磅到公制 python 程序

Question

def poundsToMetric(pounds):
    kilograms = pounds / 2.2
    grams = kilograms * 1000
    return int(kilograms), grams % 1000

pounds = float(input("How many Pounds? "))
kg, g = poundsToMetric(pounds)
print('The amount of pounds you entered is {}. '\
      'This is {} kilograms and {} grams.'.format(pounds, kg, g))

這個程序有效，但我想知道如何讓公斤只帶小數點，而不是像 545.4544545454 克這樣的 65 磅，我需要它是 545 克

Answer 1

有兩種方式：

1. 使用round()內置函數

   def poundsToMetric(pounds): kilograms = pounds / 2.2 grams = kilograms * 1000 return int(kilograms), grams % 1000 pounds = float(input("How many Pounds? ")) kg, g = poundsToMetric(pounds) print('The amount of pounds you entered is {}. This is {} kilograms and {} grams.'.format(pounds, kg, round(g)))

2. 使用int()轉換來獲取值的整數部分：

    def poundsToMetric(pounds): kilograms = pounds / 2.2 grams = kilograms * 1000 return int(kilograms), grams % 1000 pounds = float(input("How many Pounds? ")) kg, g = poundsToMetric(pounds) print('The amount of pounds you entered is {}. This is {} kilograms and {} grams.'.format(pounds, kg, int(g)))

分別查看以下每種方式的輸出：

➜  python help.py
How many Pounds? 65
The amount of pounds you entered is 65.0. This is 29 kilograms and 545.0 grams.

➜  python help.py
How many Pounds? 65
The amount of pounds you entered is 65.0. This is 29 kilograms and 545 grams.

Answer 2

如果添加行

print type(grams%1000)

你會得到輸出

<type 'float'> 

所以這顯然是返回一個浮點數。 將其轉換為int以獲得所需的結果。

而不是這樣做：

return int(kilograms), grams % 1000

做這個：

return int(kilograms), int(grams % 1000)

現在你的程序的輸出是：

The amount of pounds you entered is 65. This is 29 kilograms and 545 grams.

正是你想要的。