Python 计算器作业 Re模块

cal.py

#!/usr/bin/env python
# -*- coding:utf8 -*-
import re
def calculation(x,y,m):
    if m=='+' or m=='--':
        return x+y
    elif m=="-" or m=='+-' or m=='-+':
        return x - y
    elif m == "*":
        return x * y
    elif m == "/":
        return x / y
    elif m == "%":
        return x % y
    elif m == "//":
        return x // y
    elif m == "**":
        return x**y
    else:
        print('This mark is not exist, mark:%s' %m)
        return 0
def subcal(a):
    while True:
        temb = re.search('\d*\.?\d+[\*\/\%]+[\+\-]?\d*\.?\d+', a)  # 高级别运算符*/%//**
        if temb == None:
            break
        temb = temb.group()
        c = re.findall('[\+\-]?\d*\.?\d+', temb)  #高级别运算符时，对应的正负号算是数值的一部分
        d = re.findall('[\*\/\%]+', temb)
        tem = calculation(float(c[0]), float(c[1]), d[0])
        a = a.replace(temb, str(tem), 1)
    while True:
        temb = re.search('[\+\-]?\d*\.?\d+[\+\-]+\d*\.?\d+', a)  # +-运算 [\+\-]+\d*\.?\d+， 取首字符是加减符号的情况
        if temb == None:
            break
        temb = temb.group()
        c = re.findall('(\d*\.?\d+)', temb)
        d = re.findall('[\+\-]+', temb)
        if len(d)>1: #如果数量大于1，证明首字符是正负号，与数字一起计算
            tem = calculation(float(''.join([d[0],c[0]])), float(c[1]), d[-1])
        else:
            tem = calculation(float(c[0]), float(c[1]), d[0])
        a = a.replace(temb, str(tem), 1)
    return a

if __name__=="__main__":

    s = '1 - 2 * ((60-30+(40+4 / 2+4/ -2+3)*(9-2*5/-3+7/3*9/4*2 +10*56 /14))-(-4*3)/(16-3*2))'
    # s='1+2'
    # s='1-2'
    # s='3+2-9'
    # s='-5+2+1'
    # s='-1+9/3'
    # s='9+5*2-10-9//5-1+3**2'
    # s='9//5'
    print(eval(s))
    s=s.replace(" ","")
    while True: #计算括号内数值，从最里层括号开始计算所有括号
        tema=re.search('\([^()]+\)',s) #最里边括号
        if tema == None:
            break
        tema=tema.group()
        a = re.sub('\(|\)', '', tema)  # 去掉括号，只保留计算
        # a=tema.replace('(','')
        # a = a.replace(')', '') #去掉括号，只保留计算
        a=subcal(a)
        s=s.replace(tema,str(a),1)
    s=float(subcal(s)) #转为浮点
    s=int(s) if s==int(s) else s #如果是整数，取整
    print(s)

 

s1.py

#!/usr/bin/env python
# -*- coding:utf8 -*-
import re
from cal import subcal

s = '1 - 2 * ((60-30+(40+4 / 2+4/ -2+3)*(9-2*5/-3+7/3*9/4*2 +10*56 /14))-(-4*3)/(16-3*2))'
# s='1+2'
# s='1-2'
# s='3+2-9'
# s='-5+2+1'
# s='-1+9/3'
# s='9+5*2-10-9//5-1+3**2'
# s='9//5'
s='19%-5'
print(eval(s))
s=s.replace(" ","")
while True: #计算括号内数值，从最里层括号开始计算所有括号
    tema=re.search('\([^()]+\)',s) #最里边括号
    if tema == None:
        break
    tema=tema.group()
    a = re.sub('\(|\)', '', tema)#去掉括号，只保留计算
    # a=tema.replace('(','')
    # a = a.replace(')', '') #去掉括号，只保留计算
    a=subcal(a)
    s=s.replace(tema,str(a),1)
s=float(subcal(s)) #转为浮点
s=int(s) if s==int(s) else s #如果是整数，取整
print(s)