一、使用步驟

1.引入庫（安裝Python環境、PyQt、PyQt-tools)

from PyQt5 import QtCore,QtGui,QtWidgets
import sys
import datetime
from PyQt5.QtGui import QStandardItemModel,QStandardItem
from PyQt5.QtWidgets import QHeaderView
from collections import defaultdict
import numpy as np

2.全域性變數

#text = "E -> E + T \nE -> T\nT -> T * F\nT -> F\nF ->(E)\nF -> i"
#text = "S -> BB\nB -> aB\nB -> b"
my_dict = defaultdict(list)#記錄各個終結符的產生式
my_dicts = defaultdict(list)#代表每組專案，暫時儲存
VNT = []
VT = set([])
MAX = 50 #生成最多的專案集個數
Inum = 0 #記錄專案集的個數
end = [] #記錄，上一個狀態數，通過的字元，下一個狀態數[最終結果]
numset = []#列表，修訂狀態數 
endstate = [] #最終儲存專案集鏃 [最終結果]
guiyue = [] #記錄每條文法

3.完整程式碼

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'LR1.ui'
#
# Created by: PyQt5 UI code generator 5.15.1
#
# WARNING: Any manual changes made to this file will be lost when pyuic5 is
# run again. Do not edit this file unless you know what you are doing.


from PyQt5 import QtCore,QStandardItem
from PyQt5.QtWidgets import QHeaderView
from collections import defaultdict
import numpy as np
#text = "E -> E + T \nE -> T\nT -> T * F\nT -> F\nF ->(E)\nF -> i"
#text = "S -> BB\nB -> aB\nB -> b"
my_dict = defaultdict(list)#記錄各個終結符的產生式
my_dicts = defaultdict(list)#代表每組專案，暫時儲存
VNT = []
VT = set([])
MAX = 50 #生成最多的專案集個數
Inum = 0 #記錄專案集的個數
end = [] #記錄，上一個狀態數，通過的字元，下一個狀態數[最終結果]
numset = []#列表，修訂狀態數 
endstate = [] #最終儲存專案集鏃 [最終結果]
guiyue = [] #記錄每條文法
def isTerminal(c): # 若c介於A-Z之間則認為是非終結符(注意新增 self引數)
  if c < 'A' or c > 'Z':
   return True
  else:
   return False
def SplitText(text): # 把文法中E->A|B 切分為E->A和E->B
 mytext = ""
 for i in text:
  if(i != ' '):#刪除字串的空格
   mytext += i;
 i = mytext.split('\n')
 guiyue.append(text[0]+"'->"+text[0])
 for j in i:
  if(VNT.count(j[0])==0):#沒出現過的終結符
   VNT.append(j[0]) 
  for k in range(1,len(j)):
   if(j[k]=='-' and j[k+1]=='>'):
    k = k+2
    break
  guiyue.append(j)
  my_dict[j[0]].append(j[k:])
def getFirst(mylist):#計算目標字串的Frist集
 Zlist = []
 for i in mylist:
  if(i not in VNT):
   Zlist.append(i)
   return Zlist
  else:
   for j in my_dict[i]: #遍歷非終結符的產生式
    #print(j)
    if(j[0] == i):
     continue
    time = 0
    for ch in j:
     if(ch not in VNT):
      Zlist.append(ch)
      break
     else:
      Firstlist = getFirst(ch)#遞迴得到Frist集
      if 'ε' in Firstlist: # Firstlist其實是指一個list
        time += 1
      else:
       for vi in Firstlist:
        Zlist.append(vi)
    if(time == len(j)):
     Zlist.append('ε')
   return Zlist

def getSymbol(mystr):#根據Frist集得到下一個狀態的展望符
 for i in range(0,len(mystr)):
  if(mystr[i] =='.'):
   mylist = list(mystr[i+2:])
   break
 Zlist = ['#']
 if(mylist[0]==','):
  mylist = mylist[1:]
 if(mylist[0]=='#'):
  VT.add('#')
  return Zlist
 a = getFirst(mylist)
 VT.update(set(a))
 return a #儲存展望符
#print(getSymbol('E->.E+T,#'))#驗證展望符是否正確

def CLOSURE(mystr,num): #用於專案集內容的補充
 my_dicts[num].append(mystr) #先加上它本身
 zhanwang = getSymbol(mystr)#再計算展望符
 for i in range(0,len(mystr)):
  if(mystr[i] =='.'):
   ch = mystr[i+1]
 if(ch in VNT):
  for j in range(0,len(my_dict[ch])):
   ch2 = my_dict[ch][j]
   for k in range(0,len(zhanwang)):
    mystr = ch+"->."+ch2+","+zhanwang[k]
    if(my_dicts[num].count(mystr)==0):
     my_dicts[num].append(mystr)
    if(ch2[0] in VNT):
     for ss in my_dict[ch2[0]]:
      zhanwangs = getSymbol(mystr)
      for kk in range(0,len(zhanwangs)):
       mystr2 = ch2[0]+"->."+ss+","+zhanwangs[kk]
       if(my_dicts[num].count(mystr2)==0):
        CLOSURE(mystr2,num)
   
 else:
  return
def deleteI(delnum): #刪除重複狀態
 for i in delnum:
  del my_dicts[i]
 
def DFA(mynum):
 newstr = [] 
 command = dict()
 global Inum
 for fs in my_dicts[mynum]: #用字典儲存 目標字元和狀態集序號
  for i in range(0,len(fs)):
   if(fs[i]=='.'):
    if(fs[i+1]==','):
     break
    else:
     if(newstr.count(fs[i+1])==0):
      newstr.append(fs[i+1])
      Inum += 1
      command[fs[i+1]] = Inum   
 for fs in my_dicts[mynum]:
  for i in range(0,'):
     break
    else:
     mynums = command[fs[i+1]]
     s1 = list(fs)
     s1[i] = s1[i+1]
     s1[i+1]='.'
     sq = ''.join(s1) #巧妙實現字串的替換
     CLOSURE(sq,mynums) #生成新的狀態集
 #print(command)
 delnum = []
 for key,value in command.items():
  for j in range(0,value):
   if(set(my_dicts[j]) == set(my_dicts[value])):
    command[key] = j #修改狀態序號
    delnum.append(value)
 #print(delnum)
 deleteI(delnum)
 for key,value in command.items():
  #print(mynum,'(',key,')->',value)
  end.append([mynum,value])
  numset.append(mynum)
  numset.append(value) #利用集合特性，修訂狀態數     

class Ui_Form(object):
 def setupUi(self,Form):
  Form.setObjectName("Form")
  Form.resize(994,824)
  self.textBrowser = QtWidgets.QTextBrowser(Form)
  self.textBrowser.setGeometry(QtCore.QRect(520,770,461,51))
  self.textBrowser.setObjectName("textBrowser")
  self.textBrowser_2 = QtWidgets.QTextBrowser(Form)
  self.textBrowser_2.setGeometry(QtCore.QRect(25,771,421,41))
  self.textBrowser_2.setObjectName("textBrowser_2")
  self.label = QtWidgets.QLabel(Form)
  self.label.setGeometry(QtCore.QRect(460,51,41))
  self.label.setObjectName("label")
  self.tabWidget = QtWidgets.QTabWidget(Form)
  self.tabWidget.setGeometry(QtCore.QRect(20,240,941,521))
  self.tabWidget.setObjectName("tabWidget")
  self.First = QtWidgets.QWidget()
  self.First.setAccessibleName("")
  self.First.setObjectName("First")
  self.tableView = QtWidgets.QTableView(self.First)
  self.tableView.setGeometry(QtCore.QRect(10,10,911,471))
  self.tableView.setObjectName("tableView")
  self.tabWidget.addTab(self.First,"")
  self.Analyse = QtWidgets.QWidget()
  self.Analyse.setObjectName("Analyse")
  self.tableView_2 = QtWidgets.QTableView(self.Analyse)
  self.tableView_2.setGeometry(QtCore.QRect(10,471))
  self.tableView_2.setObjectName("tableView_2")
  self.tabWidget.addTab(self.Analyse,"")
  self.Process = QtWidgets.QWidget()
  self.Process.setObjectName("Process")
  self.tableView_3 = QtWidgets.QTableView(self.Process)
  self.tableView_3.setGeometry(QtCore.QRect(10,471))
  self.tableView_3.setObjectName("tableView_3")
  self.tabWidget.addTab(self.Process,"")
  self.States = QtWidgets.QWidget()
  self.States.setObjectName("States")
  self.textBrowser_3 = QtWidgets.QTextBrowser(self.States)
  self.textBrowser_3.setGeometry(QtCore.QRect(10,471))
  self.textBrowser_3.setObjectName("textBrowser_3")
  self.tabWidget.addTab(self.States,"")
  self.label_2 = QtWidgets.QLabel(Form)
  self.label_2.setGeometry(QtCore.QRect(40,41))
  self.label_2.setObjectName("label_2")
  self.textEdit = QtWidgets.QTextEdit(Form)
  self.textEdit.setGeometry(QtCore.QRect(33,46,441,181))
  self.textEdit.setObjectName("textEdit")
  self.textEdit.setText("E -> E + T \nE -> T\nT -> T * F\nT -> F\nF ->(E)\nF -> i")
 #初始化，編譯原理測試資料
  #self.textEdit.setText("S -> BB\nB -> aB\nB -> b")
  self.lineEdit = QtWidgets.QLineEdit(Form)
  self.lineEdit.setGeometry(QtCore.QRect(640,200,271,41))
  self.lineEdit.setObjectName("lineEdit")
  self.lineEdit.setText("i*i+i#")
 #初始化，編譯原理測試資料
  self.label_3 = QtWidgets.QLabel(Form)
  self.label_3.setGeometry(QtCore.QRect(550,81,41))
  self.label_3.setObjectName("label_3")
  self.pushButton = QtWidgets.QPushButton(Form)
  self.pushButton.setGeometry(QtCore.QRect(650,110,251,71))
  self.pushButton.setObjectName("pushButton")
  self.pushButton.clicked.connect(self.Runs) # 將按鈕與函式Runs()繫結,啟動主程式
  self.retranslateUi(Form)
  self.tabWidget.setCurrentIndex(0)
  QtCore.QMetaObject.connectSlotsByName(Form)

 def retranslateUi(self,Form):
  _translate = QtCore.QCoreApplication.translate
  Form.setWindowTitle(_translate("Form","LR(1)文法"))
  self.label.setText(_translate("Form","分 析："))
  self.tabWidget.setTabText(self.tabWidget.indexOf(self.First),_translate("Form","FIRST集"))
  self.tabWidget.setTabText(self.tabWidget.indexOf(self.Analyse),"分 析 表"))
  self.tabWidget.setTabText(self.tabWidget.indexOf(self.Process),"分 析 過 程"))
  self.tabWidget.setTabText(self.tabWidget.indexOf(self.States),"項 目 集 族"))
  self.label_2.setText(_translate("Form","文 法："))
  self.label_3.setText(_translate("Form","輸 入 框"))
  self.pushButton.setText(_translate("Form","運 行 程 序"))
 def Runs(self):
  global VNT,VT,numset,Inum,endstate,guiyue,my_dict,my_dicts,end#初始化
  Inum = 0 #記錄專案集的個數
  my_dict = defaultdict(list)#記錄各個終結符的產生式
  my_dicts = defaultdict(list)#代表每組專案，暫時儲存
  VNT = []
  VT = set([])
  end = [] #記錄，上一個狀態數，通過的字元，下一個狀態數
  numset = []#列表，修訂狀態數 [最終結果]
  endstate = [] #最終儲存專案集鏃 [最終結果]
  guiyue = [] #記錄每條文法
  times = datetime.datetime.now()
  times_str = times.strftime('  %Y-%m-%d %H:%M:%S')
  self.textBrowser_2.setText('運 行 時 間：'+times_str)
  text = self.textEdit.toPlainText()
  SplitText(text)#1 處理文法
  input0 = text[0]+"'->."+text[0]+',#' #輸入第一個專案
  CLOSURE(input0,0) #2 生成I0專案集
  for i in range(0,MAX):
   DFA(i)
  numset = list(set(numset))#3 消除重複元素
  for i in end:#4 修訂狀態過程
   i[0] = numset.index(i[0])
   i[2] = numset.index(i[2])
  for i in range(0,len(my_dicts)):
   if my_dicts[i] != []:
    endstate.append(my_dicts[i])#5 將修訂後的專案集族寫入新的列表
  #將專案集族寫入圖形介面
  self.textBrowser_3.setText("\t\t\tLR(1)項 目 集 族\n")
  j = 0
  for i in endstate:
   self.textBrowser_3.append('I'+str(j)+': '+str(i)+'\n')
   j += 1
  #將Frist集寫入圖形介面
  self.model = QStandardItemModel(len(VNT),5)
  label_y = []
  for s in VNT:
   label_y.append(s)
  self.model.setVerticalHeaderLabels(label_y)
  for row in range(len(VNT)):
    flist = [VNT[row]]#First集要輸入一個列表
    Flist = list(set(getFirst(flist)))
    for column in range(len(Flist)):
     item = QStandardItem(Flist[column])
     self.model.setItem(row,column,item)
  self.tableView.horizontalHeader().setStretchLastSection(True)
  self.tableView.horizontalHeader().setSectionResizeMode(QHeaderView.Stretch)
  self.tableView.setModel(self.model)
  #構造分析表，寫入圖形介面
  VT.discard('#')
  VT = list(VT) #先刪除#
  VT.append('#')#想讓#在ACTION表最後一列
  label_x = ['狀 態']+VT+VNT
  self.model2 = QStandardItemModel(len(endstate),len(VNT)+len(VT))
  self.model2.setHorizontalHeaderLabels(label_x)
  label_y = []
  for i in range(0,len(endstate)):
   label_y.append(str(i))
  self.model2.setVerticalHeaderLabels(label_y)
  ACTION = [['0'] * len(VT) for i in range(len(endstate))] #儲存分析表內容，為分析過程做準備
  GOTO = [['0'] * len(VNT) for i in range(len(endstate))]
  for q in end: #移進動作
   if(q[1] not in VNT):
    ss = 's'+str(q[2])
    ACTION[int(q[0])][VT.index(q[1])] = ss
   else:
    ss = str(q[2])
    GOTO[int(q[0])][VNT.index(q[1])] = ss
   item = QStandardItem(ss)
   self.model2.setItem(int(q[0]),label_x.index(q[1]),item)
  endstr = text[0]+"'->"+text[0]+'.,#' #終結標誌
  for i in range(len(endstate)):#規約動作
   for j in range(len(endstate[i])):
    for k in range(len(endstate[i][j])):
     if(endstate[i][j][k]=='.'):
      if(endstate[i][j][k+1]== ','):
       #print(guiyue)
       ii = guiyue.index(endstate[i][j][:k])
       item = QStandardItem("r"+str(ii))
       ACTION[i][VT.index(endstate[i][j][k+2])] = "r"+str(ii)
       self.model2.setItem(i,label_x.index(endstate[i][j][k+2]),item)
   if(endstate[i][0] == endstr):
    item = QStandardItem("acc")#結束
    self.model2.setItem(i,label_x.index('#'),item)    
  self.tableView_2.horizontalHeader().setStretchLastSection(True)
  self.tableView_2.horizontalHeader().setSectionResizeMode(QHeaderView.Stretch)
  self.tableView_2.setModel(self.model2)
  self.model3 = QStandardItemModel(32,4)
  #print(ACTION)
  #print(GOTO)
  mystate = [0]#狀 態
  stack = '#' #符 號
  inputstr = self.lineEdit.text()#輸 入 串
  label_x = ['狀 態','符 號','輸 入 串','動 作']
  self.model3.setHorizontalHeaderLabels(label_x)
  tabnum = 0
  while(1):
   self.model3.setItem(tabnum,QStandardItem(str(mystate)))
   self.model3.setItem(tabnum,1,QStandardItem(stack))
   self.model3.setItem(tabnum,2,QStandardItem(inputstr))
   tabnum += 1
   if(inputstr[0] not in VT):
    self.textBrowser.setText('報 錯！')
   else:
    ch = ACTION[mystate[-1]][VT.index(inputstr[0])]#讀取action值
   if(ch =='r0'):#本質就是acc
    self.textBrowser.setText('分 析 成 功！')
    break
   if(ch == '0'):
    self.textBrowser.setText('報 錯！')
    break
   if(ch[0] == 's'):
    mystate.append(int(ch[1:]))#狀態加一個
    stack += inputstr[0]#移進
    inputstr = inputstr[1:]#相當於刪除第一個元素
   if(ch[0] == 'r'):
    gylist = guiyue[int(ch[1:])].split('->')
    g1 = str(gylist[1])[::-1]
    g0 = str(gylist[0])[::-1]
    gstack = stack[::-1]#逆序解決規約問題
    gstack = gstack.replace(g1,g0,1)
    stack = gstack[::-1]#完成規約任務
    strlen = len(gylist[1]) #計算長度
    for i in range(strlen):
     mystate.pop()#連續出棧
    mystate.append(int(GOTO [mystate[-1]] [VNT.index(gylist[0])] ))
  self.tableView_3.horizontalHeader().setStretchLastSection(True)
  self.tableView_3.horizontalHeader().setSectionResizeMode(QHeaderView.Stretch)
  self.tableView_3.setModel(self.model3)
if __name__ == "__main__":
 app = QtWidgets.QApplication(sys.argv)
 Form = QtWidgets.QWidget()
 ui = Ui_Form()
 ui.setupUi(Form)
 Form.show()
 sys.exit(app.exec_())

4.執行結果截圖

5.學會自己看註釋

6.用資料程式碼，為我愛的世界添磚加瓦

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