67 lines
2.3 KiB
Python
67 lines
2.3 KiB
Python
S = [] # 以列表形式存储子句集S
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""" 读取子句集文件中子句，并存放在S列表中 - 每个子句也是以列表形式存储 - 以析取式分割 - 例如：～p ∨ ～q ∨ r 存储形式为 ['～p', '～q', 'r'] """
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def readClauseSet(filePath):
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# global S
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for line in open(filePath, mode='r', encoding='utf-8'):
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line = line.replace(' ', '').strip()
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line = line.split('∨')
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S.append(line)
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print(S)
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""" - 为正文字，则返回其负文字 - 为负文字，则返回其正文字 """
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def opposite(clause):
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if '～' in clause:
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return clause.replace('～', '')
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else:
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return '～' + clause
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""" 归结 """
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def resolution():
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# global S
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end = False
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while True:
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if end: break
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father = S.pop()
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print('father:',father)
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for i in father[:]:
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if end: break
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for mother in S[:]:
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print('mother:',mother)
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if end: break
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j = list(filter(lambda x: x == opposite(i), mother))
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if j==[]:
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continue
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else:
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print('\n亲本子句：' + ' ∨ '.join(father) + ' 和 ' + ' ∨ '.join(mother))
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father.remove(i)
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mother.remove(j[0])
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print(father,mother)
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#********** Begin **********#
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if father==[] and mother==[]:
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print('归结式：NIL')
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end = True
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elif father==[]:
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print('归结式：' + ' ∨ '.join(mother))
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elif mother==[]:
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print('归结式：' + ' ∨ '.join(father))
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else:
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new_clause = father + mother # 创建新的归结式
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print('归结式：' + ' ∨ '.join(new_clause))
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S.append(new_clause) # 将新的归结式添加到 S 中
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print('S:',S)
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#********** End **********#
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def main():
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filePath = r'命题逻辑归结推理系统S.txt'
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readClauseSet(filePath)
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resolution()
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if __name__ == '__main__':
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main() |