def parallel_function(
dataset_name, method, tol=1e-8, n_outer=15):
# load data
X, y = fetch_libsvm(dataset_name)
# subsample the samples and the features
n_samples, n_features = dict_subsampling[dataset_name]
t_max = dict_t_max[dataset_name]
# t_max = 3600
X, y = clean_dataset(X, y, n_samples, n_features)
alpha_max, n_classes = get_alpha_max(X, y)
log_alpha_max = np.log(alpha_max) # maybe to change alpha max value
algo = ImplicitForward(None, n_iter_jac=2000)
estimator = LogisticRegression(
C=1, fit_intercept=False, warm_start=True, max_iter=30, verbose=False)
model = SparseLogreg(estimator=estimator)
idx_train, idx_val, idx_test = get_splits(X, y)
logit_multiclass = LogisticMulticlass(
idx_train, idx_val, algo, idx_test=idx_test)
monitor = Monitor()
if method == "implicit_forward":
log_alpha0 = np.ones(n_classes) * np.log(0.1 * alpha_max)
optimizer = LineSearch(n_outer=100)
grad_search(
algo, logit_multiclass, model, optimizer, X, y, log_alpha0,
monitor)
elif method.startswith(('random', 'bayesian')):
max_evals = dict_max_eval[dataset_name]
log_alpha_min = np.log(alpha_max) - 7
hyperopt_wrapper(
algo, logit_multiclass, model, X, y, log_alpha_min, log_alpha_max,
monitor, max_evals=max_evals, tol=tol, t_max=t_max, method=method,
size_space=n_classes)
elif method == 'grid_search':
n_alphas = 20
p_alphas = np.geomspace(1, 0.001, n_alphas)
p_alphas = np.tile(p_alphas, (n_classes, 1))
for i in range(n_alphas):
log_alpha_i = np.log(alpha_max * p_alphas[:, i])
logit_multiclass.get_val(
model, X, y, log_alpha_i, None, monitor, tol)
monitor.times = np.array(monitor.times).copy()
monitor.objs = np.array(monitor.objs).copy()
monitor.acc_vals = np.array(monitor.acc_vals).copy()
monitor.acc_tests = np.array(monitor.acc_tests).copy()
monitor.log_alphas = np.array(monitor.log_alphas).copy()
return (
dataset_name, method, tol, n_outer, monitor.times, monitor.objs,
monitor.acc_vals, monitor.acc_tests, monitor.log_alphas, log_alpha_max,
n_samples, n_features, n_classes)
def parallel_function(dataset_name,
method,
tol=1e-5,
n_outer=50,
tolerance_decrease='constant'):
# load data
X_train, X_val, X_test, y_train, y_val, y_test = get_data(dataset_name)
n_samples, _ = X_train.shape
# compute alpha_max
alpha_max = np.abs(X_train.T @ y_train).max() / n_samples
if model_name == "logreg":
alpha_max /= 2
alpha_min = alpha_max / 10_000
log_alpha_max = np.log(alpha_max)
log_alpha_min = np.log(alpha_min)
log_alpha0 = np.log(0.1 * alpha_max)
if model_name == "lasso":
model = Lasso(X_train, y_train)
elif model_name == "logreg":
model = SparseLogreg(X_train, y_train)
try:
n_outer = dict_n_outers[dataset_name, method]
except Exception:
n_outer = 20
size_loop = 2
for _ in range(size_loop):
if model_name == "lasso":
criterion = HeldOutMSE(X_val,
y_val,
model,
X_test=X_test,
y_test=y_test)
elif model_name == "logreg":
criterion = HeldOutLogistic(X_val,
y_val,
model,
X_test=X_test,
y_test=y_test)
algo = dict_algo[method](criterion)
monitor = Monitor()
if method == 'grid_search':
log_alphas = np.log(np.geomspace(alpha_max, alpha_min, num=100))
grid_search(algo,
None,
None,
monitor,
log_alphas=log_alphas,
tol=tol)
elif method == 'random':
grid_search(algo,
log_alpha_max,
log_alpha_min,
monitor,
tol=tol,
max_evals=n_alphas,
t_max=dict_t_max[dataset_name])
elif method in ("bayesian"):
hyperopt_wrapper(algo,
log_alpha_min,
log_alpha_max,
monitor,
max_evals=n_alphas,
tol=tol,
method='bayesian',
t_max=dict_t_max[dataset_name])
else:
# do line search to find the optimal lambda
grad_search(algo,
log_alpha0,
monitor,
n_outer=n_outer,
tol=tol,
tolerance_decrease=tolerance_decrease,
t_max=dict_t_max[dataset_name])
monitor.times = np.array(monitor.times)
monitor.objs = np.array(monitor.objs)
monitor.objs_test = np.array(monitor.objs_test)
monitor.log_alphas = np.array(monitor.log_alphas)
return (dataset_name, method, tol, n_outer, tolerance_decrease,
monitor.times, monitor.objs, monitor.objs_test, monitor.log_alphas,
norm(y_val), norm(y_test), log_alpha_max, model_name)
def parallel_function(dataset_name,
method,
tol=1e-5,
n_outer=50,
tolerance_decrease='constant'):
t_max = dict_tmax[dataset_name]
# load data
X_train, X_val, X_test, y_train, y_val, y_test = get_data(dataset_name)
n_samples, n_features = X_train.shape
# compute alpha_max
alpha_max = np.abs(X_train.T @ y_train).max() / n_samples
log_alpha0 = np.log(0.1 * alpha_max)
idx_nz = scipy.sparse.linalg.norm(X_train, axis=0) != 0
L_min = scipy.sparse.linalg.norm(X_train[:, idx_nz],
axis=0).min()**2 / n_samples
log_alpha0_mcp = np.array([log_alpha0, np.log(2 / L_min)])
list_log_alphas = np.log(alpha_max * np.geomspace(1, 0.0001, 100))
list_log_gammas = np.log(np.geomspace(1.1 / L_min, 1000 / L_min, 5))
try:
n_outer = dict_n_outers[dataset_name, method]
except Exception:
n_outer = 50
if dataset_name == "rcv1":
size_loop = 2
else:
size_loop = 1
for i in range(size_loop):
monitor = Monitor()
warm_start = WarmStart()
if method == 'grid_search':
# n_alpha = 100
# p_alphas = np.geomspace(1, 0.0001, n_alpha)
grid_searchMCP(X_train,
y_train,
list_log_alphas,
list_log_gammas,
X_val,
y_val,
X_test,
y_test,
tol,
monitor=monitor)
elif method in ("bayesian", "random"):
monitor = hyperopt_lasso(X_train,
y_train,
log_alpha0,
X_val,
y_val,
X_test,
y_test,
tol,
max_evals=n_outer,
method=method)
else:
# do line search to find the optimal lambda
log_alpha, val, grad = grad_search(X_train,
y_train,
log_alpha0_mcp,
X_val,
y_val,
X_test,
y_test,
tol,
monitor,
method=method,
maxit=10000,
n_outer=n_outer,
warm_start=warm_start,
niter_jac=100,
model="mcp",
t_max=t_max)
del log_alpha, val, grad # as not used
monitor.times = np.array(monitor.times)
monitor.objs = np.array(monitor.objs)
monitor.objs_test = np.array(monitor.objs_test)
monitor.log_alphas = np.array(monitor.log_alphas)
return (dataset_name, method, tol, n_outer, tolerance_decrease,
monitor.times, monitor.objs, monitor.objs_test, monitor.log_alphas,
norm(y_val), norm(y_test))