爲什麼我的代碼不工作？在介紹 林到Python類和它真的晚與任何人聯繫

Question

def main(): 
    name = input("What is your first name?: ") 
    name2 = input("What is your last name?: ") 
    kg = float(input("What is your weight in kilograms?: ")) 
    meters = float(input("What is your height in meters?: ")) 
    mass = float(kg) 
    height = float(meters) 
    Health(BMI, Ponderal, Rohrer) 
    print(name2+",",name,"(BMI:",BMI,",",\ 
     "Ponderal Index:",Ponderal,",","Rohrer's Index:",Rohrer,",",")") 

***應該沿着 最後，第一（114：35.234，出生體重指數：16.5，羅勒的指數BMI）行返回的東西其他人的幫助。這個練習的全部目的是創建功能並回復給他們。

編輯：非常感謝您的幫助球員，我知道了很多關於這裏的問題是通常先進得多，但快速答覆和有用的提示量是極大的讚賞。

Answer 1

如果函數返回的東西，那麼你應該把它的地方。例如，在一個變量！

這裏，改變你的功能：

def main(): 
    name = input("What is your first name?: ") 
    name2 = input("What is your last name?: ") 
    mass = float(input("What is your weight in kilograms?: ")) 
    height = float(input("What is your height in meters?: ")) 
    #mass = float(kg) #not needed 
    #height = float(meters) #not needed 
    result = health(mass, height) 
    #printing based on the return value. result[0] is bmi, and so on. 

    print("%s, %s (BMI: %d, Ponderal Index: %d, Rohrer's Index: %d"%(name2,name,health[0],health[1],health[2])) 

def bmi (mass, height): 
    result = mass/(height ** 2) 
    return result 

def ponderal (mass, height): 
    result = mass/height ** 3 
    return result 

def rohrer(mass, height): 
    result = (mass * 10000)/((height * 100) ** 3) 
    return result 

def health (mass, height): 
    #calling the functions 
    bmi = bmi(mass, height) #store the returned value to a variable 
    ponderal = ponderal(mass, height) 
    rohrer = rohrer(mass, height) 
    return [bmi,ponderal,rohrer] #return it as a list. 

結果：

>>> ================================ RESTART ================================ 
>>> 
What is your first name?: Akhyar 
What is your last name?: Kamili 
What is your weight in kilograms?: 50 
What is your height in meters?: 1.7 
Kamili, Akhyar (BMI: 17.301038062283737 , Ponderal Index: 10.177081213108082 , Rohrer's Index: 0.1017708121310808 ,) 
>>> 

幾點建議：

1. 不要利用函數名！
2. 不要命名變量，如函數！

你的代碼會做得更好。

Answer 2

你不是在調用這些函數，而只是引用它們。例如：

Ponderal 
# <function Ponderal at blah> 

相比：

Ponderal() 
# A number 

Answer 3

你的代碼有很多問題;首先格式化它更好地確保您對您的代碼有意見（以＃開始的行）

也不要直接將字符串的單位轉換爲浮點數。如果他們輸入無效的句柄異常會怎麼樣。

第三，你格式化輸出文本的方式是非常糟糕的，它很難閱讀所有的逗號和副詞。

此外，您獲得的值的方式，你從來沒有將它們設置爲變量你也使用這個健康功能，你不需要直接調用值！

還可以使用無意義的名字變量而不是NAME2使用名字等

您的代碼應更好如下所示（請注意，如果這是家庭作業，你把這個在你的教授將容易找到它計算器;所以不要）

# calculates the BMI of a person 
def BMI (mass, height): 
    BMI = mass/(height ** 2) 
    return BMI 

# calculates the Ponderal index of a person 
def Ponderal (mass, height): 
    Ponderal = mass/height ** 3 
    return Ponderal 
# calculates the Rohrer index of a person 
def Rohrer (mass, height): 
    Rohrer = (mass * 10000)/((height * 100) ** 3) 
    return Rohrer 

# this isn't needed 
def Health (BMI, Ponderal, Rohrer): 
    BMI (mass, height) 
    Ponderal (mass, height) 
    Rohrer (mass, height) 
    return Health 


def main(): 
    # get the names of people 
    first_name = input("What is your first name?: ") 
    last_name = input("What is your last name?: ") 

    # get their height and weight 
    kg  = input("What is your weight in kilograms?: ") 
    meters = input("What is your height in meters?: ") 

    # convert mass and height to numbers 
    try: 
     mass = float(kg) 
    except ValueError: 
     print "Please enter a valid mass." 
     return 

    try: 
     height = float(meters) 
    except ValueError: 
     print "Please enter a valid height." 
     return 

    # call the BMI, Ponderal and Rohrer functions 
    # don't make the variable BMI as your function is also that name! 
    bmi_value = BMI(mass, height) 
    ponderal_value = Ponderal(mass, height) 
    rohrer_value = Rohrer(mass, height) 

    print("%s, %s (BMI: %s, Ponderal Index: %s, Rohrer Index: %s)" % (last_name, first_name, bmi_value, ponderal_value, rohrer_value)) 

    # this print string is EXTREEMLY hard to read 
    # print(name2+",",name,"(BMI:",BMI,",", "Ponderal Index:",Ponderal,",","Rohrer's Index:",Rohrer,",",")") 

# if we are running this script directly call main 
if __name__ == "__main__": 
    main()