python正则表达式之作业计算器

#!/usr/bin/env python3#antuor:Alan import refrom functools import reducefrom tkinter import *   '''处理特殊－号运算'''def minus_operation(expresstion):  minus_operators = re.split("-",expresstion)  calc_list = re.findall("[0-9]",expresstion)  if minus_operators[0] =="":    calc_list[0] = '-%s' % calc_list[0]  res = reduce(lambda x,y:float(x)-float(y),calc_list)  print(">>>>>>>>>>>>>>减号[%s]运算结果:" % expresstion,res)  return res '''reduce()对sequence连续使用function, 如果不给出initial, 则第一次调用传递sequence的两个元素,以后把前一次调用的结果和sequence的下一个元素传递给function'''    '''处理双运算符号'''def del_duplicates(expresstion):  expresstion = expresstion.replace("++","+")  expresstion = expresstion.replace("--","-")  expresstion = expresstion.replace("+-","-")  expresstion = expresstion.replace("--","+")  expresstion = expresstion.replace('- -',"+")  e  return expresstion '''＊／运算函数'''def mutiply_dividend(expresstion):  calc_list = re.split("[*/]",expresstion)     #用＊ or /分割公式  operators = re.findall("[*/]",expresstion)    #找出所有＊和／号  res = None  for index,i in enumerate(calc_list):    if res:      if operators[index-1] =='*':        res *= float(i)      elif operators[index-1] =='/':        res /=float(i)    else :      res = float(i)  procession0 = "[%s]运算结果=" % expresstion,res  final_result.insert(END,procession0)    #插入窗体  print(procession0)  return res   '''处理运算符号顺序混乱情况'''def special_features(plus_and_minus_operators,multiply_and_dividend):   for index,i in enumerate(multiply_and_dividend):    i = i.strip()    if i.endswith("*") or i.endswith("/"):      multiply_and_dividend[index] = multiply_and_dividend[index] + plus_and_minus_operators[index] + multiply_and_dividend[index+1]      del multiply_and_dividend[index+1]      del plus_and_minus_operators[index]  return plus_and_minus_operators,multiply_and_dividend   def minus_special(operator_list,calc_list):  for index,i in enumerate(calc_list):    if i =='':      calc_list[index+1] = i + calc_list[index+1].strip()   '''运算除了（）的公式＋－＊／'''def figure_up(expresstion):  expresstion = expresstion.strip("()")    #去掉外面括号  expresstion = del_duplicates(expresstion)  #去掉重复＋－号  plus_and_minus_operators = re.findall("[+-]",expresstion)  multiply_and_dividend = re.split("[+-]",expresstion)  if len(multiply_and_dividend[0].strip()) ==0:    multiply_and_dividend[1] = plus_and_minus_operators[0] + multiply_and_dividend[1]    del multiply_and_dividend[0]    del plus_and_minus_operators[0]   plus_and_minus_operators,multiply_and_dividend = special_features(plus_and_minus_operators,multiply_and_dividend)  for index,i in enumerate(multiply_and_dividend):    if re.search("[*/]",i):      sub_res = mutiply_dividend(i)      multiply_and_dividend[index] = sub_res   print(multiply_and_dividend,plus_and_minus_operators)  #计算  final_res = None  for index,item in enumerate(multiply_and_dividend):    if final_res:      if plus_and_minus_operators[index-1] == '+':        final_res += float(item)      elif plus_and_minus_operators[index-1] == '-':        final_res -= float(item)    else:      final_res = float(item)  procession = '[%s]计算结果:' % expresstion,final_res  final_result.insert(END,procession)    #插入窗体  print(procession)  return final_res """主函数：运算逻辑：先计算拓号里的值,算出来后再算乘除,再算加减"""def calculate():  expresstion = expresstions.get()         #获取输入框值  flage = True  calculate_res = None               #初始化计算结果为None  while flage:    m = re.search("/([^()]*/)",expresstion)    #先找最里层的（）    # pattern = re.compile(r"/([^()]*/)")    # m = pattern.match(expresstion)    if m:      sub_res = figure_up(m.group())      #运算（）里的公式      expresstion = expresstion.replace(m.group(),str(sub_res))  #运算完毕把结果替换掉公式    else:      print('---------------括号已经计算完毕--------------')      procession1 = "最终计算结果:",figure_up(expresstion)      final_result.insert(END,procession1)   #插入窗体      print('/033[31m最终计算结果:',figure_up(expresstion))       flage = False  if __name__=="__main__":  # res = calculate("1 - 2 * ( (60-30 +(-40/5) * (9-2*5/3 + 7 /3*99/4*2998 +10 * 568/14 )) - (-4*3)/ (16-3*2) )")  window = Tk()         ###创建窗体  window.title('计算器')    ###命名窗体  frame1 = Frame(window)    ###框架1  frame1.pack()        ###放置  frame2 = Frame(window)    ###框架2  frame2.pack()        ###放置  lable = Label(frame1,text = "请输入公式：")  ###文字标签  lable.pack()  expresstions = StringVar()  ###输入框属性，字符串  entryname = Entry(frame1,textvariable = expresstions) ###文本输入框  bt_get_expresstions = Button(frame1,text = "提交",command = calculate) ###按钮挂件  bt_get_expresstions.pack()  entryname.pack()  lable.grid(row =1,column =1)  ###位置  entryname.grid(row=1,column =2)  bt_get_expresstions.grid(row =1,column =3)  final_result = Text(frame2)  ###计算结果显示框  final_result.tag_config("here", background="yellow", foreground="blue")  final_result.pack()  window.mainloop()       ###事件循环