Beispiel #1
0
class TestVisualization(geomstats.tests.TestCase):
    def setUp(self):
        self.n_samples = 10
        self.SO3_GROUP = SpecialOrthogonal(n=3, point_type='vector')
        self.SE3_GROUP = SpecialEuclidean(n=3, point_type='vector')
        self.S1 = Hypersphere(dim=1)
        self.S2 = Hypersphere(dim=2)
        self.H2 = Hyperbolic(dim=2)
        self.H2_half_plane = PoincareHalfSpace(dim=2)

        plt.figure()

    @staticmethod
    def test_tutorial_matplotlib():
        visualization.tutorial_matplotlib()

    def test_plot_points_so3(self):
        points = self.SO3_GROUP.random_uniform(self.n_samples)
        visualization.plot(points, space='SO3_GROUP')

    def test_plot_points_se3(self):
        points = self.SE3_GROUP.random_uniform(self.n_samples)
        visualization.plot(points, space='SE3_GROUP')

    @geomstats.tests.np_and_pytorch_only
    def test_plot_points_s1(self):
        points = self.S1.random_uniform(self.n_samples)
        visualization.plot(points, space='S1')

    def test_plot_points_s2(self):
        points = self.S2.random_uniform(self.n_samples)
        visualization.plot(points, space='S2')

    def test_plot_points_h2_poincare_disk(self):
        points = self.H2.random_uniform(self.n_samples)
        visualization.plot(points, space='H2_poincare_disk')

    def test_plot_points_h2_poincare_half_plane_ext(self):
        points = self.H2.random_uniform(self.n_samples)
        visualization.plot(points,
                           space='H2_poincare_half_plane',
                           point_type='extrinsic')

    def test_plot_points_h2_poincare_half_plane_none(self):
        points = self.H2_half_plane.random_uniform(self.n_samples)
        visualization.plot(points, space='H2_poincare_half_plane')

    def test_plot_points_h2_poincare_half_plane_hs(self):
        points = self.H2_half_plane.random_uniform(self.n_samples)
        visualization.plot(points,
                           space='H2_poincare_half_plane',
                           point_type='half_space')

    def test_plot_points_h2_klein_disk(self):
        points = self.H2.random_uniform(self.n_samples)
        visualization.plot(points, space='H2_klein_disk')
Beispiel #2
0
class TestVisualizationMethods(geomstats.tests.TestCase):
    def setUp(self):
        self.n_samples = 10
        self.SO3_GROUP = SpecialOrthogonal(n=3)
        self.SE3_GROUP = SpecialEuclidean(n=3)
        self.S1 = Hypersphere(dim=1)
        self.S2 = Hypersphere(dim=2)
        self.H2 = Hyperbolic(dim=2)

        plt.figure()

    @geomstats.tests.np_only
    def test_plot_points_so3(self):
        points = self.SO3_GROUP.random_uniform(self.n_samples)
        visualization.plot(points, space='SO3_GROUP')

    @geomstats.tests.np_only
    def test_plot_points_se3(self):
        points = self.SE3_GROUP.random_uniform(self.n_samples)
        visualization.plot(points, space='SE3_GROUP')

    @geomstats.tests.np_only
    def test_plot_points_s1(self):
        points = self.S1.random_uniform(self.n_samples)
        visualization.plot(points, space='S1')

    @geomstats.tests.np_only
    def test_plot_points_s2(self):
        points = self.S2.random_uniform(self.n_samples)
        visualization.plot(points, space='S2')

    @geomstats.tests.np_only
    def test_plot_points_h2_poincare_disk(self):
        points = self.H2.random_uniform(self.n_samples)
        visualization.plot(points, space='H2_poincare_disk')

    @geomstats.tests.np_only
    def test_plot_points_h2_poincare_half_plane(self):
        points = self.H2.random_uniform(self.n_samples)
        visualization.plot(points, space='H2_poincare_half_plane')

    @geomstats.tests.np_only
    def test_plot_points_h2_klein_disk(self):
        points = self.H2.random_uniform(self.n_samples)
        visualization.plot(points, space='H2_klein_disk')
Beispiel #3
0
def main():
    """Perform tangent PCA at the mean."""
    fig = plt.figure(figsize=(15, 5))

    hyperbolic_plane = Hyperbolic(dimension=2)

    data = hyperbolic_plane.random_uniform(n_samples=140)
    mean = hyperbolic_plane.metric.mean(data)

    tpca = TangentPCA(metric=hyperbolic_plane.metric, n_components=2)
    tpca = tpca.fit(data, base_point=mean)
    tangent_projected_data = tpca.transform(data)

    geodesic_0 = hyperbolic_plane.metric.geodesic(
        initial_point=mean, initial_tangent_vec=tpca.components_[0])
    geodesic_1 = hyperbolic_plane.metric.geodesic(
        initial_point=mean, initial_tangent_vec=tpca.components_[1])

    n_steps = 100
    t = np.linspace(-1, 1, n_steps)
    geodesic_points_0 = geodesic_0(t)
    geodesic_points_1 = geodesic_1(t)

    print('Coordinates of the Log of the first 5 data points at the mean, '
          'projected on the principal components:')
    print(tangent_projected_data[:5])

    ax_var = fig.add_subplot(121)
    xticks = np.arange(1, 2 + 1, 1)
    ax_var.xaxis.set_ticks(xticks)
    ax_var.set_title('Explained variance')
    ax_var.set_xlabel('Number of Principal Components')
    ax_var.set_ylim((0, 1))
    ax_var.plot(xticks, tpca.explained_variance_ratio_)

    ax = fig.add_subplot(122)

    visualization.plot(mean,
                       ax,
                       space='H2_poincare_disk',
                       color='darkgreen',
                       s=10)
    visualization.plot(geodesic_points_0,
                       ax,
                       space='H2_poincare_disk',
                       linewidth=2)
    visualization.plot(geodesic_points_1,
                       ax,
                       space='H2_poincare_disk',
                       linewidth=2)
    visualization.plot(data,
                       ax,
                       space='H2_poincare_disk',
                       color='black',
                       alpha=0.7)

    plt.show()
Beispiel #4
0
class TestFrechetMean(geomstats.tests.TestCase):
    _multiprocess_can_split_ = True

    def setUp(self):
        self.sphere = Hypersphere(dimension=4)
        self.hyperbolic = Hyperbolic(dimension=3)
        self.euclidean = Euclidean(dimension=2)
        self.minkowski = Minkowski(dimension=2)

    @geomstats.tests.np_only
    def test_adaptive_gradient_descent_sphere(self):
        n_tests = 100
        result = gs.zeros(n_tests)
        expected = gs.zeros(n_tests)

        for i in range(n_tests):
            # take 2 random points, compute their mean, and verify that
            # log of each at the mean is opposite
            points = self.sphere.random_uniform(n_samples=2)
            mean = _adaptive_gradient_descent(points=points,
                                              metric=self.sphere.metric)

            logs = self.sphere.metric.log(point=points, base_point=mean)
            result[i] = gs.linalg.norm(logs[1, :] + logs[0, :])

        self.assertAllClose(expected, result, rtol=1e-10, atol=1e-10)

    @geomstats.tests.np_and_pytorch_only
    def test_estimate_and_belongs_sphere(self):
        point_a = gs.array([1., 0., 0., 0., 0.])
        point_b = gs.array([0., 1., 0., 0., 0.])
        points = gs.zeros((2, point_a.shape[0]))
        points[0, :] = point_a
        points[1, :] = point_b

        mean = FrechetMean(metric=self.sphere.metric)
        mean.fit(points)

        result = self.sphere.belongs(mean.estimate_)
        expected = gs.array([[True]])
        self.assertAllClose(result, expected)

    @geomstats.tests.np_and_pytorch_only
    def test_variance_sphere(self):
        point = gs.array([0., 0., 0., 0., 1.])
        points = gs.zeros((2, point.shape[0]))
        points[0, :] = point
        points[1, :] = point

        result = variance(points, base_point=point, metric=self.sphere.metric)
        expected = helper.to_scalar(0.)

        self.assertAllClose(expected, result)

    @geomstats.tests.np_and_pytorch_only
    def test_estimate_sphere(self):
        point = gs.array([0., 0., 0., 0., 1.])
        points = gs.zeros((2, point.shape[0]))
        points[0, :] = point
        points[1, :] = point

        mean = FrechetMean(metric=self.sphere.metric)
        mean.fit(X=points)

        result = mean.estimate_
        expected = helper.to_vector(point)

        self.assertAllClose(expected, result)

    @geomstats.tests.np_and_tf_only
    def test_variance_hyperbolic(self):
        point = gs.array([2., 1., 1., 1.])
        points = gs.array([point, point])
        result = variance(points,
                          base_point=point,
                          metric=self.hyperbolic.metric)
        expected = helper.to_scalar(0.)

        self.assertAllClose(result, expected)

    @geomstats.tests.np_and_tf_only
    def test_estimate_hyperbolic(self):
        point = gs.array([2., 1., 1., 1.])
        points = gs.array([point, point])

        mean = FrechetMean(metric=self.hyperbolic.metric)
        mean.fit(X=points)

        result = mean.estimate_
        expected = helper.to_vector(point)

        self.assertAllClose(result, expected)

    @geomstats.tests.np_and_tf_only
    def test_estimate_and_belongs_hyperbolic(self):
        point_a = self.hyperbolic.random_uniform()
        point_b = self.hyperbolic.random_uniform()
        point_c = self.hyperbolic.random_uniform()
        points = gs.concatenate([point_a, point_b, point_c], axis=0)

        mean = FrechetMean(metric=self.hyperbolic.metric)
        mean.fit(X=points)

        result = self.hyperbolic.belongs(mean.estimate_)
        expected = gs.array([[True]])

        self.assertAllClose(result, expected)

    def test_mean_euclidean(self):
        point = gs.array([[1., 4.]])

        mean = FrechetMean(metric=self.euclidean.metric)
        points = [point, point, point]
        mean.fit(points)

        result = mean.estimate_
        expected = point
        expected = helper.to_vector(expected)

        self.assertAllClose(result, expected)

        points = gs.array([[1., 2.], [2., 3.], [3., 4.], [4., 5.]])
        weights = gs.array([1., 2., 1., 2.])

        mean = FrechetMean(metric=self.euclidean.metric)
        mean.fit(points, weights=weights)

        result = mean.estimate_
        expected = gs.array([16. / 6., 22. / 6.])
        expected = helper.to_vector(expected)

        self.assertAllClose(result, expected)

    def test_variance_euclidean(self):
        points = gs.array([[1., 2.], [2., 3.], [3., 4.], [4., 5.]])
        weights = gs.array([1., 2., 1., 2.])
        base_point = gs.zeros(2)
        result = variance(points,
                          weights=weights,
                          base_point=base_point,
                          metric=self.euclidean.metric)
        # we expect the average of the points' sq norms.
        expected = (1 * 5. + 2 * 13. + 1 * 25. + 2 * 41.) / 6.
        expected = helper.to_scalar(expected)

        self.assertAllClose(result, expected)

    def test_mean_minkowski(self):
        point = gs.array([[2., -math.sqrt(3)]])
        points = [point, point, point]

        mean = FrechetMean(metric=self.minkowski.metric)
        mean.fit(points)
        result = mean.estimate_

        expected = point
        expected = helper.to_vector(expected)

        self.assertAllClose(result, expected)

        points = gs.array([[1., 0.], [2., math.sqrt(3)], [3., math.sqrt(8)],
                           [4., math.sqrt(24)]])
        weights = gs.array([1., 2., 1., 2.])

        mean = FrechetMean(metric=self.minkowski.metric)
        mean.fit(points, weights=weights)
        result = mean.estimate_
        result = self.minkowski.belongs(result)
        expected = gs.array([[True]])

        self.assertAllClose(result, expected)

    def test_variance_minkowski(self):
        points = gs.array([[1., 0.], [2., math.sqrt(3)], [3., math.sqrt(8)],
                           [4., math.sqrt(24)]])
        weights = gs.array([1., 2., 1., 2.])
        base_point = gs.array([-1., 0.])
        var = variance(points,
                       weights=weights,
                       base_point=base_point,
                       metric=self.minkowski.metric)
        result = helper.to_scalar(var != 0)
        # we expect the average of the points' Minkowski sq norms.
        expected = helper.to_scalar(gs.array([True]))
        self.assertAllClose(result, expected)
class TestHyperbolicMethods(geomstats.tests.TestCase):
    def setUp(self):
        gs.random.seed(1234)
        self.dimension = 3
        self.space = Hyperbolic(dimension=self.dimension)
        self.metric = self.space.metric
        self.n_samples = 10

    def test_random_uniform_and_belongs(self):
        point = self.space.random_uniform()
        result = self.space.belongs(point)
        expected = gs.array([[True]])

        self.assertAllClose(result, expected)

    def test_random_uniform(self):
        result = self.space.random_uniform()

        self.assertAllClose(gs.shape(result), (1, self.dimension + 1))

    def test_intrinsic_and_extrinsic_coords(self):
        """
        Test that the composition of
        intrinsic_to_extrinsic_coords and
        extrinsic_to_intrinsic_coords
        gives the identity.
        """
        point_int = gs.ones(self.dimension)
        point_ext = self.space.intrinsic_to_extrinsic_coords(point_int)
        result = self.space.extrinsic_to_intrinsic_coords(point_ext)
        expected = point_int
        expected = helper.to_vector(expected)
        self.assertAllClose(result, expected)

        point_ext = gs.array([2.0, 1.0, 1.0, 1.0])
        point_int = self.space.extrinsic_to_intrinsic_coords(point_ext)
        result = self.space.intrinsic_to_extrinsic_coords(point_int)
        expected = point_ext
        expected = helper.to_vector(expected)

        self.assertAllClose(result, expected)

    def test_intrinsic_and_extrinsic_coords_vectorization(self):
        """
        Test that the composition of
        intrinsic_to_extrinsic_coords and
        extrinsic_to_intrinsic_coords
        gives the identity.
        """
        point_int = gs.array([[.1, 0., 0., .1, 0., 0.],
                              [.1, .1, .1, .4, .1, 0.],
                              [.1, .3, 0., .1, 0., 0.],
                              [-0.1, .1, -.4, .1, -.01, 0.],
                              [0., 0., .1, .1, -0.08, -0.1],
                              [.1, .1, .1, .1, 0., -0.5]])
        point_ext = self.space.intrinsic_to_extrinsic_coords(point_int)
        result = self.space.extrinsic_to_intrinsic_coords(point_ext)
        expected = point_int
        expected = helper.to_vector(expected)

        self.assertAllClose(result, expected)

        point_ext = gs.array([[2., 1., 1., 1.],
                              [4., 1., 3., math.sqrt(5.)],
                              [3., 2., 0., 2.]])
        point_int = self.space.extrinsic_to_intrinsic_coords(point_ext)
        result = self.space.intrinsic_to_extrinsic_coords(point_int)
        expected = point_ext
        expected = helper.to_vector(expected)

        self.assertAllClose(result, expected)

    def test_log_and_exp_general_case(self):
        """
        Test that the riemannian exponential
        and the riemannian logarithm are inverse.

        Expect their composition to give the identity function.
        """
        # Riemannian Log then Riemannian Exp
        # General case
        base_point = gs.array([4.0, 1., 3.0, math.sqrt(5.)])
        point = gs.array([2.0, 1.0, 1.0, 1.0])

        log = self.metric.log(point=point, base_point=base_point)

        result = self.metric.exp(tangent_vec=log, base_point=base_point)
        expected = helper.to_vector(point)
        self.assertAllClose(result, expected)

    def test_exp_and_belongs(self):
        H2 = Hyperbolic(dimension=2)
        METRIC = H2.metric

        base_point = gs.array([1., 0., 0.])
        with self.session():
            self.assertTrue(gs.eval(H2.belongs(base_point)))

        tangent_vec = H2.projection_to_tangent_space(
            vector=gs.array([1., 2., 1.]),
            base_point=base_point)
        exp = METRIC.exp(tangent_vec=tangent_vec,
                         base_point=base_point)
        with self.session():
            self.assertTrue(gs.eval(H2.belongs(exp)))

    @geomstats.tests.np_and_pytorch_only
    def test_exp_vectorization(self):
        n_samples = 3
        dim = self.dimension + 1

        one_vec = gs.array([2.0, 1.0, 1.0, 1.0])
        one_base_point = gs.array([4.0, 3., 1.0, math.sqrt(5)])
        n_vecs = gs.array([[2., 1., 1., 1.],
                           [4., 1., 3., math.sqrt(5.)],
                           [3., 2., 0., 2.]])
        n_base_points = gs.array([
            [2.0, 0.0, 1.0, math.sqrt(2)],
            [5.0, math.sqrt(8), math.sqrt(8), math.sqrt(8)],
            [1.0, 0.0, 0.0, 0.0]])

        one_tangent_vec = self.space.projection_to_tangent_space(
            one_vec, base_point=one_base_point)
        result = self.metric.exp(one_tangent_vec, one_base_point)
        self.assertAllClose(gs.shape(result), (1, dim))

        n_tangent_vecs = self.space.projection_to_tangent_space(
            n_vecs, base_point=one_base_point)
        result = self.metric.exp(n_tangent_vecs, one_base_point)
        self.assertAllClose(gs.shape(result), (n_samples, dim))

        expected = gs.zeros((n_samples, dim))

        with self.session():
            for i in range(n_samples):
                expected[i] = gs.eval(
                    self.metric.exp(n_tangent_vecs[i], one_base_point))
            expected = helper.to_vector(gs.array(expected))
            self.assertAllClose(result, expected)

        one_tangent_vec = self.space.projection_to_tangent_space(
            one_vec, base_point=n_base_points)
        result = self.metric.exp(one_tangent_vec, n_base_points)
        self.assertAllClose(gs.shape(result), (n_samples, dim))

        expected = gs.zeros((n_samples, dim))
        with self.session():
            for i in range(n_samples):
                expected[i] = gs.eval(self.metric.exp(one_tangent_vec[i],
                                      n_base_points[i]))
            expected = helper.to_vector(gs.array(expected))
            self.assertAllClose(result, expected)

        n_tangent_vecs = self.space.projection_to_tangent_space(
            n_vecs, base_point=n_base_points)
        result = self.metric.exp(n_tangent_vecs, n_base_points)
        self.assertAllClose(gs.shape(result), (n_samples, dim))

        expected = gs.zeros((n_samples, dim))
        with self.session():
            for i in range(n_samples):
                expected[i] = gs.eval(self.metric.exp(n_tangent_vecs[i],
                                      n_base_points[i]))
            expected = helper.to_vector(gs.array(expected))
            self.assertAllClose(result, expected)

    def test_log_vectorization(self):
        n_samples = 3
        dim = self.dimension + 1

        one_point = gs.array([2.0, 1.0, 1.0, 1.0])
        one_base_point = gs.array([4.0, 3., 1.0, math.sqrt(5)])
        n_points = gs.array([[2.0, 1.0, 1.0, 1.0],
                             [4.0, 1., 3.0, math.sqrt(5)],
                             [3.0, 2.0, 0.0, 2.0]])
        n_base_points = gs.array([
            [2.0, 0.0, 1.0, math.sqrt(2)],
            [5.0, math.sqrt(8), math.sqrt(8), math.sqrt(8)],
            [1.0, 0.0, 0.0, 0.0]])

        result = self.metric.log(one_point, one_base_point)
        self.assertAllClose(gs.shape(result), (1, dim))

        result = self.metric.log(n_points, one_base_point)
        self.assertAllClose(gs.shape(result), (n_samples, dim))

        result = self.metric.log(one_point, n_base_points)
        self.assertAllClose(gs.shape(result), (n_samples, dim))

        result = self.metric.log(n_points, n_base_points)
        self.assertAllClose(gs.shape(result), (n_samples, dim))

    def test_inner_product(self):
        """
        Test that the inner product between two tangent vectors
        is the Minkowski inner product.
        """
        minkowski_space = Minkowski(self.dimension + 1)
        base_point = gs.array(
            [1.16563816, 0.36381045, -0.47000603, 0.07381469])

        tangent_vec_a = self.space.projection_to_tangent_space(
            vector=gs.array([10., 200., 1., 1.]),
            base_point=base_point)

        tangent_vec_b = self.space.projection_to_tangent_space(
            vector=gs.array([11., 20., -21., 0.]),
            base_point=base_point)

        result = self.metric.inner_product(
            tangent_vec_a, tangent_vec_b, base_point)

        expected = minkowski_space.metric.inner_product(
            tangent_vec_a, tangent_vec_b, base_point)

        with self.session():
            self.assertAllClose(result, expected)

    def test_squared_norm_and_squared_dist(self):
        """
        Test that the squared distance between two points is
        the squared norm of their logarithm.
        """
        point_a = gs.array([2.0, 1.0, 1.0, 1.0])
        point_b = gs.array([4.0, 1., 3.0, math.sqrt(5)])
        log = self.metric.log(point=point_a, base_point=point_b)
        result = self.metric.squared_norm(vector=log)
        expected = self.metric.squared_dist(point_a, point_b)

        with self.session():
            self.assertAllClose(result, expected)

    def test_norm_and_dist(self):
        """
        Test that the distance between two points is
        the norm of their logarithm.
        """
        point_a = gs.array([2.0, 1.0, 1.0, 1.0])
        point_b = gs.array([4.0, 1., 3.0, math.sqrt(5)])
        log = self.metric.log(point=point_a, base_point=point_b)
        result = self.metric.norm(vector=log)
        expected = self.metric.dist(point_a, point_b)

        with self.session():
            self.assertAllClose(result, expected)

    def test_log_and_exp_edge_case(self):
        """
        Test that the riemannian exponential
        and the riemannian logarithm are inverse.

        Expect their composition to give the identity function.
        """
        # Riemannian Log then Riemannian Exp
        # Edge case: two very close points, base_point_2 and point_2,
        # form an angle < epsilon
        base_point_intrinsic = gs.array([1., 2., 3.])
        base_point = self.space.intrinsic_to_extrinsic_coords(
            base_point_intrinsic)
        point_intrinsic = (base_point_intrinsic +
                           1e-12 * gs.array([-1., -2., 1.]))
        point = self.space.intrinsic_to_extrinsic_coords(
            point_intrinsic)

        log = self.metric.log(point=point, base_point=base_point)
        result = self.metric.exp(tangent_vec=log, base_point=base_point)
        expected = point

        with self.session():
            self.assertAllClose(result, expected)

    @geomstats.tests.np_and_tf_only
    def test_exp_and_log_and_projection_to_tangent_space_general_case(self):
        """
        Test that the riemannian exponential
        and the riemannian logarithm are inverse.

        Expect their composition to give the identity function.
        """
        # Riemannian Exp then Riemannian Log
        # General case
        base_point = gs.array([4.0, 1., 3.0, math.sqrt(5)])
        vector = gs.array([2.0, 1.0, 1.0, 1.0])
        vector = self.space.projection_to_tangent_space(
            vector=vector,
            base_point=base_point)
        exp = self.metric.exp(tangent_vec=vector, base_point=base_point)
        result = self.metric.log(point=exp, base_point=base_point)

        expected = vector
        with self.session():
            self.assertAllClose(result, expected)

    def test_dist(self):
        # Distance between a point and itself is 0.
        point_a = gs.array([4.0, 1., 3.0, math.sqrt(5)])
        point_b = point_a
        result = self.metric.dist(point_a, point_b)
        expected = gs.array([[0]])

        with self.session():
            self.assertAllClose(result, expected)

    @geomstats.tests.np_and_pytorch_only
    def test_dist_poincare(self):

        point_a = gs.array([0.5, 0.5])
        point_b = gs.array([0.5, -0.5])

        self.space.metric.point_type = 'ball'

        dist_a_b = self.metric.dist(point_a, point_b)
        self.space.metric.point_type = 'extrinsic'

        result = dist_a_b
        expected = gs.array([[2.887270927429199]])

        with self.session():
            self.assertAllClose(result, expected)

    def test_exp_poincare(self):

        self.space.metric.point_type = 'ball'
        result = 0
        expected = 0
        self.space.metric.point_type = 'extrinsic'
        with self.session():
            self.assertAllClose(result, expected)

    @geomstats.tests.np_only
    def test_log_poincare(self):

        point = gs.array([0.3, 0.5])
        base_point = gs.array([0.3, 0.3])

        self.space.metric.point_type = 'ball'
        result = self.space.metric.log(point, base_point)
        expected = gs.array([-0.01733576, 0.21958634])

        self.space.metric.point_type = 'extrinsic'
        with self.session():
            self.assertAllClose(result, expected)

    def test_exp_and_dist_and_projection_to_tangent_space(self):
        base_point = gs.array([4.0, 1., 3.0, math.sqrt(5)])
        vector = gs.array([0.001, 0., -.00001, -.00003])
        tangent_vec = self.space.projection_to_tangent_space(
            vector=vector,
            base_point=base_point)
        exp = self.metric.exp(tangent_vec=tangent_vec,
                              base_point=base_point)

        result = self.metric.dist(base_point, exp)
        sq_norm = self.metric.embedding_metric.squared_norm(
            tangent_vec)
        expected = sq_norm
        with self.session():
            self.assertAllClose(result, expected, atol=1e-2)

    def test_geodesic_and_belongs(self):
        # TODO(nina): Fix this tests, as it fails when geodesic goes "too far"
        initial_point = gs.array([4.0, 1., 3.0, math.sqrt(5)])
        n_geodesic_points = 100
        vector = gs.array([1., 0., 0., 0.])

        initial_tangent_vec = self.space.projection_to_tangent_space(
            vector=vector,
            base_point=initial_point)
        geodesic = self.metric.geodesic(
            initial_point=initial_point,
            initial_tangent_vec=initial_tangent_vec)

        t = gs.linspace(start=0., stop=1., num=n_geodesic_points)
        points = geodesic(t)

        result = self.space.belongs(points)
        expected = gs.array(n_geodesic_points * [[True]])

        with self.session():
            self.assertAllClose(expected, result)

    def test_exp_and_log_and_projection_to_tangent_space_edge_case(self):
        """
        Test that the riemannian exponential and
        the riemannian logarithm are inverse.

        Expect their composition to give the identity function.
        """
        # Riemannian Exp then Riemannian Log
        # Edge case: tangent vector has norm < epsilon
        base_point = gs.array([2., 1., 1., 1.])
        vector = 1e-10 * gs.array([.06, -51., 6., 5.])

        exp = self.metric.exp(tangent_vec=vector, base_point=base_point)
        result = self.metric.log(point=exp, base_point=base_point)
        expected = self.space.projection_to_tangent_space(
            vector=vector,
            base_point=base_point)

        self.assertAllClose(result, expected, atol=1e-8)

    @geomstats.tests.np_and_tf_only
    def test_variance(self):
        point = gs.array([2., 1., 1., 1.])
        points = gs.array([point, point])
        result = self.metric.variance(points)
        expected = helper.to_scalar(0.)

        self.assertAllClose(result, expected)

    @geomstats.tests.np_and_tf_only
    def test_mean(self):
        point = gs.array([2., 1., 1., 1.])
        points = gs.array([point, point])
        result = self.metric.mean(points)
        expected = helper.to_vector(point)

        self.assertAllClose(result, expected)

    @geomstats.tests.np_and_tf_only
    def test_mean_and_belongs(self):
        point_a = self.space.random_uniform()
        point_b = self.space.random_uniform()
        point_c = self.space.random_uniform()
        points = gs.concatenate([point_a, point_b, point_c], axis=0)

        mean = self.metric.mean(points)
        result = self.space.belongs(mean)
        expected = gs.array([[True]])

        self.assertAllClose(result, expected)

    @geomstats.tests.np_only
    def test_scaled_inner_product(self):
        base_point_intrinsic = gs.array([1, 1, 1])
        base_point = self.space.intrinsic_to_extrinsic_coords(
            base_point_intrinsic)
        tangent_vec_a = gs.array([1, 2, 3, 4])
        tangent_vec_b = gs.array([5, 6, 7, 8])
        tangent_vec_a = self.space.projection_to_tangent_space(
            tangent_vec_a,
            base_point)
        tangent_vec_b = self.space.projection_to_tangent_space(
            tangent_vec_b,
            base_point)
        scale = 2
        default_space = Hyperbolic(dimension=self.dimension)
        scaled_space = Hyperbolic(dimension=self.dimension, scale=2)
        inner_product_default_metric = \
            default_space.metric.inner_product(
                tangent_vec_a,
                tangent_vec_b,
                base_point)
        inner_product_scaled_metric = \
            scaled_space.metric.inner_product(
                tangent_vec_a,
                tangent_vec_b,
                base_point)
        result = inner_product_scaled_metric
        expected = scale ** 2 * inner_product_default_metric
        self.assertAllClose(result, expected)

    @geomstats.tests.np_only
    def test_scaled_squared_norm(self):
        base_point_intrinsic = gs.array([1, 1, 1])
        base_point = self.space.intrinsic_to_extrinsic_coords(
            base_point_intrinsic)
        tangent_vec = gs.array([1, 2, 3, 4])
        tangent_vec = self.space.projection_to_tangent_space(
            tangent_vec, base_point)
        scale = 2
        default_space = Hyperbolic(dimension=self.dimension)
        scaled_space = Hyperbolic(dimension=self.dimension, scale=2)
        squared_norm_default_metric = default_space.metric.squared_norm(
            tangent_vec, base_point)
        squared_norm_scaled_metric = scaled_space.metric.squared_norm(
            tangent_vec, base_point)
        result = squared_norm_scaled_metric
        expected = scale ** 2 * squared_norm_default_metric
        self.assertAllClose(result, expected)

    @geomstats.tests.np_only
    def test_scaled_distance(self):
        point_a_intrinsic = gs.array([1, 2, 3])
        point_b_intrinsic = gs.array([4, 5, 6])
        point_a = self.space.intrinsic_to_extrinsic_coords(point_a_intrinsic)
        point_b = self.space.intrinsic_to_extrinsic_coords(point_b_intrinsic)
        scale = 2
        default_space = Hyperbolic(dimension=self.dimension)
        scaled_space = Hyperbolic(dimension=self.dimension, scale=2)
        distance_default_metric = default_space.metric.dist(point_a, point_b)
        distance_scaled_metric = scaled_space.metric.dist(point_a, point_b)
        result = distance_scaled_metric
        expected = scale * distance_default_metric
        self.assertAllClose(result, expected)