Question

def calculator(): 
    print("When prompted to enter a symbol, enter:\n'+' to add,\n'-' to subtract,\n'*' to multiply,\n'/' to divide,\n'^' to calculate powers,") 
    print("',\n'=' to get the answer.") 
    again = None 
    while again != "x": 
     answer = float(input("\nEnter number: ")) 
     while 1 == 1: 
      symbol = input("Enter symbol: ") 
      if symbol == "=": 
       print("\nThe answer is ", answer, ".", sep = "") 
       again = input("\nEnter 'a' to use the calculator again and 'x' to exit: ") 
       break 
      number = float(input("Enter number: ")) 
      #trying to use a dictionary instead of "if" statements present in docstring 
      dictionary = {"+": answer += number, "-": answer -= number, "*": answer *= number, "/": answer /= number, "^": answer **= number} 
      dictionary[symbol] 
      """if symbol == "+": 
       answer += number 
      if symbol == "-": 
       answer -= number 
      if symbol == "*": 
       answer *= number 
      if symbol == "/": 
       answer /= number 
      if symbol == "^": 
       answer **= number""" 

我覺得有一堆「if」語句是WET代碼（如文檔字符串中所示）。我想對基於用戶輸入符號的數字進行操作，但即使我只在字典中保留作爲操作符的符號的值（即，僅「+」：+，「 - 」 ： - 等字典）

編輯： 我想要更少的代碼，所以請不要告訴我做一個函數來調用。

Answer 1

您必須爲您的操作定義函數並將它們存儲在字典中。例如：

def plus (a, b): 
    return a+b 

def minus (a, b): 
    return a-b 

my_dict = {"+" : plus, "-" : minus} 

answer = my_dict[symbol](answer, number) 

至少這應該會給你一個想法。