def test_step_type_setting(self):
"""...Test that SVRG step_type parameter behaves correctly
"""
svrg = SVRG()
coeffs0 = weights_sparse_gauss(20, nnz=5, dtype=self.dtype)
interc0 = None
X, y = SimuLogReg(coeffs0,
interc0,
n_samples=3000,
verbose=False,
seed=123,
dtype=self.dtype).simulate()
model = ModelLogReg().fit(X, y)
svrg.set_model(model)
self.assertEqual(svrg.step_type, 'fixed')
self.assertEqual(svrg._solver.get_step_type(), SVRG_StepType_Fixed)
svrg = SVRG(step_type='bb')
svrg.set_model(model)
self.assertEqual(svrg.step_type, 'bb')
self.assertEqual(svrg._solver.get_step_type(),
SVRG_StepType_BarzilaiBorwein)
svrg.step_type = 'fixed'
self.assertEqual(svrg.step_type, 'fixed')
self.assertEqual(svrg._solver.get_step_type(), SVRG_StepType_Fixed)
svrg.step_type = 'bb'
self.assertEqual(svrg.step_type, 'bb')
self.assertEqual(svrg._solver.get_step_type(),
SVRG_StepType_BarzilaiBorwein)
def test_sdca_identity_poisreg(self):
"""...Test SDCA on specific case of Poisson regression with
indentity link
"""
l_l2sq = 1e-3
n_samples = 10000
n_features = 3
np.random.seed(123)
weight0 = np.random.rand(n_features)
features = np.random.rand(n_samples, n_features)
for intercept in [None, 0.45]:
if intercept is None:
fit_intercept = False
else:
fit_intercept = True
simu = SimuPoisReg(weight0, intercept=intercept, features=features,
n_samples=n_samples, link='identity',
verbose=False)
features, labels = simu.simulate()
model = ModelPoisReg(fit_intercept=fit_intercept, link='identity')
model.fit(features, labels)
sdca = SDCA(l_l2sq=l_l2sq, max_iter=100, verbose=False, tol=1e-14,
seed=Test.sto_seed)
sdca.set_model(model).set_prox(ProxZero())
start_dual = np.sqrt(sdca._rand_max * l_l2sq)
start_dual = start_dual * np.ones(sdca._rand_max)
sdca.solve(start_dual)
# Check that duality gap is 0
self.assertAlmostEqual(
sdca.objective(sdca.solution),
sdca.dual_objective(sdca.dual_solution))
# Check that original vector is approximatively retrieved
if fit_intercept:
original_coeffs = np.hstack((weight0, intercept))
else:
original_coeffs = weight0
np.testing.assert_array_almost_equal(original_coeffs,
sdca.solution, decimal=1)
# Ensure that we solve the same problem as other solvers
svrg = SVRG(max_iter=100, verbose=False, tol=1e-14,
seed=Test.sto_seed)
svrg.set_model(model).set_prox(ProxL2Sq(l_l2sq))
svrg.solve(0.5 * np.ones(model.n_coeffs), step=1e-2)
np.testing.assert_array_almost_equal(svrg.solution, sdca.solution,
decimal=4)
def test_dense_and_sparse_match(self):
"""...Test in SVRG that dense and sparse code matches in all possible
settings
"""
variance_reductions = ['last', 'rand']
rand_types = ['perm', 'unif']
seed = 123
tol = 0.
max_iter = 50
n_samples = 500
n_features = 20
# Crazy prox examples
proxs = [
ProxTV(strength=1e-2, range=(5, 13),
positive=True).astype(self.dtype),
ProxElasticNet(strength=1e-2, ratio=0.9).astype(self.dtype),
ProxEquality(range=(0, n_features)).astype(self.dtype),
ProxL1(strength=1e-3, range=(5, 17)).astype(self.dtype),
ProxL1w(strength=1e-3, weights=np.arange(5, 17, dtype=np.double),
range=(5, 17)).astype(self.dtype),
]
for intercept in [-1, None]:
X, y = self.simu_linreg_data(dtype=self.dtype, interc=intercept,
n_features=n_features,
n_samples=n_samples)
fit_intercept = intercept is not None
model_dense, model_spars = self.get_dense_and_sparse_linreg_model(
X, y, dtype=self.dtype, fit_intercept=fit_intercept)
step = 1 / model_spars.get_lip_max()
for variance_reduction, rand_type, prox in product(
variance_reductions, rand_types, proxs):
solver_sparse = SVRG(step=step, tol=tol, max_iter=max_iter,
verbose=False,
variance_reduction=variance_reduction,
rand_type=rand_type, seed=seed)
solver_sparse.set_model(model_spars).set_prox(prox)
solver_dense = SVRG(step=step, tol=tol, max_iter=max_iter,
verbose=False,
variance_reduction=variance_reduction,
rand_type=rand_type, seed=seed)
solver_dense.set_model(model_dense).set_prox(prox)
solver_sparse.solve()
solver_dense.solve()
places = 7
if self.dtype is "float32":
places = 3
np.testing.assert_array_almost_equal(solver_sparse.solution,
solver_dense.solution,
decimal=places)
def test_set_model(self):
"""...Test SVRG set_model
"""
X, y = self.simu_linreg_data()
_, model_spars = self.get_dense_and_sparse_linreg_model(X, y)
svrg = SVRG(variance_reduction='avg')
msg = "'avg' variance reduction cannot be used with sparse datasets. " \
"Please change `variance_reduction` before passing sparse data."
with catch_warnings(record=True) as w:
simplefilter('always')
svrg.set_model(model_spars)
self.assertEqual(len(w), 1)
self.assertTrue(issubclass(w[0].category, UserWarning))
self.assertEqual(str(w[0].message), msg)
def test_convergence_with_lags(self):
"""Test longitudinal multinomial model convergence."""
n_intervals = 10
n_lags = 3
n_samples = 1500
n_features = 3
sim = SimuSCCS(n_samples, n_intervals, n_features, n_lags, None,
True, "short", seed=42, verbose=False)
X, y, censoring, coeffs = sim.simulate()
X = LongitudinalFeaturesLagger(n_lags=n_lags) \
.fit_transform(X, censoring)
model = ModelSCCS(n_intervals=n_intervals,
n_lags=n_lags).fit(X, y, censoring)
solver = SVRG(max_iter=15, verbose=False)
solver.set_model(model).set_prox(ProxZero())
coeffs_svrg = solver.solve(step=1 / model.get_lip_max())
np.testing.assert_almost_equal(coeffs, coeffs_svrg, decimal=1)
def run_solvers(model, l_l2sq):
try:
svrg_step = 1. / model.get_lip_max()
except AttributeError:
svrg_step = 1e-3
try:
gd_step = 1. / model.get_lip_best()
except AttributeError:
gd_step = 1e-1
bfgs = BFGS(verbose=False, tol=1e-13)
bfgs.set_model(model).set_prox(ProxL2Sq(l_l2sq))
bfgs.solve()
bfgs.history.set_minimizer(bfgs.solution)
bfgs.history.set_minimum(bfgs.objective(bfgs.solution))
bfgs.solve()
svrg = SVRG(step=svrg_step, verbose=False, tol=1e-10, seed=seed)
svrg.set_model(model).set_prox(ProxL2Sq(l_l2sq))
svrg.history.set_minimizer(bfgs.solution)
svrg.history.set_minimum(bfgs.objective(bfgs.solution))
svrg.solve()
sdca = SDCA(l_l2sq, verbose=False, seed=seed, tol=1e-10)
sdca.set_model(model).set_prox(ProxZero())
sdca.history.set_minimizer(bfgs.solution)
sdca.history.set_minimum(bfgs.objective(bfgs.solution))
sdca.solve()
gd = GD(verbose=False, tol=1e-10, step=gd_step, linesearch=False)
gd.set_model(model).set_prox(ProxL2Sq(l_l2sq))
gd.history.set_minimizer(bfgs.solution)
gd.history.set_minimum(bfgs.objective(bfgs.solution))
gd.solve()
agd = AGD(verbose=False, tol=1e-10, step=gd_step, linesearch=False)
agd.set_model(model).set_prox(ProxL2Sq(l_l2sq))
agd.history.set_minimizer(bfgs.solution)
agd.history.set_minimum(bfgs.objective(bfgs.solution))
agd.solve()
return bfgs, svrg, sdca, gd, agd
def test_convergence_with_lags(self):
"""Test longitudinal multinomial model convergence."""
n_intervals = 10
n_samples = 800
n_features = 2
n_lags = np.repeat(2, n_features).astype(dtype="uint64")
sim = SimuSCCS(n_samples,
n_intervals,
n_features,
n_lags,
None,
"multiple_exposures",
seed=42)
_, X, y, censoring, coeffs = sim.simulate()
coeffs = np.hstack(coeffs)
X, _, _ = LongitudinalFeaturesLagger(n_lags=n_lags) \
.fit_transform(X, censoring)
model = ModelSCCS(n_intervals=n_intervals,
n_lags=n_lags).fit(X, y, censoring)
solver = SVRG(max_iter=15, verbose=False)
solver.set_model(model).set_prox(ProxZero())
coeffs_svrg = solver.solve(step=1 / model.get_lip_max())
np.testing.assert_almost_equal(coeffs, coeffs_svrg, decimal=1)
def test_variance_reduction_setting(self):
"""...Test that SVRG variance_reduction parameter behaves correctly
"""
svrg = SVRG()
self.assertEqual(svrg.variance_reduction, 'last')
self.assertEqual(svrg._solver.get_variance_reduction(),
SVRG_VarianceReductionMethod_Last)
svrg = SVRG(variance_reduction='rand')
self.assertEqual(svrg.variance_reduction, 'rand')
self.assertEqual(svrg._solver.get_variance_reduction(),
SVRG_VarianceReductionMethod_Random)
svrg.variance_reduction = 'avg'
self.assertEqual(svrg.variance_reduction, 'avg')
self.assertEqual(svrg._solver.get_variance_reduction(),
SVRG_VarianceReductionMethod_Average)
svrg.variance_reduction = 'rand'
self.assertEqual(svrg.variance_reduction, 'rand')
self.assertEqual(svrg._solver.get_variance_reduction(),
SVRG_VarianceReductionMethod_Random)
svrg.variance_reduction = 'last'
self.assertEqual(svrg.variance_reduction, 'last')
self.assertEqual(svrg._solver.get_variance_reduction(),
SVRG_VarianceReductionMethod_Last)
msg = '^variance_reduction should be one of "avg, last, rand", ' \
'got "stuff"$'
with self.assertRaisesRegex(ValueError, msg):
svrg = SVRG(variance_reduction='stuff')
with self.assertRaisesRegex(ValueError, msg):
svrg.variance_reduction = 'stuff'
X, y = self.simu_linreg_data()
model_dense, model_spars = self.get_dense_and_sparse_linreg_model(X, y)
try:
svrg.set_model(model_dense)
svrg.variance_reduction = 'avg'
svrg.variance_reduction = 'last'
svrg.variance_reduction = 'rand'
svrg.set_model(model_spars)
svrg.variance_reduction = 'last'
svrg.variance_reduction = 'rand'
except Exception:
self.fail('Setting variance_reduction in these cases should have '
'been ok')
msg = "'avg' variance reduction cannot be used with sparse datasets"
with catch_warnings(record=True) as w:
simplefilter('always')
svrg.set_model(model_spars)
svrg.variance_reduction = 'avg'
self.assertEqual(len(w), 1)
self.assertTrue(issubclass(w[0].category, UserWarning))
self.assertEqual(str(w[0].message), msg)
X, y = SimuLogReg(weights=weights0, intercept=intercept0,
n_samples=n_samples, seed=123, verbose=False).simulate()
model = ModelLogReg(fit_intercept=True).fit(X, y)
prox = ProxElasticNet(strength=1e-3, ratio=0.5, range=(0, n_features))
x0 = np.zeros(model.n_coeffs)
optimal_step = 1 / model.get_lip_max()
tested_steps = [optimal_step, 1e-2 * optimal_step, 10 * optimal_step]
solvers = []
solver_labels = []
for step in tested_steps:
svrg = SVRG(max_iter=30, tol=1e-10, verbose=False)
svrg.set_model(model).set_prox(prox)
svrg.solve(step=step)
svrg_bb = SVRG(max_iter=30, tol=1e-10, verbose=False, step_type='bb')
svrg_bb.set_model(model).set_prox(prox)
svrg_bb.solve(step=step)
solvers += [svrg, svrg_bb]
optimal_factor = step / optimal_step
if optimal_factor != 1:
solver_labels += ['SVRG {:.2g} * optimal step'.format(optimal_factor),
'SVRG BB {:.2g} * optimal step'.format(optimal_factor)]
else:
solver_labels += ['SVRG optimal step'.format(optimal_factor),
'SVRG BB optimal step'.format(optimal_factor)]