def test_max_marginals():
"""
Test that max-marginals are correct.
"""
for h in hypergraphs():
w = utils.random_viterbi_potentials(h)
print w.show(h)
path = ph.best_path(h, w)
best = w.dot(path)
print "BEST"
print "\n".join(["%20s : %s"%(edge.label, w[edge]) for edge in path.edges])
print best
nt.assert_not_equal(best, 0.0)
max_marginals = ph.compute_marginals(h, w)
for node in h.nodes:
other = max_marginals[node]
nt.assert_less_equal(other, best + 1e-4)
for edge in h.edges:
other = max_marginals[edge]
nt.assert_less_equal(other, best + 1e-4)
if edge in path:
nt.assert_almost_equal(other, best)
def inference(self, x, w, relaxed=False):
relaxed = relaxed or self._use_relaxed
if self._debug: a = time.time()
hypergraph = self._build_hypergraph(x)
if self._debug: print >>sys.stderr, "BUILD HYPERGRAPH:", time.time() -a
if self._debug: a = time.time()
potentials = self._build_potentials(hypergraph, x, w)
if self._debug: print >>sys.stderr, "BUILD POTENTIALS:", time.time() - a
if not self._constrained:
if self._debug: a = time.time()
path = ph.best_path(hypergraph, potentials)
if self._debug: print >>sys.stderr, "BEST PATH:", time.time() - a
else:
if self._debug: a = time.time()
constraints = self.constraints(x, hypergraph)
hyperlp = lp.HypergraphLP.make_lp(hypergraph, potentials, integral=not relaxed)
hyperlp.add_constraints(constraints)
if self._debug: print >>sys.stderr, "BUILD LP:", time.time() - a
if self._debug: a = time.time()
if self._use_gurobi:
hyperlp.solve(pulp.solvers.GUROBI(mip=1 if not relaxed else 0))
else:
hyperlp.solve(pulp.solvers.GLPK(mip=1 if not relaxed else 0 ))
if self._debug: print >>sys.stderr, "SOLVE LP:", time.time() - a
if relaxed:
path = hyperlp.decode_fractional()
else:
path = hyperlp.path
if self._debug: print
y = set([edge.label for edge in path])
return y
def fn(x):
mod_weights = ph.pairwise_dot(potentials, x);
dual_weights = weight_potentials.times(mod_weights)
path = ph.best_path(graph, dual_weights)
score = dual_weights.dot(path)
vec = potentials.dot(path)
subgrad = np.zeros(len(x))
for i, j in vec:
subgrad[i] = j
return score, subgrad, path
def test_subgradient():
for h in hypergraphs():
w = utils.random_log_viterbi_potentials(h)
constraints, edge = random_have_constraint(h)
path = ph.best_path(h, w)
match = constraints.check(path)
if edge not in path:
nt.assert_equal(match[0], "have")
cpath = opt.best_constrained_path(h, w,
constraints)
assert edge in cpath
def test_pruning():
for h in hypergraphs():
w = utils.random_viterbi_potentials(h)
original_path = ph.best_path(h, w)
new_hyper, new_potentials = ph.prune_hypergraph(h, w, -0.99)
prune_path = ph.best_path(new_hyper, new_potentials)
assert len(original_path.edges) > 0
for edge in original_path.edges:
assert edge in prune_path
valid_path(new_hyper, prune_path)
original_score = w.dot(original_path)
print original_score
print new_potentials.dot(prune_path)
nt.assert_almost_equal(original_score,
new_potentials.dot(prune_path))
# Test pruning amount.
prune = 0.001
max_marginals = ph.compute_marginals(h, w)
new_hyper, new_potentials = ph.prune_hypergraph(h, w, prune)
assert (len(new_hyper.edges) > 0)
original_edges = {}
for edge in h.edges:
original_edges[edge.label] = edge
new_edges = {}
for edge in new_hyper.edges:
new_edges[edge.label] = edge
for name, edge in new_edges.iteritems():
orig = original_edges[name]
nt.assert_almost_equal(w[orig], new_potentials[edge])
m = max_marginals[orig]
nt.assert_greater(m, prune)
def backtrace(self, item):
self.hypergraph = self.chart.finish()
scores = np.zeros(len(self.hypergraph.edges))
self.skips = np.zeros(len(self.hypergraph.edges))
self.scores = scores
for edge_num, label, tail_labels in self.hypergraph.node_labels():
scores[edge_num] = self.score(label, len(tail_labels))
self.pot = ph.LogViterbiPotentials(self.hypergraph) \
.from_array(scores)
if self.m != None:
counts = np.zeros(len(self.hypergraph.edges), dtype=np.int32)
if self.m > (self.n / 2):
m2 = self.n - self.m
for edge_num, label, tail_labels in self.hypergraph.node_labels():
typ, d, s, t, _ = label
if typ == interface.Tri and d == interface.Right and len(tail_labels) == 1:
if t != s:
counts[edge_num] = (t - s)
self.counts = ph.CountingPotentials(self.hypergraph) \
.from_array(counts)
hmap = ph.extend_hypergraph_by_count(self.hypergraph, self.counts, 0, m2, m2)
else:
for edge_num, label in self.hypergraph.head_labels():
counts[edge_num] = 1 if (label[0] == interface.Trap) else 0
self.counts = ph.CountingPotentials(self.hypergraph) \
.from_array(counts)
hmap = ph.extend_hypergraph_by_count(self.hypergraph, self.counts, 0, self.m, self.m)
new_pot = self.pot.up_project(hmap.domain_hypergraph, hmap)
path = ph.best_path(hmap.domain_hypergraph, new_pot)
else:
path = ph.best_path(self.hypergraph, self.pot)
return [node.label for node in path.nodes]
def test_best_path():
"""
Test viterbi path finding.
"""
for h in hypergraphs():
w = utils.random_log_viterbi_potentials(h)
path = ph.best_path(h, w)
nt.assert_not_equal(w.dot(path), 0.0)
valid_path(h, path)
same = False
for other_path in utils.all_paths(h):
assert w.dot(path) >= w.dot(other_path)
if path == other_path: same = True
assert same
def regen(self, penalty, counts):
# scores = np.zeros(len(self.hypergraph.edges))
# for edge_num, label, tail_labels in self.hypergraph.node_labels():
# #scores[edge_num] = self.score(label, len(self.hypergraph.edges[edge_num].tail))
# #len(self.hypergraph.edges[edge_num].tail)
# #scores[edge_num] = self.score(label, len(tail_labels))
# typ, d, s, t, _ = label
# if typ == interface.Trap:
# if d == interface.Left: s, t = t, s
# scores[edge_num] = scorer.arc_score(s, t)
# if typ == interface.Tri and d == interface.Right and len(tail_labels) == 1:
# scores[edge_num] = scorer.bigram_score(s, t+1) - \
# ((t+1 - s - 1) * scorer.skip_penalty) if s != t+1 else 0.0
self.pot = ph.LogViterbiPotentials(self.hypergraph) \
.from_array(self.scores + (penalty * counts))
path = ph.best_path(self.hypergraph, self.pot)
return [node.label for node in path.nodes]
def test_outside():
"""
Test outside chart properties.
"""
for h in hypergraphs():
w = utils.random_viterbi_potentials(h)
path = ph.best_path(h, w)
chart = ph.inside_values(h, w)
best = w.dot(path)
nt.assert_not_equal(best, 0.0)
out_chart = ph.outside_values(h, w, chart)
for node in h.nodes:
other = chart[node] * out_chart[node]
nt.assert_less_equal(other, best + 1e-4)
for edge in path.edges:
for node in edge.tail:
if node.is_terminal:
nt.assert_almost_equal(other, best)
def test_variables():
"""
Test variable constraint checking.
"""
for h in hypergraphs():
w = utils.random_viterbi_potentials(h)
variables, edge = random_constraint_trans(h)
path = ph.best_path(h, w)
match = list(variables.check(path))
if edge not in path:
print "Should not have", edge.id
assert "have" in match
assert "not" not in match
else:
print "Should have", edge.id
assert "have" not in match
nt.assert_equal(len(match), 1)
def parse(self, sentence):
words = sentence.strip().split(" ")
n = len(words)
nodes = {}
for i, word in enumerate(words):
if word not in self.terminals or self.terminals[word] < 5:
words[i] = '_RARE_'
sentence_graph = ph.Hypergraph()
with sentence_graph.builder() as b:
for i, word in enumerate(words, start=1):
relevant_rules = (rule for rule in self.get_unary_rules()
if rule.rhs_first == word)
r = RuleSpan(word, i, i)
nodes[r] = b.add_node(label=r)
for rule in relevant_rules:
nodes[RuleSpan(rule.lhs, i, i)] = b.add_node(
[([nodes[RuleSpan(rule.rhs_first, i, i)]], rule)],
label=RuleSpan(rule.lhs, i, i))
for l in xrange(1, n):
for i in xrange(1, n-l+1):
j = i+l
for nonterminal in list(self.multinomials) + ["S"]:
edgelist = []
for rule in self.multinomials[nonterminal]:
if rule.unary:
continue
for s in xrange(i, j):
rule_span1 = RuleSpan(rule.rhs_first, i, s)
rule_span2 = RuleSpan(rule.rhs_second, s+1, j)
if rule_span1 in nodes.keys()\
and rule_span2 in nodes.keys():
edgelist.append((
[nodes[rule_span1],
nodes[rule_span2]],
rule))
if edgelist:
rs = RuleSpan(nonterminal, i, j)
nodes[rs] = b.add_node(edgelist, label=rs)
weights = ph.Potentials(sentence_graph).build(self.build_potentials)
path = ph.best_path(sentence_graph, weights)
for edge in path.edges:
print edge.label, self.build_potentials(edge.label)
def test_lp():
import pydecode.lp as lp
for h in hypergraphs():
w = utils.random_log_viterbi_potentials(h)
g = lp.HypergraphLP.make_lp(h, w)
g.solve()
path = g.path
opath = ph.best_path(h, w)
nt.assert_almost_equal(w.dot(path), w.dot(opath))
for edge in path.edges:
assert edge in opath
# Constraint.
constraints, edge = random_have_constraint(h)
g = lp.HypergraphLP.make_lp(h, w)
g.add_constraints(constraints)
g.solve()
assert edge in g.path
# 0.398276388645 # 0.686978042126 # 0.0620245561004 # 0.156915932894 # 0.227964177728 # 0.761591732502 # 0.0153166977689 # 0.402361214161 # 0.468028366566 # 0.351031720638 # 0.130741521716 # # In[55]: path = hyper.best_path(hyper1, potentials) potentials.dot(path) # Out[55]: # 3.458035945892334 # In[56]: import pydecode.optimization as opt cpath = opt.best_constrained_path(hyper1, potentials, constraints) # In[57]:
def best_path(self):
viterbi_potentials = self.viterbi_potentials()
return ph.best_path(self.hypergraph, viterbi_potentials)
def test_diff_potentials_fail():
h1, w1 = random_hypergraph()
h2, w2 = random_hypergraph()
ph.best_path(h1, w2)
for edge in hyper1.edges:
print hyper1.label(edge), potentials[edge]
# Out[]:
# First Edge 1.0
# Second Edge 5.0
# Third Edge 5.0
#
# We use the best path.
# In[ ]:
path = ph.best_path(hyper1, potentials)
# In[ ]:
print potentials.dot(path)
# Out[]:
# 6.0
#
# In[ ]:
display.HypergraphFormatter(hyper1).to_ipython()
n3 = b.add_node(label = "c")
n4 = b.add_node(label = "d")
n5 = b.add_node((([n1, n2], "edge1"),), label = "e")
b.add_node([([n5], "edge3"), ([n3, n4], "edge2")], label = "root")
def build_potentials(label):
return {"edge1" : 3, "edge2" : 1, "edge3" : 1}[label]
potentials = ph.Potentials(hyp).build(build_potentials)
# Draw the graph
# In[3]:
display.HypergraphPotentialFormatter(hyp, potentials).to_ipython()
# Out[3]:
# <IPython.core.display.Image at 0x2fb1410>
# In[4]:
path = ph.best_path(hyp, potentials)
display.HypergraphPathFormatter(hyp, [path]).to_ipython()
# Out[4]:
# <IPython.core.display.Image at 0x33e2910>
TypeError: not all arguments converted during string formatting
# In[ ]:
def build_potentials(arc):
print arc
return random.random()
potentials = ph.Potentials(hypergraph).build(build_potentials)
# phyper, ppotentials = ph.prune_hypergraph(hypergraph, potentials, 0.5)
# In[ ]:
path = ph.best_path(hypergraph, potentials)
best = potentials.dot(path)
maxmarginals = ph.compute_marginals(hypergraph, potentials)
avg = 0.0
for edge in hypergraph.edges:
avg += float(maxmarginals[edge])
avg = avg / float(len(hypergraph.edges))
thres = ((0.9) * best + (0.1) * avg)
kept = set()
for edge in hypergraph.edges:
score = float(maxmarginals[edge])
if score >= thres:
kept.add(edge.id)
for edge in hyper1.edges:
print hyper1.label(edge), weights[edge]
# Out[14]:
# First Edge 1.0
# Second Edge 5.0
# Third Edge 5.0
#
# We use the best path.
# In[15]:
path = ph.best_path(hyper1, weights)
# In[16]:
print weights.dot(path)
# Out[16]:
# 6.0
#
# In[17]:
display.HypergraphFormatter(hyper1).to_ipython()
def decode_fractional(self):
vec = [pulp.value(self.edge_vars[edge.id])
for edge in self.hypergraph.edges]
weights = ph.LogViterbiPotentials(self.hypergraph).from_vector(vec)
return ph.best_path(self.hypergraph, weights)
