一、使用步驟

1.引入庫（安裝Python環(huán)境、PyQt、PyQt-tools)

from PyQt5 import QtCore, QtGui, QtWidgetsimport sysimport datetimefrom PyQt5.QtGui import QStandardItemModel, QStandardItemfrom PyQt5.QtWidgets import QHeaderViewfrom collections import defaultdictimport numpy as np

2.全局變量

#text = 'E -> E + T nE -> TnT -> T * FnT -> FnF ->(E)nF -> i'#text = 'S -> BBnB -> aBnB -> b'my_dict = defaultdict(list)#記錄各個(gè)終結(jié)符的產(chǎn)生式my_dicts = defaultdict(list)#代表每組項(xiàng)目，暫時(shí)存儲(chǔ)VNT = []VT = set([])MAX = 50 #生成最多的項(xiàng)目集個(gè)數(shù)Inum = 0 #記錄項(xiàng)目集的個(gè)數(shù)end = [] #記錄，上一個(gè)狀態(tài)數(shù)，通過的字符，下一個(gè)狀態(tài)數(shù)[最終結(jié)果]numset = []#列表，修訂狀態(tài)數(shù) endstate = [] #最終存儲(chǔ)項(xiàng)目集鏃 [最終結(jié)果]guiyue = [] #記錄每條文法

3.完整代碼

# -*- 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, QtGui, QtWidgetsimport sysimport datetimefrom PyQt5.QtGui import QStandardItemModel, QStandardItemfrom PyQt5.QtWidgets import QHeaderViewfrom collections import defaultdictimport numpy as np#text = 'E -> E + T nE -> TnT -> T * FnT -> FnF ->(E)nF -> i'#text = 'S -> BBnB -> aBnB -> b'my_dict = defaultdict(list)#記錄各個(gè)終結(jié)符的產(chǎn)生式my_dicts = defaultdict(list)#代表每組項(xiàng)目，暫時(shí)存儲(chǔ)VNT = []VT = set([])MAX = 50 #生成最多的項(xiàng)目集個(gè)數(shù)Inum = 0 #記錄項(xiàng)目集的個(gè)數(shù)end = [] #記錄，上一個(gè)狀態(tài)數(shù)，通過的字符，下一個(gè)狀態(tài)數(shù)[最終結(jié)果]numset = []#列表，修訂狀態(tài)數(shù) endstate = [] #最終存儲(chǔ)項(xiàng)目集鏃 [最終結(jié)果]guiyue = [] #記錄每條文法def isTerminal(c): # 若c介于A-Z之間則認(rèn)為是非終結(jié)符(注意添加 self參數(shù)) if c < ’A’ or c > ’Z’: return True else: return Falsedef SplitText(text): # 把文法中E->A|B 切分為E->A和E->B mytext = '' for i in text: if(i != ’ ’):#刪除字符串的空格 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(xiàn)過的終結(jié)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(jì)算目標(biāo)字符串的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(jié)符的產(chǎn)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)#遞歸得到Frist集 if ’ε’ in Firstlist: # Firstlist其實(shí)是指一個(gè)listtime += 1 else: for vi in Firstlist:Zlist.append(vi) if(time == len(j)): Zlist.append(’ε’) return Zlistdef getSymbol(mystr):#根據(jù)Frist集得到下一個(gè)狀態(tài)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 #存儲(chǔ)展望符#print(getSymbol(’E->.E+T,#’))#驗(yàn)證展望符是否正確def CLOSURE(mystr,num): #用于項(xiàng)目集內(nèi)容的補(bǔ)充 my_dicts[num].append(mystr) #先加上它本身 zhanwang = getSymbol(mystr)#再計(jì)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: returndef deleteI(delnum): #刪除重復(fù)狀態(tài) for i in delnum: del my_dicts[i] def DFA(mynum): newstr = [] command = dict() global Inum for fs in my_dicts[mynum]: #用字典存儲(chǔ) 目標(biāo)字符和狀態(tài)集序號(hào) 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,len(fs)): if(fs[i]==’.’): if(fs[i+1]==’,’): break else: mynums = command[fs[i+1]] s1 = list(fs) s1[i] = s1[i+1] s1[i+1]=’.’ sq = ’’.join(s1) #巧妙實(shí)現(xiàn)字符串的替換 CLOSURE(sq,mynums) #生成新的狀態(tài)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(tài)序號(hào) delnum.append(value) #print(delnum) deleteI(delnum) for key,value in command.items(): #print(mynum,’(’,key,’)->’,value) end.append([mynum,key,value]) numset.append(mynum) numset.append(value) #利用集合特性，修訂狀態(tài)數(shù) 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, 770, 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, 10, 911, 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, 10, 911, 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, 10, 911, 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, 10, 51, 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 -> TnT -> T * FnT -> FnF ->(E)nF -> i') #初始化，編譯原理測(cè)試數(shù)據(jù) #self.textEdit.setText('S -> BBnB -> aBnB -> 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(cè)試數(shù)據(jù) self.label_3 = QtWidgets.QLabel(Form) self.label_3.setGeometry(QtCore.QRect(550, 200, 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) # 將按鈕與函數(shù)Runs()綁定,啟動(dòng)主程序 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), _translate('Form', '分 析 表')) self.tabWidget.setTabText(self.tabWidget.indexOf(self.Process), _translate('Form', '分 析 過 程')) self.tabWidget.setTabText(self.tabWidget.indexOf(self.States), _translate('Form', '項(xiàng) 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(yùn) 行 程 序')) def Runs(self): global VNT,VT,numset,Inum,endstate,guiyue,my_dict,my_dicts,end#初始化 Inum = 0 #記錄項(xiàng)目集的個(gè)數(shù) my_dict = defaultdict(list)#記錄各個(gè)終結(jié)符的產(chǎn)生式 my_dicts = defaultdict(list)#代表每組項(xiàng)目，暫時(shí)存儲(chǔ) VNT = [] VT = set([]) end = [] #記錄，上一個(gè)狀態(tài)數(shù)，通過的字符，下一個(gè)狀態(tài)數(shù) numset = []#列表，修訂狀態(tài)數(shù) [最終結(jié)果] endstate = [] #最終存儲(chǔ)項(xiàng)目集鏃 [最終結(jié)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(yùn) 行 時(shí) 間：’+times_str) text = self.textEdit.toPlainText() SplitText(text)#1 處理文法 input0 = text[0]+'’->.'+text[0]+’,#’ #輸入第一個(gè)項(xiàng)目 CLOSURE(input0,0) #2 生成I0項(xiàng)目集 for i in range(0,MAX): DFA(i) numset = list(set(numset))#3 消除重復(fù)元素 for i in end:#4 修訂狀態(tài)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 將修訂后的項(xiàng)目集族寫入新的列表 #將項(xiàng)目集族寫入圖形界面 self.textBrowser_3.setText('tttLR(1)項(xiàng) 目 集 族n') j = 0 for i in endstate: self.textBrowser_3.append(’I’+str(j)+’: ’+str(i)+’n’) j += 1 #將Frist集寫入圖形界面 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(gè)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(gòu)造分析表，寫入圖形界面 VT.discard(’#’) VT = list(VT) #先刪除# VT.append(’#’)#想讓#在ACTION表最后一列 label_x = [’狀 態(tài)’]+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))] #存儲(chǔ)分析表內(nèi)容，為分析過程做準(zhǔn)備 GOTO = [[’0’] * len(VNT) for i in range(len(endstate))] for q in end: #移進(jìn)動(dòng)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(jié)標(biāo)志 for i in range(len(endstate)):#規(guī)約動(dòng)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(jié)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(tài) stack = ’#’ #符 號(hào) inputstr = self.lineEdit.text()#輸 入 串 label_x = [’狀 態(tài)’, ’符 號(hào)’, ’輸 入 串’, ’動(dòng) 作’] self.model3.setHorizontalHeaderLabels(label_x) tabnum = 0 while(1): self.model3.setItem(tabnum,0,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(bào) 錯(cuò)！’) else: ch = ACTION[mystate[-1]][VT.index(inputstr[0])]#讀取action值 if(ch ==’r0’):#本質(zhì)就是acc self.textBrowser.setText(’分 析 成 功！’) break if(ch == ’0’): self.textBrowser.setText(’報(bào) 錯(cuò)！’) break if(ch[0] == ’s’): mystate.append(int(ch[1:]))#狀態(tài)加一個(gè) stack += inputstr[0]#移進(jìn) inputstr = inputstr[1:]#相當(dāng)于刪除第一個(gè)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(guī)約問題 gstack = gstack.replace(g1,g0,1) stack = gstack[::-1]#完成規(guī)約任務(wù) strlen = len(gylist[1]) #計(jì)算長(zhǎng)度 for i in range(strlen): mystate.pop()#連續(xù)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.運(yùn)行結(jié)果截圖

5.學(xué)會(huì)自己看注釋

6.用數(shù)據(jù)代碼，為我愛的世界添磚加瓦

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