def __init__(self, mrf, queries=ALL, state=None, **params):
MCMCInference.__init__(self, mrf, queries, **params)
if state is None:
self.state = self.random_world(self.mrf.evidence)
else:
self.state = state
self.sum = 0
self.var2gf = defaultdict(set)
self.weights = list(self.mrf.mln.weights)
formulas = []
for f in self.mrf.formulas:
if f.weight < 0:
f_ = self.mrf.mln.logic.negate(f)
f_.weight = -f.weight
formulas.append(f_.nnf())
grounder = FastConjunctionGrounding(mrf,
formulas=formulas,
simplify=True,
unsatfailure=True)
for gf in grounder.itergroundings():
if isinstance(gf, Logic.TrueFalse): continue
vars_ = set(map(lambda a: self.mrf.variable(a).idx, gf.gndatoms()))
for v in vars_:
self.var2gf[v].add(gf)
self.sum += (self.hardw if gf.weight == HARD else
gf.weight) * (1 - gf(self.state))
def __init__(self, mrf, queries=ALL, **params):
MCMCInference.__init__(self, mrf, queries, **params)
self.var2gf = defaultdict(set)
grounder = FastConjunctionGrounding(mrf, simplify=True, unsatfailure=True, cache=None)
for gf in grounder.itergroundings():
if isinstance(gf, Logic.TrueFalse): continue
vars_ = set(map(lambda a: self.mrf.variable(a).idx, gf.gndatoms()))
for v in vars_: self.var2gf[v].add(gf)
def __init__(self, mrf, queries=ALL, **params):
MCMCInference.__init__(self, mrf, queries, **params)
self.var2gf = defaultdict(set)
grounder = FastConjunctionGrounding(mrf, simplify=True, unsatfailure=True, cache=None)
for gf in grounder.itergroundings():
if isinstance(gf, Logic.TrueFalse): continue
vars_ = set(map(lambda a: self.mrf.variable(a).idx, gf.gndatoms()))
for v in vars_: self.var2gf[v].add(gf)
def __init__(self, mrf, queries=ALL, state=None, **params):
MCMCInference.__init__(self, mrf, queries, **params)
if state is None:
self.state = self.random_world(self.mrf.evidence)
else:
self.state = state
self.sum = 0
self.var2gf = defaultdict(set)
self.weights = list(self.mrf.mln.weights)
formulas = []
for f in self.mrf.formulas:
if f.weight < 0:
f_ = self.mrf.mln.logic.negate(f)
f_.weight = - f.weight
formulas.append(f_.nnf())
grounder = FastConjunctionGrounding(mrf, formulas=formulas, simplify=True, unsatfailure=True)
for gf in grounder.itergroundings():
if isinstance(gf, Logic.TrueFalse): continue
vars_ = set(map(lambda a: self.mrf.variable(a).idx, gf.gndatoms()))
for v in vars_: self.var2gf[v].add(gf)
self.sum += (self.hardw if gf.weight == HARD else gf.weight) * (1 - gf(self.state))
def _run(self, **params):
'''
infer one or more probabilities P(F1 | F2)
what: a ground formula (string) or a list of ground formulas (list of strings) (F1)
given: a formula as a string (F2)
set evidence according to given conjunction (if any)
'''
# if softEvidence is None:
# self.softEvidence = self.mln.softEvidence
# else:
# self.softEvidence = softEvidence
# initialize chains
chains = MCMCInference.ChainGroup(self)
for i in range(self.chains):
chain = GibbsSampler.Chain(self, self.queries)
chains.chain(chain)
# if self.softEvidence is not None:
# chain.setSoftEvidence(self.softEvidence)
# do Gibbs sampling
# if verbose and details: print "sampling..."
converged = 0
steps = 0
if self.verbose:
bar = ProgressBar(color='green', steps=self.maxsteps)
while converged != self.chains and steps < self.maxsteps:
converged = 0
steps += 1
for chain in chains.chains:
chain.step()
if self.verbose:
bar.inc()
bar.label('%d / %d' % (steps, self.maxsteps))
# if self.useConvergenceTest:
# if chain.converged and numSteps >= minSteps:
# converged += 1
# if verbose and details:
# if numSteps % infoInterval == 0:
# print "step %d (fraction converged: %.2f)" % (numSteps, float(converged) / numChains)
# if numSteps % resultsInterval == 0:
# chainGroup.getResults()
# chainGroup.printResults(shortOutput=True)
# get the results
return chains.results()[0]
def __init__(self, mrf, queries=ALL, **params):
MCMCInference.__init__(self, mrf, queries, **params)
self._weight_backup = list(self.mrf.mln.weights)
def _run(self):
'''
p: probability of a greedy (WalkSAT) move
initAlgo: algorithm to use in order to find an initial state that satisfies all hard constraints ("SampleSAT" or "SAMaxWalkSat")
verbose: whether to display results upon completion
details: whether to display information while the algorithm is running
infoInterval: [if details==True] interval (no. of steps) in which to display the current step number and some additional info
resultsInterval: [if details==True] interval (no. of steps) in which to display intermediate results; [if keepResultsHistory==True] interval in which to store intermediate results in the history
debug: whether to display debug information (e.g. internal data structures) while the algorithm is running
debugLevel: controls degree to which debug information is presented
keepResultsHistory: whether to store the history of results (at each resultsInterval)
referenceResults: reference results to compare obtained results to
saveHistoryFile: if not None, save history to given filename
sampleCallback: function that is called for every sample with the sample and step number as parameters
softEvidence: if None, use soft evidence from MLN, otherwise use given dictionary of soft evidence
handleSoftEvidence: if False, ignore all soft evidence in the MCMC sampling (but still compute softe evidence statistics if soft evidence is there)
'''
logger.debug("starting MC-SAT with maxsteps=%d, softevidence=%s" %
(self.maxsteps, self.softevidence))
# initialize the KB and gather required info
self._initkb()
# print CNF KB
logger.debug("CNF KB:")
for gf in self.gndformulas:
logger.debug("%7.3f %s" % (gf.weight, str(gf)))
print
# set the random seed if it was given
if self.rndseed is not None:
random.seed(self.rndseed)
# create chains
chaingroup = MCMCInference.ChainGroup(self)
self.chaingroup = chaingroup
for i in range(self.chains):
chain = MCMCInference.Chain(self, self.queries)
chaingroup.chain(chain)
# satisfy hard constraints using initialization algorithm
M = []
NLC = []
for i, gf in enumerate(self.gndformulas):
if gf.weight == HARD:
if gf.islogical():
clause_range = self.gf2clauseidx[i]
M.extend(range(*clause_range))
else:
NLC.append(gf)
if M or NLC:
logger.debug('Running SampleSAT')
chain.state = SampleSAT(
self.mrf, chain.state, M, NLC, self, p=self.p
).run(
) # Note: can't use p=1.0 because there is a chance of getting into an oscillating state
if logger.level == logs.DEBUG:
self.mrf.print_world_vars(chain.state)
self.step = 1
logger.debug('running MC-SAT with %d chains' % len(chaingroup.chains))
self._watch.tag('running MC-SAT', self.verbose)
if self.verbose:
bar = ProgressBar(steps=self.maxsteps, color='green')
while self.step <= self.maxsteps:
# take one step in each chain
for chain in chaingroup.chains:
# choose a subset of the satisfied formulas and sample a state that satisfies them
state = self._satisfy_subset(chain)
# update chain counts
chain.update(state)
if self.verbose:
bar.inc()
bar.label('%d / %d' % (self.step, self.maxsteps))
# intermediate results
self.step += 1
# get results
self.step -= 1
results = chaingroup.results()
return results[0]
def __init__(self, mrf, queries=ALL, **params):
MCMCInference.__init__(self, mrf, queries, **params)
self._weight_backup = list(self.mrf.mln.weights)
