def neg(p):
if dlvhex.learnSupportSets():
dlvhex.learn((
dlvhex.storeAtom((p, )).negate(), # if p is true
dlvhex.storeOutputAtom(()).negate() # then () is in the output
));
else:
for x in dlvhex.getTrueInputAtoms():
return
dlvhex.output(())
def id(p): if dlvhex.learnSupportSets(): dlvhex.learn(( dlvhex.storeAtom((p, )), # if p is true for some X dlvhex.storeOutputAtom(()).negate() # then () is in the output )); else: for x in dlvhex.getTrueInputAtoms(): dlvhex.output(()) return
def parity(p):
if dlvhex.learnSupportSets():
pos = ()
for x in dlvhex.getInputAtoms():
pos = pos + (False, )
# special case: no input
if pos == ():
# always true
dlvhex.learn(dlvhex.storeOutputAtom(()).negate(), )
else:
pos = pos[:-1]
pos = list(pos)
overflow = False
while not overflow:
ng = ()
# enumerate all combinations except for the last element (which is then definite)
last = False
for i in range(0, len(pos)):
if pos[i] == True:
ng = ng + (dlvhex.getInputAtoms()[i], )
last = not last
else:
ng = ng + (dlvhex.getInputAtoms()[i].negate(), )
# add last element with a sign such that the partiy is even
if last:
ng = ng + (dlvhex.getInputAtoms()[-1], )
else:
ng = ng + (dlvhex.getInputAtoms()[-1].negate(), )
# generate nogood which implies that the external atom is true
supset = ng + (dlvhex.storeOutputAtom(()).negate(), )
dlvhex.learn(supset)
# go to next combination and check if we have an overflow, i.e., all combinations have been enumerated
inc=0
pos[inc] = not pos[inc]
while not overflow and not pos[inc]:
inc = inc + 1
if inc >= len(pos):
overflow = True
else:
pos[inc] = not pos[inc]
even = True
for atom in dlvhex.getInputAtoms():
if atom.isTrue():
even = not even
if even:
dlvhex.output(())
def parity(p):
if dlvhex.learnSupportSets():
pos = ()
for x in dlvhex.getInputAtoms():
pos = pos + (False, )
# special case: no input
if pos == ():
# always true
dlvhex.learn(dlvhex.storeOutputAtom(()).negate(), )
else:
pos = pos[:-1]
pos = list(pos)
overflow = False
while not overflow:
ng = ()
# enumerate all combinations except for the last element (which is then definite)
last = False
for i in range(0, len(pos)):
if pos[i] == True:
ng = ng + (dlvhex.getInputAtoms()[i], )
last = not last
else:
ng = ng + (dlvhex.getInputAtoms()[i].negate(), )
# add last element with a sign such that the partiy is even
if last:
ng = ng + (dlvhex.getInputAtoms()[-1], )
else:
ng = ng + (dlvhex.getInputAtoms()[-1].negate(), )
# generate nogood which implies that the external atom is true
supset = ng + (dlvhex.storeOutputAtom(()).negate(), )
dlvhex.learn(supset)
# go to next combination and check if we have an overflow, i.e., all combinations have been enumerated
inc=0
pos[inc] = not pos[inc]
while not overflow and not pos[inc]:
inc = inc + 1
if inc >= len(pos):
overflow = True
else:
pos[inc] = not pos[inc]
even = True
for atom in dlvhex.getInputAtoms():
if atom.isTrue():
even = not even
if even:
dlvhex.output(())
def aOrNotB(a,b): if dlvhex.learnSupportSets(): dlvhex.learn(( dlvhex.storeAtom((a, )), dlvhex.storeOutputAtom(()).negate() # then () is in the output )); dlvhex.learn(( dlvhex.storeAtom((b, )).negate(), dlvhex.storeOutputAtom(()).negate() # then () is in the output )); else: aIsTrue = dlvhex.isTrue(dlvhex.storeAtom((a, ))) bIsFalse = dlvhex.isFalse(dlvhex.storeAtom((b, ))) if aIsTrue or bIsFalse: dlvhex.output(())
def aOrNotB(a,b): if dlvhex.learnSupportSets(): dlvhex.learn(( dlvhex.storeAtom((a, )), dlvhex.storeOutputAtom(()).negate() # then () is in the output )); dlvhex.learn(( dlvhex.storeAtom((b, )).negate(), dlvhex.storeOutputAtom(()).negate() # then () is in the output )); else: aIsTrue = dlvhex.isTrue(dlvhex.storeAtom((a, ))) bIsFalse = dlvhex.isFalse(dlvhex.storeAtom((b, ))) if aIsTrue or bIsFalse: dlvhex.output(())
