计算器开发需求
- 实现加减乘除及拓号优先级解析
- 用户输入 1 - 2 * ( (60-30 +(-40/5) * (9-2*5/3 + 7 /3*99/4*2998 +10 * 568/14 )) - (-4*3)/ (16-3*2) )等类似公式后，必须自己解析里面的(),+,-,*,/符号和公式，运算后得出结果，结果必须与真实的计算器所得出的结果一致
简单计算器1 import re 2 import functools 3 4 5 def minus_operator_handler(formula): 6 '''处理一些特殊的减号运算''' 7 minus_operators = re.split("-", formula) 8 calc_list = re.findall("[0-9]", formula) 9 if minus_operators[0] == '': # 第一值肯定是负号 10 calc_list[0] = '-%s' % calc_list[0] 11 res = functools.reduce(lambda x, y: float(x) - float(y), calc_list) 12 print("减号[%s]处理结果:" % formula, res) 13 return res 14 15 16 def remove_duplicates(formula): 17 formula = formula.replace("++", "+") 18 formula = formula.replace("+-", "-") 19 formula = formula.replace("-+", "-") 20 formula = formula.replace("--", "+") 21 formula = formula.replace("- -", "+") 22 return formula 23 24 25 def compute_mutiply_and_dividend(formula): 26 '''算乘除,传进来的是字符串噢''' 27 operators = re.findall("[*/]", formula) 28 calc_list = re.split("[*/]", formula) 29 res = None 30 for index, i in enumerate(calc_list): 31 if res: 32 if operators[index - 1] == "*": 33 res *= float(i) 34 elif operators[index - 1] == "/": 35 res /= float(i) 36 else: 37 res = float(i) 38 39 print("[%s]运算结果=" % formula, res) 40 return res 41 42 43 def handle_minus_in_list(operator_list, calc_list): 44 '''有的时候把算术符和值分开后,会出现这种情况 ['-', '-', '-'] [' ', '14969037.996825399 ', ' ', '12.0/ 10.0 '] 45 这需要把第2个列表中的空格都变成负号并与其后面的值拼起来,恶心死了 46 ''' 47 for index, i in enumerate(calc_list): 48 if i == '': # 它其实是代表负号,改成负号 49 calc_list[index + 1] = i + calc_list[index + 1].strip() 50 51 52 def handle_special_occactions(plus_and_minus_operators, multiply_and_dividend): 53 '''有时会出现这种情况 , ['-', '-'] ['1 ', ' 2 * ', '14969036.7968254'],2*...后面这段实际是 2*-14969036.7968254,需要特别处理下,太恶心了''' 54 for index, i in enumerate(multiply_and_dividend): 55 i = i.strip() 56 if i.endswith("*") or i.endswith("/"): 57 multiply_and_dividend[index] = multiply_and_dividend[index] + plus_and_minus_operators[index] + 58 multiply_and_dividend[index + 1] 59 del multiply_and_dividend[index + 1] 60 del plus_and_minus_operators[index] 61 return plus_and_minus_operators, multiply_and_dividend 62 63 64 def compute(formula): 65 '''这里计算是的不带括号的公式''' 66 67 formula = formula.strip("()") # 去除外面包的拓号 68 formula = remove_duplicates(formula) # 去除外重复的+-号 69 plus_and_minus_operators = re.findall("[+-]", formula) 70 multiply_and_dividend = re.split("[+-]", formula) # 取出乘除公式 71 if len(multiply_and_dividend[0].strip()) == 0: # 代表这肯定是个减号 72 multiply_and_dividend[1] = plus_and_minus_operators[0] + multiply_and_dividend[1] 73 del multiply_and_dividend[0] 74 del plus_and_minus_operators[0] 75 76 plus_and_minus_operators, multiply_and_dividend = handle_special_occactions(plus_and_minus_operators, 77 multiply_and_dividend) 78 for index, i in enumerate(multiply_and_dividend): 79 if re.search("[*/]", i): 80 sub_res = compute_mutiply_and_dividend(i) 81 multiply_and_dividend[index] = sub_res 82 83 # 开始运算+,- 84 print(multiply_and_dividend, plus_and_minus_operators) 85 total_res = None 86 for index, item in enumerate(multiply_and_dividend): 87 if total_res: # 代表不是第一次循环 88 if plus_and_minus_operators[index - 1] == '+': 89 total_res += float(item) 90 elif plus_and_minus_operators[index - 1] == '-': 91 total_res -= float(item) 92 else: 93 total_res = float(item) 94 print("[%s]运算结果:" % formula, total_res) 95 return total_res 96 97 98 def calc(formula): 99 '''计算程序主入口, 主要逻辑是先计算拓号里的值,算出来后再算乘除,再算加减''' 100 parenthesise_flag = True 101 calc_res = None # 初始化运算结果为None,还没开始运算呢,当然为None啦 102 while parenthesise_flag: 103 m = re.search("([^()]*)", formula) # 找到最里层的拓号 104 if m: 105 # print("先算拓号里的值:",m.group()) 106 sub_res = compute(m.group()) 107 formula = formula.replace(m.group(), str(sub_res)) 108 else: 109 print('……没括号了……') 110 111 print(' 最终结果:', compute(formula)) 112 parenthesise_flag = False # 代表公式里的拓号已经都被剥除啦 113 114 115 if __name__ == '__main__': 116 # res = calc("1 - 2 * ( (60-30 +(-40/5) * (9-2*5/3 + 7 /3*99/4*2998 +10 * 568/14 )) - (-4*3)/ (16-3*2) )") 117 res = calc( 118 "1 - 2 * ( (60-30 +(-9-2-5-2*3-5/3-40*4/2-3/5+6*3) * (-9-2-5-2*5/3 + 7 /3*99/4*2998 +10 * 568/14 )) - (-4*3)/ (16-3*2) )")
窗口计算器import re from functools import reduce from 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('- -', "+") 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:%s "%figure_up(expresstion) print(procession1) final_result.insert(END, procession1) # 插入窗体 # print(' 33[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_slaves(row=1,column=1) entryname.grid_slaves(row=1,column=1) bt_get_expresstions.grid_slaves(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
精简版计算器import re def math(dic): x, y = float(dic['x']), float(dic['y']) if dic['mark'] == '+': return x + y elif dic['mark'] == '-': return x - y elif dic['mark'] == '*': return x * y else: return x / y def suansu(re_str): ret4 = re.search(r'(?P<x>d+.?d*)(?P<mark>[*/])(?P<y>[-]?d+.?d*)', re_str) try: while ret4.group(): re_str = re_str.replace(ret4.group(), str(math(ret4.groupdict()))) if '--' in re_str: re_str = re_str.replace('--', '+') if '++' in re_str: re_str = re_str.replace('++', '+') ret4 = re.search(r'(?P<x>[-]?d+.?d*)(?P<mark>[*/])(?P<y>[-]?d+.?d*)', re_str) except AttributeError: pass ret4 = re.search(r'(?P<x>[-]?d+.?d*)(?P<mark>[+-])(?P<y>[-]?d+.?d*)', re_str) try: while ret4.group(): re_str = re_str.replace(ret4.group(), str(math(ret4.groupdict()))) ret4 = re.search(r'(?P<x>[-]?d+.?d*)(?P<mark>[+-])(?P<y>[-]?d+.?d*)', re_str) except AttributeError: return re_str def main(user_inp): while True: if not re.search('([+*/d.-]*)', user_inp): print(user_inp) return suansu(user_inp) else: for i in re.findall('([+*/d.-]*)', user_inp): user_inp = user_inp.replace(i, suansu(i.replace('(', '').replace(')', ''))) while True: print(main('0+'+input('>>>').replace(" ", "")))
