def graphcuts_sosvm(num_train_samples = 10, len_label = 5, len_feat = 20, num_test_samples = 5):
""" Graph cuts as approximate inference in structured output SVM framework.
Args:
num_train_samples: number of training samples
len_label: number of classes, i.e., size of label space
len_feat: the dimension of the feature vector
num_test_samples: number of testing samples
"""
import time
# generate synthetic dataset
(labels_train, feats_train) = generate_data(num_train_samples, len_label, len_feat)
# compute full-connected edge table
full = np.vstack([x for x in itertools.combinations(range(len_label), 2)])
# define factor types
factor_types = define_factor_types(len_label, len_feat, full)
# create features and labels for factor graph mode
(labels_fg, feats_fg) = build_factor_graph_model(labels_train, feats_train, factor_types, full, GRAPH_CUT)
# create model and register factor types
model = FactorGraphModel(feats_fg, labels_fg, GRAPH_CUT)
for i in range(len(factor_types)):
model.add_factor_type(factor_types[i])
# Training
# the 3rd parameter is do_weighted_averaging, by turning this on,
# a possibly faster convergence rate may be achieved.
# the 4th parameter controls outputs of verbose training information
sgd = StochasticSOSVM(model, labels_fg, True, True)
sgd.set_num_iter(150)
sgd.set_lambda(0.0001)
# train
t0 = time.time()
sgd.train()
t1 = time.time()
w_sgd = sgd.get_w()
#print "SGD took", t1 - t0, "seconds."
# training error
labels_pr = sgd.apply()
ave_loss = evaluation(labels_pr, labels_fg, model)
#print('SGD: Average training error is %.4f' % ave_loss)
# testing error
# generate synthetic testing dataset
(labels_test, feats_test) = generate_data(num_test_samples, len_label, len_feat)
# create features and labels for factor graph mode
(labels_fg_test, feats_fg_test) = build_factor_graph_model(labels_test, feats_test, factor_types, full, GRAPH_CUT)
# set features and labels to sgd
sgd.set_features(feats_fg_test)
sgd.set_labels(labels_fg_test)
# test
labels_pr = sgd.apply()
ave_loss = evaluation(labels_pr, labels_fg_test, model)
def structure_factor_graph_model(tr_samples=samples,
tr_labels=labels,
w=w_all,
ftype=ftype_all):
from modshogun import SOSVMHelper, LabelsFactory
from modshogun import FactorGraphModel, MAPInference, TREE_MAX_PROD
from modshogun import DualLibQPBMSOSVM, StochasticSOSVM
# create model
model = FactorGraphModel(tr_samples, tr_labels, TREE_MAX_PROD, False)
w_truth = [w[0].copy(), w[1].copy(), w[2].copy()]
w[0] = np.zeros(8)
w[1] = np.zeros(4)
w[2] = np.zeros(2)
ftype[0].set_w(w[0])
ftype[1].set_w(w[1])
ftype[2].set_w(w[2])
model.add_factor_type(ftype[0])
model.add_factor_type(ftype[1])
model.add_factor_type(ftype[2])
# --- training with BMRM ---
bmrm = DualLibQPBMSOSVM(model, tr_labels, 0.01)
#bmrm.set_verbose(True)
bmrm.train()
#print 'learned weights:'
#print bmrm.get_w()
#print 'ground truth weights:'
#print w_truth
# evaluation
lbs_bmrm = LabelsFactory.to_structured(bmrm.apply())
acc_loss = 0.0
ave_loss = 0.0
for i in xrange(num_samples):
y_pred = lbs_bmrm.get_label(i)
y_truth = tr_labels.get_label(i)
acc_loss = acc_loss + model.delta_loss(y_truth, y_pred)
ave_loss = acc_loss / num_samples
#print('BMRM: Average training error is %.4f' % ave_loss)
# show primal objs and dual objs
#hbm = bmrm.get_helper()
#print hbm.get_primal_values()
#print hbm.get_eff_passes()
#print hbm.get_train_errors()
# --- training with SGD ---
sgd = StochasticSOSVM(model, tr_labels)
#sgd.set_verbose(True)
sgd.set_lambda(0.01)
sgd.train()
def structure_factor_graph_model(tr_samples = samples, tr_labels = labels, w = w_all, ftype = ftype_all):
from modshogun import SOSVMHelper, LabelsFactory
from modshogun import FactorGraphModel, MAPInference, TREE_MAX_PROD
from modshogun import DualLibQPBMSOSVM, StochasticSOSVM
# create model
model = FactorGraphModel(tr_samples, tr_labels, TREE_MAX_PROD, False)
w_truth = [w[0].copy(), w[1].copy(), w[2].copy()]
w[0] = np.zeros(8)
w[1] = np.zeros(4)
w[2] = np.zeros(2)
ftype[0].set_w(w[0])
ftype[1].set_w(w[1])
ftype[2].set_w(w[2])
model.add_factor_type(ftype[0])
model.add_factor_type(ftype[1])
model.add_factor_type(ftype[2])
# --- training with BMRM ---
bmrm = DualLibQPBMSOSVM(model, tr_labels, 0.01)
#bmrm.set_verbose(True)
bmrm.train()
#print 'learned weights:'
#print bmrm.get_w()
#print 'ground truth weights:'
#print w_truth
# evaluation
eva_bmrm = bmrm.apply()
lbs_bmrm = LabelsFactory.to_structured(eva_bmrm)
acc_loss = 0.0
ave_loss = 0.0
for i in xrange(num_samples):
y_pred = lbs_bmrm.get_label(i)
y_truth = tr_labels.get_label(i)
acc_loss = acc_loss + model.delta_loss(y_truth, y_pred)
ave_loss = acc_loss / num_samples
#print('BMRM: Average training error is %.4f' % ave_loss)
# show primal objs and dual objs
#hbm = bmrm.get_helper()
#print hbm.get_primal_values()
#print hbm.get_eff_passes()
#print hbm.get_train_errors()
# --- training with SGD ---
sgd = StochasticSOSVM(model, tr_labels)
#sgd.set_verbose(True)
sgd.set_lambda(0.01)
sgd.train()
def graphcuts_sosvm(num_train_samples=20,
len_label=10,
len_feat=40,
num_test_samples=10):
""" Graph cuts as approximate inference in structured output SVM framework.
Args:
num_train_samples: number of training samples
len_label: number of classes, i.e., size of label space
len_feat: the dimention of the feature vector
num_test_samples: number of testing samples
"""
import time
# generate synthetic dataset
(labels_train, feats_train) = generate_data(num_train_samples, len_label,
len_feat)
# compute full-connected edge table
full = np.vstack([x for x in itertools.combinations(range(len_label), 2)])
# define factor types
factor_types = define_factor_types(len_label, len_feat, full)
# create features and labels for factor graph mode
(labels_fg, feats_fg) = build_factor_graph_model(labels_train, feats_train,
factor_types, full,
GRAPH_CUT)
# create model and register factor types
model = FactorGraphModel(feats_fg, labels_fg, GRAPH_CUT)
for i in range(len(factor_types)):
model.add_factor_type(factor_types[i])
# Training
# the 3rd parameter is do_weighted_averaging, by turning this on,
# a possibly faster convergence rate may be achieved.
# the 4th parameter controls outputs of verbose training information
sgd = StochasticSOSVM(model, labels_fg, True, True)
sgd.set_num_iter(150)
sgd.set_lambda(0.0001)
# train
t0 = time.time()
sgd.train()
t1 = time.time()
w_sgd = sgd.get_w()
#print "SGD took", t1 - t0, "seconds."
# training error
labels_pr = sgd.apply()
ave_loss = evaluation(labels_pr, labels_fg, model)
#print('SGD: Average training error is %.4f' % ave_loss)
# testing error
# generate synthetic testing dataset
(labels_test, feats_test) = generate_data(num_test_samples, len_label,
len_feat)
# create features and labels for factor graph mode
(labels_fg_test,
feats_fg_test) = build_factor_graph_model(labels_test, feats_test,
factor_types, full, GRAPH_CUT)
# set features and labels to sgd
sgd.set_features(feats_fg_test)
sgd.set_labels(labels_fg_test)
# test
labels_pr = sgd.apply()
ave_loss = evaluation(labels_pr, labels_fg_test, model)