def test_discrete_barycenter_grid(self, lse_mode, debiased, epsilon):
"""Tests the discrete barycenters on a 5x5x5 grid.
Puts two masses on opposing ends of the hypercube with small noise in
between. Check that their W barycenter sits (mostly) at the middle of the
hypercube (e.g. index (5x5x5-1)/2)
Args:
lse_mode: bool, lse or scaling computations.
debiased: bool, use (or not) debiasing as proposed in
https://arxiv.org/abs/2006.02575
epsilon: float, regularization parameter
"""
size = jnp.array([5, 5, 5])
grid_3d = grid.Grid(grid_size=size, epsilon=epsilon)
a = jnp.ones(size)
b = jnp.ones(size)
a = a.ravel()
b = b.ravel()
a = jax.ops.index_update(a, 0, 10000)
b = jax.ops.index_update(b, -1, 10000)
a = a / jnp.sum(a)
b = b / jnp.sum(b)
threshold = 1e-2
_, _, bar, errors = db.discrete_barycenter(grid_3d,
a=jnp.stack((a, b)),
threshold=threshold,
lse_mode=lse_mode,
debiased=debiased)
self.assertGreater(bar[(jnp.prod(size) - 1) // 2], 0.7)
self.assertGreater(1, bar[(jnp.prod(size) - 1) // 2])
err = errors[jnp.isfinite(errors)][-1]
self.assertGreater(threshold, err)
def reg_ot(x):
geom = grid.Grid(x=x, epsilon=1.0)
return sinkhorn.sinkhorn(geom,
a=a,
b=b,
threshold=0.1,
lse_mode=lse_mode).reg_ot_cost
def test_autograd_sinkhorn_x_grid(self, lse_mode):
"""Test gradient w.r.t. probability weights."""
eps = 1e-4 # perturbation magnitude
keys = jax.random.split(self.rng, 3)
x = (jnp.array([.0, 1.0], dtype=jnp.float32),
jnp.array([.3, .4, .7], dtype=jnp.float32),
jnp.array([1.0, 1.3, 2.4, 3.7], dtype=jnp.float32))
grid_size = tuple([xs.shape[0] for xs in x])
a = jax.random.uniform(keys[0], grid_size) + 1
b = jax.random.uniform(keys[1], grid_size) + 1
a = a.ravel() / jnp.sum(a)
b = b.ravel() / jnp.sum(b)
geom = grid.Grid(x=x, epsilon=1)
def reg_ot(a, b):
return sinkhorn.sinkhorn(geom,
a=a,
b=b,
threshold=0.001,
lse_mode=lse_mode).reg_ot_cost
reg_ot_and_grad = jax.jit(jax.value_and_grad(reg_ot))
_, grad_reg_ot = reg_ot_and_grad(a, b)
delta = jax.random.uniform(keys[2], grid_size).ravel()
delta = delta - jnp.mean(delta)
# center perturbation
reg_ot_delta_plus = reg_ot(a + eps * delta, b)
reg_ot_delta_minus = reg_ot(a - eps * delta, b)
delta_dot_grad = jnp.sum(delta * grad_reg_ot)
self.assertAllClose(delta_dot_grad,
(reg_ot_delta_plus - reg_ot_delta_minus) /
(2 * eps),
rtol=1e-03,
atol=1e-02)
def test_autograd_sinkhorn_grid(self, lse_mode):
"""Test gradient w.r.t. probability weights."""
eps = 1e-3 # perturbation magnitude
keys = jax.random.split(self.rng, 3)
grid_size = (2, 3, 4)
a = jax.random.uniform(keys[0], grid_size) + 1.0
b = jax.random.uniform(keys[1], grid_size) + 1.0
a = a.ravel() / jnp.sum(a)
b = b.ravel() / jnp.sum(b)
geom = grid.Grid(grid_size=grid_size, epsilon=0.2)
def reg_ot(a, b):
return sinkhorn.sinkhorn(
geom, a=a, b=b, threshold=0.1, lse_mode=lse_mode,
implicit_differentiation=False).reg_ot_cost
reg_ot_and_grad = jax.jit(jax.value_and_grad(reg_ot))
_, grad_reg_ot = reg_ot_and_grad(a, b)
delta = jax.random.uniform(keys[2], grid_size).ravel()
delta = delta - jnp.mean(delta)
# center perturbation
reg_ot_delta_plus = reg_ot(a + eps * delta, b)
reg_ot_delta_minus = reg_ot(a - eps * delta, b)
delta_dot_grad = jnp.sum(delta * grad_reg_ot)
self.assertAllClose(delta_dot_grad,
(reg_ot_delta_plus - reg_ot_delta_minus) / (2 * eps),
rtol=1e-03, atol=1e-02)
def test_separable_grid(self, lse_mode):
"""Two histograms in a grid of size 5 x 6 x 7 in the hypercube^3."""
grid_size = (5, 6, 7)
keys = jax.random.split(self.rng, 2)
a = jax.random.uniform(keys[0], grid_size)
b = jax.random.uniform(keys[1], grid_size)
# adding zero weights to test proper handling, then ravel.
a = jax.ops.index_update(a, 0, 0).ravel()
a = a / jnp.sum(a)
b = jax.ops.index_update(b, 3, 0).ravel()
b = b / jnp.sum(b)
threshold = 0.01
geom = grid.Grid(grid_size=grid_size, epsilon=0.1)
errors = sinkhorn.sinkhorn(
geom, a=a, b=b, threshold=threshold, lse_mode=lse_mode).errors
err = errors[jnp.isfinite(errors)][-1]
self.assertGreater(threshold, err)
def test_apply_cost(self):
grid_size = (5, 6, 7)
geom_grid = grid.Grid(grid_size=grid_size, epsilon=0.1)
x, y, z = np.mgrid[0:grid_size[0], 0:grid_size[1], 0:grid_size[2]]
xyz = jnp.stack([
jnp.array(x.ravel()) / jnp.maximum(1, grid_size[0] - 1),
jnp.array(y.ravel()) / jnp.maximum(1, grid_size[1] - 1),
jnp.array(z.ravel()) / jnp.maximum(1, grid_size[2] - 1),
]).transpose()
geom_mat = pointcloud.PointCloud(xyz, xyz, epsilon=0.1)
vec = jax.random.uniform(self.rng, grid_size).ravel()
self.assertAllClose(geom_mat.apply_cost(vec),
geom_grid.apply_cost(vec))
self.assertAllClose(
geom_grid.apply_cost(vec)[0, :], np.dot(geom_mat.cost_matrix, vec))
def test_grid_vs_euclidean(self, lse_mode):
grid_size = (5, 6, 7)
keys = jax.random.split(self.rng, 2)
a = jax.random.uniform(keys[0], grid_size)
b = jax.random.uniform(keys[1], grid_size)
a = a.ravel() / jnp.sum(a)
b = b.ravel() / jnp.sum(b)
epsilon = 0.1
geometry_grid = grid.Grid(grid_size=grid_size, epsilon=epsilon)
x, y, z = np.mgrid[0:grid_size[0], 0:grid_size[1], 0:grid_size[2]]
xyz = jnp.stack([
jnp.array(x.ravel()) / jnp.maximum(1, grid_size[0] - 1),
jnp.array(y.ravel()) / jnp.maximum(1, grid_size[1] - 1),
jnp.array(z.ravel()) / jnp.maximum(1, grid_size[2] - 1),
]).transpose()
geometry_mat = pointcloud.PointCloud(xyz, xyz, epsilon=epsilon)
out_mat = sinkhorn.sinkhorn(geometry_mat, a=a, b=b, lse_mode=lse_mode)
out_grid = sinkhorn.sinkhorn(geometry_grid, a=a, b=b, lse_mode=lse_mode)
self.assertAllClose(out_mat.reg_ot_cost, out_grid.reg_ot_cost)
def test_apply_transport_grid(self, lse_mode):
grid_size = (5, 6, 7)
keys = jax.random.split(self.rng, 3)
a = jax.random.uniform(keys[0], grid_size)
b = jax.random.uniform(keys[1], grid_size)
a = a.ravel() / jnp.sum(a)
b = b.ravel() / jnp.sum(b)
geom_grid = grid.Grid(grid_size=grid_size, epsilon=0.1)
x, y, z = np.mgrid[0:grid_size[0], 0:grid_size[1], 0:grid_size[2]]
xyz = jnp.stack([
jnp.array(x.ravel()) / jnp.maximum(1, grid_size[0] - 1),
jnp.array(y.ravel()) / jnp.maximum(1, grid_size[1] - 1),
jnp.array(z.ravel()) / jnp.maximum(1, grid_size[2] - 1),
]).transpose()
geom_mat = pointcloud.PointCloud(xyz, xyz, epsilon=0.1)
sink_mat = sinkhorn.sinkhorn(geom_mat, a=a, b=b, lse_mode=lse_mode)
sink_grid = sinkhorn.sinkhorn(geom_grid, a=a, b=b, lse_mode=lse_mode)
batch_a = 3
batch_b = 4
vec_a = jax.random.normal(keys[4], [batch_a,
np.prod(np.array(grid_size))])
vec_b = jax.random.normal(keys[4], [batch_b,
np.prod(grid_size)])
vec_a = vec_a / jnp.sum(vec_a, axis=1)[:, jnp.newaxis]
vec_b = vec_b / jnp.sum(vec_b, axis=1)[:, jnp.newaxis]
mat_transport_t_vec_a = geom_mat.apply_transport_from_potentials(
sink_mat.f, sink_mat.g, vec_a, axis=0)
mat_transport_vec_b = geom_mat.apply_transport_from_potentials(
sink_mat.f, sink_mat.g, vec_b, axis=1)
grid_transport_t_vec_a = geom_grid.apply_transport_from_potentials(
sink_grid.f, sink_grid.g, vec_a, axis=0)
grid_transport_vec_b = geom_grid.apply_transport_from_potentials(
sink_grid.f, sink_grid.g, vec_b, axis=1)
self.assertAllClose(mat_transport_t_vec_a, grid_transport_t_vec_a)
self.assertAllClose(mat_transport_vec_b, grid_transport_vec_b)
self.assertIsNot(jnp.any(jnp.isnan(mat_transport_t_vec_a)), True)
