def compute_outside(self, weights, insides, beta=1.):
outsides = {}
outsides[id(self)] = 0.
topological = list(self.bottomup())
for item in reversed(topological):
if id(item) not in outsides:
# not reachable from top
outsides[id(item)] = cost.IMPOSSIBLE
continue
for ded in item.deds:
if len(ded.ants) == 0:
continue
# p = Pr(ded)
p = weights.dot(ded.dcost)*beta + outsides[id(item)]
for ant in ded.ants:
p += insides[id(ant)]
for ant in ded.ants:
if id(ant) not in outsides:
outsides[id(ant)] = p-insides[id(ant)]
else:
outsides[id(ant)] = cost.add(outsides[id(ant)], p-insides[id(ant)])
if outsides is None:
outsides = {}
if id(self) in outsides:
return outsides
inside = cost.IMPOSSIBLE
for ded in self.deds:
# beta = 0 => uniform
c = weights.dot(ded.dcost)*beta
for ant in ded.ants:
ant.compute_inside(weights, insides)
c += insides[id(ant)]
insides[id(ded)] = c
inside = cost.add(inside, c)
insides[id(self)] = inside
return insides
def compute_inside(self, weights, insides=None, beta=1.):
if insides is None:
insides = {}
if id(self) in insides:
return insides
inside = cost.IMPOSSIBLE
for ded in self.deds:
# beta = 0 => uniform
c = weights.dot(ded.dcost)*beta
for ant in ded.ants:
ant.compute_inside(weights, insides)
c += insides[id(ant)]
insides[id(ded)] = c
inside = cost.add(inside, c)
insides[id(self)] = inside
return insides
def compute_inside(self, weights, insides=None, beta=1.):
if insides is None:
insides = {}
if id(self) in insides:
return insides
inside = cost.IMPOSSIBLE
for ded in self.deds:
# beta = 0 => uniform
c = weights.dot(ded.dcost) * beta
for ant in ded.ants:
ant.compute_inside(weights, insides)
c += insides[id(ant)]
insides[id(ded)] = c
inside = cost.add(inside, c)
insides[id(self)] = inside
return insides
def compute_outside(chart):
# chart is list of items, axiom first, goal last
# requires inside probs
for item in chart:
item.outside = None
chart[-1].outside = 0.0
for item in reversed(chart):
if item.outside is None:
item.outside = cost.IMPOSSIBLE
continue
for ded in item.deds:
if len(ded.ants) > 0:
p = ded.dcost + item.outside
for ant in ded.ants:
p += ant.inside
for ant in ded.ants:
if ant.outside is None:
ant.outside = p-ant.inside
else:
ant.outside = cost.add(ant.outside,p-ant.inside)
def compute_outside(self, weights, insides, beta=1.):
outsides = {}
outsides[id(self)] = 0.
topological = list(self.bottomup())
for item in reversed(topological):
if id(item) not in outsides:
# not reachable from top
outsides[id(item)] = cost.IMPOSSIBLE
continue
for ded in item.deds:
if len(ded.ants) == 0:
continue
# p = Pr(ded)
p = weights.dot(ded.dcost)*beta + outsides[id(item)]
for ant in ded.ants:
p += insides[id(ant)]
for ant in ded.ants:
if id(ant) not in outsides:
outsides[id(ant)] = p-insides[id(ant)]
else:
outsides[id(ant)] = cost.add(outsides[id(ant)], p-insides[id(ant)])
return outsides
def compute_outside(self, weights, insides, beta=1.):
outsides = {}
outsides[id(self)] = 0.
topological = list(self.bottomup())
for item in reversed(topological):
if id(item) not in outsides:
# not reachable from top
outsides[id(item)] = cost.IMPOSSIBLE
continue
for ded in item.deds:
if len(ded.ants) == 0:
continue
# p = Pr(ded)
p = weights.dot(ded.dcost) * beta + outsides[id(item)]
for ant in ded.ants:
p += insides[id(ant)]
for ant in ded.ants:
if id(ant) not in outsides:
outsides[id(ant)] = p - insides[id(ant)]
else:
outsides[id(ant)] = cost.add(outsides[id(ant)],
p - insides[id(ant)])
return outsides
