尝试在 dict 中迭代浮点数

如何解决尝试在 dict 中迭代浮点数

我正在尝试完成此功能，但无济于事，因为字典包含我正在尝试总计的浮点值。

这是我目前的代码：

def add_prices(basket):
    # Initialize the variable that will be used for the calculation
    total = 0
    # Iterate through the dictionary items
    for groceries,prices in basket.items():
        # Add each price to the total calculation
        for price in prices:
        # Hint: how do you access the values of
        # dictionary items?
            total += price.values()
    # Limit the return value to 2 decimal places
    return round(total,2) 

groceries = {"bananas": 1.56,"apples": 2.50,"oranges": 0.99,"bread": 4.59,"coffee": 6.99,"milk": 3.39,"eggs": 2.98,"cheese": 5.44}

print(add_prices(groceries)) # Should print 28.44

我完全傻眼了，需要帮助，因为我尝试通过类型转换直接将价格分配给值。任何帮助将不胜感激！

解决方法

您不必遍历 prices，因为它们已经是 float 值。因此，浮动的错误消息是不可迭代的。

groceries = {"bananas": 1.56,"apples": 2.50,"oranges": 0.99,"bread": 4.59,"coffee": 6.99,"milk": 3.39,"eggs": 2.98,"cheese": 5.44}

def add_prices(basket):
    total = 0
    for groceries,prices in basket.items():
        total += prices
    return round(total,2) 

add_prices(groceries)
#28.44

正如评论中所提到的，将您的函数更改为单行代码可能更容易，这样您就可以避免 for 循环

def add_prices(basket):
    return round(sum(basket.values()),2)
add_prices(groceries)
#28.44

,

您不必要地执行另一个循环。可以直接加价。 阅读dict.keys()、dict.values()、dict.items。

应该是这样

def add_prices(basket):
    # Initialize the variable that will be used for the calculation
    total = 0
    # Iterate through the dictionary items
    for groceries,prices in basket.items():
        total += prices
        # Add each price to the total calculation
        #for price in prices:
        # Hint: how do you access the values of
        # dictionary items?
            #total += price.values()
    # Limit the return value to 2 decimal places
    return round(total,2) 

print(add_prices(groceries)) 
>>> 28.44

,

我不知道你为什么在主循环中做了第二个循环，你可以直接这样做，

def add_prices(basket):
   # Initialize the variable that will be used for the calculation
   total = 0
   # Iterate through the dictionary items
   for groceries,prices in basket.items():
      total += prices
   # Limit the return value to 2 decimal places
   return round(total,2)