def simplifyCFG(self, cfg):
""" Base Normal Form : epsilon-free Grammar """
self._loadCFG(cfg)
self._reduceCFG()
self._removeUnitProductins()
self._removeNullProductins()
return CFG().create(self._V, self._SIGMA, self._S, self._P)
def convertToNF(self, cfg):
ChomskyNF.convertToNF(self, cfg)
self._renameCFG()
self._orderProductions()
self._terminateFirstSymbol()
self._renameBackCFG()
return CFG().create(self._V, self._SIGMA, self._S, self._P)
def convertToNF(self, cfg):
self._loadCFG(cfg)
self._reduceCFG()
self._removeNullProductins()
self._replaceMixedTerminals()
self._splitNonTerminalSequences()
self._removeUnitProductins()
return CFG().create(self._V, self._SIGMA, self._S, self._P)
_v = {0: v}
for j in range(1, n):
if j != n - 1:
_v[j] = self._createVariable('X')
self._V.append(_v[j])
else:
_v[j] = p[j]
if _v[j] not in _P.keys():
_P[_v[j]] = []
_P[_v[j - 1]].append({0: p[j - 1], 1: _v[j]})
self._P = _P
if __name__ == "__main__":
print("Chomsky Normal Form")
G = CFG()
print('\nTest : check normal form (test/ChomskyNF.txt)')
G.loadFromFile('tests/ChomskyNF.txt')
result = ChomskyNF().isInNF(G)
print(G)
if result:
print('\ngrammar is in Chomsky normal form')
else:
print('\ngrammar is not in Chomsky normal form\n')
g = ChomskyNF().convertToNF(G)
print(g)
if ChomskyNF().isInNF(g):
print('\ngrammar is now in Chomsky normal form')
def _updateW(self, SET, _prev=None):
if _prev is not None:
W = [x for x in _prev]
else:
W = []
for v in self._P:
for p in self._P[v]:
for n, _v in p.items():
if _v in SET and v not in W:
W.append(v)
return W
if __name__ == "__main__":
G = CFG()
print('\nTest : reduce CFG (test/GenericNF_reduce.txt.txt)')
G.loadFromFile('tests/GenericNF_reduce.txt')
g = GenericNF().simplifyCFG(G.__copy__())
print(G, '\n', g)
print('\nTest : remove unit productins (tests/GenericNF_unit.txt)')
G.loadFromFile('tests/GenericNF_unit.txt')
g = GenericNF().simplifyCFG(G.__copy__())
print(G, '\n', g)
print('\nTest : remove null productins (tests/GenericNF_null.txt)')
G.loadFromFile('tests/GenericNF_null.txt')
g = GenericNF().simplifyCFG(G.__copy__())
print(G, '\n', g)
p0[len(p0)] = _v
_Ps[v] = [x for x in [p0] if x not in _Ps[v]] + _Ps[v]
p1 = {}
p2 = {}
for i, s in p.items():
if i != 0:
p1[i - 1] = s
p2[i - 1] = s
p2[len(p2)] = _v
_Ps[_v] = [x for x in [p1, p2] if x not in _Ps[_v]] + _Ps[_v]
return _Ps
if __name__ == "__main__":
print("Greibach Normal Form")
G = CFG()
print('\nTest : check normal form (tests/GreibachNF.txt)')
G.loadFromFile('tests/GreibachNF.txt')
result = GreibachNF().isInNF(G)
print(G)
if result:
print('\ngrammar is in Greibach normal form')
else:
print('\ngrammar is not in Greibach normal form\n')
g = GreibachNF().convertToNF(G)
print(
g.__str__([
'S', 'A', 'B', 'X\\_1', 'A\\_9', 'A\\_8', 'X\\_0', 'S\\_0',
'B\\_0', 'B\\_1'