.isub,
                         operator.itruediv,
                         operator.imul]:
        # Check for correct error since in-place op is not possible here
        with pytest.raises(TypeError):
            z = arithmetic_op(x, y)
    else:
        z_arr = arithmetic_op(x_arr, y_arr)
        z = arithmetic_op(x, y)

        assert all_almost_equal([x, y, z], [x_arr, y_arr, z_arr])

    # non-aliased right
    z_arr = arithmetic_op(y_arr, x_arr)
    z = arithmetic_op(y, x)

    assert all_almost_equal([x, y, z], [x_arr, y_arr, z_arr])

    # aliased operation
    z_arr = arithmetic_op(y_arr, y_arr)
    z = arithmetic_op(y, y)

    assert all_almost_equal([x, y, z], [x_arr, y_arr, z_arr])
Exemple #35
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def test_primal_dual_l1():
    """Verify that the correct value is returned for l1 dist optimization.

    Solves the optimization problem

        min_x ||x - data_1||_1 + 0.5 ||x - data_2||_1

    which has optimum value data_1.
    """

    # Define the space
    space = odl.rn(5)

    # Operator
    L = [odl.IdentityOperator(space)]

    # Data
    data_1 = odl.util.testutils.noise_element(space)
    data_2 = odl.util.testutils.noise_element(space)

    # Proximals
    f = odl.solvers.L1Norm(space).translated(data_1)
    g = [0.5 * odl.solvers.L1Norm(space).translated(data_2)]

    # Solve with f term dominating
    x = space.zero()
    douglas_rachford_pd(x, f, g, L, tau=3.0, sigma=[1.0], niter=10)

    assert all_almost_equal(x, data_1, places=2)
Exemple #36
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def test_metric():
    H = odl.rn(2)
    v11 = H.element([1, 2])
    v12 = H.element([5, 3])

    v21 = H.element([1, 2])
    v22 = H.element([8, 9])

    # 1-norm
    HxH = odl.ProductSpace(H, H, exponent=1.0)
    w1 = HxH.element([v11, v12])
    w2 = HxH.element([v21, v22])
    assert (HxH.dist(w1,
                     w2) == pytest.approx(H.dist(v11, v21) + H.dist(v12, v22)))

    # 2-norm
    HxH = odl.ProductSpace(H, H, exponent=2.0)
    w1 = HxH.element([v11, v12])
    w2 = HxH.element([v21, v22])
    assert (HxH.dist(w1, w2) == pytest.approx(
        (H.dist(v11, v21)**2 + H.dist(v12, v22)**2)**0.5))

    # inf norm
    HxH = odl.ProductSpace(H, H, exponent=float('inf'))
    w1 = HxH.element([v11, v12])
    w2 = HxH.element([v21, v22])
    assert (HxH.dist(w1, w2) == pytest.approx(
        max(H.dist(v11, v21), H.dist(v12, v22))))
Exemple #37
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def test_functional():
    r3 = odl.rn(3)
    x = r3.element([1, 2, 3])

    op = SumFunctional(r3)

    assert op(x) == 6
Exemple #38
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def test_gradient(space, method, padding):
    """Discretized spatial gradient operator."""

    places = 2 if space.dtype == np.float32 else 4

    with pytest.raises(TypeError):
        Gradient(odl.rn(1), method=method)

    if isinstance(padding, tuple):
        pad_mode, pad_const = padding
    else:
        pad_mode, pad_const = padding, 0

    # DiscreteLp Vector
    dom_vec = noise_element(space)
    dom_vec_arr = dom_vec.asarray()

    # gradient
    grad = Gradient(space,
                    method=method,
                    pad_mode=pad_mode,
                    pad_const=pad_const)
    grad_vec = grad(dom_vec)
    assert len(grad_vec) == space.ndim

    # computation of gradient components with helper function
    for axis, dx in enumerate(space.cell_sides):
        diff = finite_diff(dom_vec_arr,
                           axis=axis,
                           dx=dx,
                           method=method,
                           pad_mode=pad_mode,
                           pad_const=pad_const)

        assert all_almost_equal(grad_vec[axis].asarray(), diff)

    # Test adjoint operator
    derivative = grad.derivative()
    ran_vec = noise_element(derivative.range)
    deriv_grad_vec = derivative(dom_vec)
    adj_grad_vec = derivative.adjoint(ran_vec)
    lhs = ran_vec.inner(deriv_grad_vec)
    rhs = dom_vec.inner(adj_grad_vec)

    # Check not to use trivial data
    assert lhs != 0
    assert rhs != 0
    assert almost_equal(lhs, rhs, places=places)

    # Higher-dimensional arrays
    lin_size = 3
    for ndim in [1, 3, 6]:
        space = odl.uniform_discr([0.] * ndim, [1.] * ndim, [lin_size] * ndim)
        dom_vec = odl.phantom.cuboid(space, [0.2] * ndim, [0.8] * ndim)

        grad = Gradient(space,
                        method=method,
                        pad_mode=pad_mode,
                        pad_const=pad_const)
        grad(dom_vec)
Exemple #39
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def test_nonlinear_functional():
    r3 = odl.rn(3)
    x = r3.element([1, 2, 3])

    op = SumSquaredFunctional(r3)

    assert almost_equal(op(x), np.sum(x ** 2))
Exemple #40
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def test_nearest_interpolation_1d_variants():
    intv = odl.IntervalProd(0, 1)
    part = odl.uniform_partition_fromintv(intv, 5, nodes_on_bdry=False)
    # Coordinate vectors are:
    # [0.1, 0.3, 0.5, 0.7, 0.9]

    space = odl.FunctionSpace(intv)
    dspace = odl.rn(part.size)

    # 'left' variant
    interp_op = NearestInterpolation(space, part, dspace, variant='left')
    function = interp_op([0, 1, 2, 3, 4])

    # Testing two midpoints and the extreme values
    pts = np.array([0.4, 0.8, 0.0, 1.0])
    true_arr = [1, 3, 0, 4]
    assert all_equal(function(pts), true_arr)

    # 'right' variant
    interp_op = NearestInterpolation(space, part, dspace, variant='right')
    function = interp_op([0, 1, 2, 3, 4])

    # Testing two midpoints and the extreme values
    pts = np.array([0.4, 0.8, 0.0, 1.0])
    true_arr = [2, 4, 0, 4]
    assert all_equal(function(pts), true_arr)
Exemple #41
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def test_arithmetic():
    """Test that all standard arithmetic works."""
    space = odl.rn(3)

    # Create elements needed for later
    functional = odl.solvers.L2Norm(space).translated([1, 2, 3])
    functional2 = odl.solvers.L2NormSquared(space)
    operator = odl.IdentityOperator(space) - space.element([4, 5, 6])
    x = noise_element(functional.domain)
    y = noise_element(functional.domain)
    scalar = np.pi

    # Simple tests here, more in depth comes later
    assert functional(x) == functional(x)
    assert functional(x) != functional2(x)
    assert (scalar * functional)(x) == scalar * functional(x)
    assert (scalar * (scalar * functional))(x) == scalar**2 * functional(x)
    assert (functional * scalar)(x) == functional(scalar * x)
    assert ((functional * scalar) * scalar)(x) == functional(scalar**2 * x)
    assert (functional + functional2)(x) == functional(x) + functional2(x)
    assert (functional - functional2)(x) == functional(x) - functional2(x)
    assert (functional * operator)(x) == functional(operator(x))
    assert all_almost_equal((y * functional)(x), y * functional(x))
    assert all_almost_equal((y * (y * functional))(x), (y * y) * functional(x))
    assert all_almost_equal((functional * y)(x), functional(y * x))
    assert all_almost_equal(((functional * y) * y)(x), functional((y * y) * x))
Exemple #42
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    def __init__(self, q):
        assert all(qi.space == q[0].space for qi in q[1:])
        super(KrylovSpaceEmbedding, self).__init__(domain=odl.rn(len(q)),
                                                   range=q[0].space,
                                                   linear=True)

        self.q = q
def test_primal_dual_l1():
    """Verify that the correct value is returned for l1 dist optimization.

    Solves the optimization problem

        min_x ||x - data_1||_1 + 0.5 ||x - data_2||_1

    which has optimum value data_1.
    """

    # Define the space
    space = odl.rn(5)

    # Operator
    L = [odl.IdentityOperator(space)]

    # Data
    data_1 = odl.util.testutils.noise_element(space)
    data_2 = odl.util.testutils.noise_element(space)

    # Proximals
    f = odl.solvers.L1Norm(space).translated(data_1)
    g = [0.5 * odl.solvers.L1Norm(space).translated(data_2)]

    # Solve with f term dominating
    x = space.zero()
    douglas_rachford_pd(x, f, g, L, tau=3.0, sigma=[1.0], niter=10)

    assert all_almost_equal(x, data_1, places=2)
Exemple #44
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def test_discretizedspace_init():
    """Test initialization and basic properties of DiscretizedSpace."""
    # Real space
    part = odl.uniform_partition([0, 0], [1, 1], (2, 4))
    tspace = odl.rn(part.shape)

    discr = DiscretizedSpace(part, tspace)
    assert discr.tspace == tspace
    assert discr.partition == part
    assert discr.exponent == tspace.exponent
    assert discr.axis_labels == ('$x$', '$y$')
    assert discr.is_real

    # Complex space
    tspace_c = odl.cn(part.shape)
    discr = DiscretizedSpace(part, tspace_c)
    assert discr.is_complex

    # Make sure repr shows something
    assert repr(discr) != ''

    # Error scenarios
    part_1d = odl.uniform_partition(0, 1, 2)
    with pytest.raises(ValueError):
        DiscretizedSpace(part_1d, tspace)  # wrong dimensionality

    part_diffshp = odl.uniform_partition([0, 0], [1, 1], (3, 4))
    with pytest.raises(ValueError):
        DiscretizedSpace(part_diffshp, tspace)  # shape mismatch
Exemple #45
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def test_weighted_proximal_L1_norm_close(space):
    """Test for the weighted proximal of the L1 norm near zero"""

    # Set the space.
    space = odl.rn(5)

    # Define the functional on the space.
    func = odl.solvers.L1Norm(space)

    # Set the stepsize.
    sigma = [0.1, 0.2, 0.5, 1.0, 2.0]

    # Set the starting point.
    x = 0.5 * space.one()

    # Calculate the proximal point in-place and out-of-place
    p_ip = space.element()
    func.proximal(sigma)(x, out=p_ip)
    p_oop = func.proximal(sigma)(x)

    # Both should contain the same vector now.
    assert all_almost_equal(p_ip, p_oop)

    # Check if this equals the expected result.
    expected_result = [0.4, 0.3, 0.0, 0.0, 0.0]
    assert all_almost_equal(expected_result, p_ip)
Exemple #46
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def test_matrix_op_call(matrix):
    """Validate result from calls to matrix operators against Numpy."""
    dense_matrix = matrix
    sparse_matrix = scipy.sparse.coo_matrix(dense_matrix)

    # Default 1d case
    dmat_op = MatrixOperator(dense_matrix)
    smat_op = MatrixOperator(sparse_matrix)
    xarr, x = noise_elements(dmat_op.domain)

    true_result = dense_matrix.dot(xarr)
    assert all_almost_equal(dmat_op(x), true_result)
    assert all_almost_equal(smat_op(x), true_result)
    out = dmat_op.range.element()
    dmat_op(x, out=out)
    assert all_almost_equal(out, true_result)
    smat_op(x, out=out)
    assert all_almost_equal(out, true_result)

    # Multi-dimensional case
    domain = odl.rn((2, 2, 4))
    mat_op = MatrixOperator(dense_matrix, domain, axis=2)
    xarr, x = noise_elements(mat_op.domain)
    true_result = np.moveaxis(np.tensordot(dense_matrix, xarr, (1, 2)), 0, 2)
    assert all_almost_equal(mat_op(x), true_result)
    out = mat_op.range.element()
    mat_op(x, out=out)
    assert all_almost_equal(out, true_result)
Exemple #47
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def test_functional_scale():
    r3 = odl.rn(3)

    Aop = SumFunctional(r3)
    x = r3.element([1, 2, 3])
    y = 1

    # Test a range of scalars (scalar multiplication could implement
    # optimizations for (-1, 0, 1).
    scalars = [-1.432, -1, 0, 1, 3.14]
    for scale in scalars:
        C = OperatorRightScalarMult(Aop, scale)

        assert C.is_linear
        assert C.adjoint.is_linear

        assert C(x) == scale * np.sum(x)
        assert all_almost_equal(C.adjoint(y), scale * y * np.ones(3))
        assert all_almost_equal(C.adjoint.adjoint(x), C(x))

        # Using operator overloading
        assert (scale * Aop)(x) == scale * np.sum(x)
        assert (Aop * scale)(x) == scale * np.sum(x)
        assert all_almost_equal((scale * Aop).adjoint(y),
                                scale * y * np.ones(3))
        assert all_almost_equal((Aop * scale).adjoint(y),
                                scale * y * np.ones(3))
Exemple #48
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def test_collocation_interpolation_identity():
    """Check if collocation is left-inverse to interpolation."""
    # Interpolation followed by collocation on the same grid should be
    # the identity
    rect = odl.IntervalProd([0, 0], [1, 1])
    part = odl.uniform_partition_fromintv(rect, [4, 2])
    space = odl.FunctionSpace(rect)
    tspace = odl.rn(part.shape)

    coll_op = PointCollocation(space, part, tspace)
    interp_ops = [
        NearestInterpolation(space, part, tspace, variant='left'),
        NearestInterpolation(space, part, tspace, variant='right'),
        LinearInterpolation(space, part, tspace),
        PerAxisInterpolation(space,
                             part,
                             tspace,
                             schemes=['linear', 'nearest'])
    ]

    values = np.arange(1, 9, dtype='float64').reshape(tspace.shape)

    for interp_op in interp_ops:
        ident_values = coll_op(interp_op(values))
        assert all_almost_equal(ident_values, values)
Exemple #49
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def test_forward_backward_with_lin_ops():
    """Test for the forward-backward solver with linear operatros.

    The test is done by minimizing ||x - b||_2^2 + ||alpha * x||_2^2. The
    general problem is of the form

        ``min_x f(x) + sum_i g_i(L_i x) + h(x)``

    and here we take f = 0, g = ||.||_2^2, L = alpha * IndentityOperator,
    and h = ||. - b||_2^2.
    """

    space = odl.rn(10)
    alpha = 0.1
    b = noise_element(space)

    lin_ops = [alpha * odl.IdentityOperator(space)]
    g = [odl.solvers.L2NormSquared(space)]
    f = odl.solvers.ZeroFunctional(space)

    # Gradient of two-norm square
    h = odl.solvers.L2NormSquared(space).translated(b)

    x = noise_element(space)

    # Explicit solution: x_hat = (I^T * I + (alpha*I)^T * (alpha*I))^-1 * (I*b)
    x_global_min = b / (1 + alpha**2)

    forward_backward_pd(x, f, g, lin_ops, h, tau=0.5, sigma=[1.0], niter=20)

    assert all_almost_equal(x, x_global_min, places=LOW_ACCURACY)
Exemple #50
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def test_nearest_interpolation_2d_float():
    """Test nearest neighbor interpolation in 2d."""
    rect = odl.IntervalProd([0, 0], [1, 1])
    part = odl.uniform_partition_fromintv(rect, [4, 2], nodes_on_bdry=False)
    # Coordinate vectors are:
    # [0.125, 0.375, 0.625, 0.875], [0.25, 0.75]

    fspace = odl.FunctionSpace(rect)
    tspace = odl.rn(part.shape)
    interp_op = NearestInterpolation(fspace, part, tspace)
    function = interp_op(np.reshape([0, 1, 2, 3, 4, 5, 6, 7], part.shape))

    # Evaluate at single point
    val = function([0.3, 0.6])  # closest to index (1, 1) -> 3
    assert val == 3.0
    # Input array, with and without output array
    pts = np.array([[0.3, 0.6], [1.0, 1.0]])
    true_arr = [3, 7]
    assert all_equal(function(pts.T), true_arr)
    out = np.empty(2, dtype='float64')
    function(pts.T, out=out)
    assert all_equal(out, true_arr)
    # Input meshgrid, with and without output array
    mg = sparse_meshgrid([0.3, 1.0], [0.4, 1.0])
    # Indices: (1, 3) x (0, 1)
    true_mg = [[2, 3], [6, 7]]
    assert all_equal(function(mg), true_mg)
    out = np.empty((2, 2), dtype='float64')
    function(mg, out=out)
    assert all_equal(out, true_mg)

    assert repr(interp_op) != ''
Exemple #51
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def _test_getslice(slice):
    # Validate get against python list behaviour
    r6 = odl.rn(6)
    y = [0, 1, 2, 3, 4, 5]
    x = r6.element(y)

    assert all_equal(x[slice].data, y[slice])
Exemple #52
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def test_primal_dual_with_li():
    """Test for the forward-backward solver with infimal convolution.

    The test is done by minimizing the functional ``(g @ l)(x)``, where

        ``(g @ l)(x) = inf_y { g(y) + l(x - y) }``,

    g is the indicator function on [-3, -1], and l(x) = 1/2||x||_2^2.
    The optimal solution to this problem is given by x in [-3, -1].
    """
    # Parameter values for the box constraint
    upper_lim = -1
    lower_lim = -3

    space = odl.rn(1)

    lin_ops = [odl.IdentityOperator(space)]
    g = [odl.solvers.IndicatorBox(space, lower=lower_lim, upper=upper_lim)]
    f = odl.solvers.ZeroFunctional(space)
    l = [odl.solvers.L2NormSquared(space)]

    # Centering around a point further away from [-3,-1].
    x = space.element(10)

    douglas_rachford_pd(x, f, g, lin_ops, tau=0.5, sigma=[1.0], niter=20, l=l)

    assert lower_lim - 10**-LOW_ACCURACY <= float(x)
    assert float(x) <= upper_lim + 10**-LOW_ACCURACY
Exemple #53
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def test_element_1d(exponent):
    discr = odl.uniform_discr(0, 1, 3, impl='numpy', exponent=exponent)
    weight = 1.0 if exponent == float('inf') else discr.cell_volume
    dspace = odl.rn(3, exponent=exponent, weighting=weight)
    elem = discr.element()
    assert isinstance(elem, odl.DiscreteLpElement)
    assert elem.ntuple in dspace
Exemple #54
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def test_operators(arithmetic_op):
    # Test of the operators `+`, `-`, etc work as expected by numpy

    space = odl.rn(3)
    pspace = odl.ProductSpace(space, 2)

    # Interactions with scalars

    for scalar in [-31.2, -1, 0, 1, 2.13]:

        # Left op
        x_arr, x = noise_elements(pspace)
        if scalar == 0 and arithmetic_op in [operator.truediv,
                                             operator.itruediv]:
            # Check for correct zero division behaviour
            with pytest.raises(ZeroDivisionError):
                y = arithmetic_op(x, scalar)
        else:
            y_arr = arithmetic_op(x_arr, scalar)
            y = arithmetic_op(x, scalar)

            assert all_almost_equal([x, y], [x_arr, y_arr])

        # Right op
        x_arr, x = noise_elements(pspace)

        y_arr = arithmetic_op(scalar, x_arr)
        y = arithmetic_op(scalar, x)

        assert all_almost_equal([x, y], [x_arr, y_arr])

    # Verify that the statement z=op(x, y) gives equivalent results to NumPy
    x_arr, x = noise_elements(space, 1)
    y_arr, y = noise_elements(pspace, 1)

    # non-aliased left
    if arithmetic_op in [operator.iadd,
                         operator.isub,
                         operator.itruediv,
                         operator.imul]:
        # Check for correct error since in-place op is not possible here
        with pytest.raises(TypeError):
            z = arithmetic_op(x, y)
    else:
        z_arr = arithmetic_op(x_arr, y_arr)
        z = arithmetic_op(x, y)

        assert all_almost_equal([x, y, z], [x_arr, y_arr, z_arr])

    # non-aliased right
    z_arr = arithmetic_op(y_arr, x_arr)
    z = arithmetic_op(y, x)

    assert all_almost_equal([x, y, z], [x_arr, y_arr, z_arr])

    # aliased operation
    z_arr = arithmetic_op(y_arr, y_arr)
    z = arithmetic_op(y, y)

    assert all_almost_equal([x, y, z], [x_arr, y_arr, z_arr])
Exemple #55
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def test_collocation_interpolation_identity():
    # Check if interpolation followed by collocation on the same grid
    # is the identity
    rect = odl.IntervalProd([0, 0], [1, 1])
    part = odl.uniform_partition_fromintv(rect, [4, 2])
    space = odl.FunctionSpace(rect)
    dspace = odl.rn(part.size)

    coll_op_c = PointCollocation(space, part, dspace, order='C')
    coll_op_f = PointCollocation(space, part, dspace, order='F')
    interp_ops_c = [
        NearestInterpolation(space, part, dspace, variant='left', order='C'),
        NearestInterpolation(space, part, dspace, variant='right', order='C'),
        LinearInterpolation(space, part, dspace, order='C'),
        PerAxisInterpolation(space, part, dspace, order='C',
                             schemes=['linear', 'nearest'])]
    interp_ops_f = [
        NearestInterpolation(space, part, dspace, variant='left', order='F'),
        NearestInterpolation(space, part, dspace, variant='right', order='F'),
        LinearInterpolation(space, part, dspace, order='F'),
        PerAxisInterpolation(space, part, dspace, order='F',
                             schemes=['linear', 'nearest'])]

    values = np.arange(1, 9, dtype='float64')

    for interp_op_c in interp_ops_c:
        ident_values = coll_op_c(interp_op_c(values))
        assert all_almost_equal(ident_values, values)

    for interp_op_f in interp_ops_f:
        ident_values = coll_op_f(interp_op_f(values))
        assert all_almost_equal(ident_values, values)
Exemple #56
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def test_nonlinear_functional():
    r3 = odl.rn(3)
    x = r3.element([1, 2, 3])

    op = SumSquaredFunctional(r3)

    assert op(x) == pytest.approx(np.sum(x ** 2))
def test_nearest_interpolation_2d_float():
    rect = odl.IntervalProd([0, 0], [1, 1])
    part = odl.uniform_partition_fromintv(rect, [4, 2], nodes_on_bdry=False)
    # Coordinate vectors are:
    # [0.125, 0.375, 0.625, 0.875], [0.25, 0.75]

    space = odl.FunctionSpace(rect)
    dspace = odl.rn(part.size)
    interp_op = NearestInterpolation(space, part, dspace)
    function = interp_op([0, 1, 2, 3, 4, 5, 6, 7])

    # Evaluate at single point
    val = function([0.3, 0.6])  # closest to index (1, 1) -> 3
    assert val == 3.0
    # Input array, with and without output array
    pts = np.array([[0.3, 0.6],
                    [1.0, 1.0]])
    true_arr = [3, 7]
    assert all_equal(function(pts.T), true_arr)
    out = np.empty(2, dtype='float64')
    function(pts.T, out=out)
    assert all_equal(out, true_arr)
    # Input meshgrid, with and without output array
    mg = sparse_meshgrid([0.3, 1.0], [0.4, 1.0])
    # Indices: (1, 3) x (0, 1)
    true_mg = [[2, 3],
               [6, 7]]
    assert all_equal(function(mg), true_mg)
    out = np.empty((2, 2), dtype='float64')
    function(mg, out=out)
    assert all_equal(out, true_mg)
Exemple #58
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def test_primal_dual_no_operator():
    """Verify that the correct value is returned when there is no operator.

    Solves the optimization problem

        min_x ||x - data_1||_1

    which has optimum value data_1.
    """

    # Define the space
    space = odl.rn(5)

    # Operator
    L = []

    # Data
    data_1 = odl.util.testutils.noise_element(space)

    # Proximals
    f = odl.solvers.L1Norm(space).translated(data_1)
    g = []

    # Solve with f term dominating
    x = space.zero()
    douglas_rachford_pd(x, f, g, L, tau=3.0, sigma=[], niter=10)

    assert all_almost_equal(x, data_1, ndigits=2)