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')