Question

我试图将一些代码分解为同一文件中的较小子程序，以使其更加模块化。这是我想要分解的代码：

def time():
    print("This program calculates the number of seconds in a given length of 
        time.\n")
    second = 1
    minute = second * 60
    hour = minute * 60
    day = hour * 24
    week = day * 7
    number1 = (eval(input("Enter a number of weeks: ")))
    calc1 = number1 * week
    number2 = (eval(input("Enter a number of days: ")))
    calc2 = number2 * day
    number3 = (eval(input("Enter a number of hours: ")))
    calc3 = number3 * hour
    number4 = (eval(input("Enter a number of minutes: ")))
    calc4 = number4 * minute
    number5 = (eval(input("Enter a number of seconds: ")))
    calc5 = number5 * second
    sum1 = (calc1 + calc2 + calc3 +calc4 + calc5)
    print("\nIn", number1, "week(s),", number2, "day(s),", number3, "hour(s),", 
        number4, "minute(s), and", number5, "second(s), there are", sum1, 
        "second(s).")

当它全部在一起时，它的工作方式与我想要的方式相同，但我想在某个方面将其分解：

def count():
    print("This program calculates the number of seconds in a given length of 
        time.\n")
    second = 1
    minute = second * 60
    hour = minute * 60
    day = hour * 24
    week = day * 7

def number():
    number1 = (eval(input("Enter a number of weeks: ")))
    calc1 = number1 * week
    number2 = (eval(input("Enter a number of days: ")))
    calc2 = number2 * day
    number3 = (eval(input("Enter a number of hours: ")))
    calc3 = number3 * hour
    number4 = (eval(input("Enter a number of minutes: ")))
    calc4 = number4 * minute
    number5 = (eval(input("Enter a number of seconds: ")))
    calc5 = number5 * second
    sum1 = (calc1 + calc2 + calc3 +calc4 + calc5)

def time():
    print("This program calculates the number of seconds in a given length of 
        time.")
    count()
    number()
    print("In,", number1, "weeks,", number2, "days,", number3, "hours,", 
        number4, "minutes, and", number5, "seconds, there are", sum1, 
        "seconds.")

time()

目标是运行time（）并调用count（）和number（），因此time（）的代码不会那么长。（我知道原始代码不长，但我正在努力学习这一切是如何工作的。）

之前我已成功调用文件中的函数，但只有在打印字符串时才会成功，并且不涉及数学。我试过玩参数，回归和谷歌搜索甚至咬牙切齿，但无济于事。我最终会遇到这样的错误：

Traceback (most recent call last):
  File "<pyshell#525>", line 1, in <module>
    time()
  File "<pyshell#524>", line 4, in time
    number()
  File "<pyshell#522>", line 3, in number
    calc1 = number1 * week
NameError: name 'week' is not defined

我是编程的新手，所以我确信我错过了一些非常简单的东西，但是我无法自己解决这个问题并希望得到任何帮助。

Answer 1

因此，您需要了解的最重要的事情是范围。在函数内声明变量时，只能在该函数中使用该变量。因此，例如，当您在count函数内部声明一周时，您只能访问变量＆＃34; week＆＃34;当你在函数内部时。

如果要从程序内的任何位置访问变量，则需要全局声明它。这是代码的工作版本，其中时间变量是全局声明的。

print("This program calculates the number of seconds in a given length of time.\n")
second = 1
minute = second * 60
hour = minute * 60
day = hour * 24
week = day * 7

def number():
    number1 = (int(input("Enter a number of weeks: ")))
    calc1 = number1 * week
    number2 = (int(input("Enter a number of days: ")))
    calc2 = number2 * day
    number3 = (int(input("Enter a number of hours: ")))
    calc3 = number3 * hour
    number4 = (int(input("Enter a number of minutes: ")))
    calc4 = number4 * minute
    number5 = (int(input("Enter a number of seconds: ")))
    calc5 = number5 * second
    sum1 = (calc1 + calc2 + calc3 +calc4 + calc5)
    print("In,", number1, "weeks,", number2, "days,", number3, "hours,",
        number4, "minutes, and", number5, "seconds, there are", sum1,
        "seconds.")

def time():
    print("This program calculates the number of seconds in a given length of time.")
    number()


time()

您需要小心全局变量，因为如果使用太多变量，可能会遇到问题。在尝试编写更复杂的程序之前，我建议阅读this article，它可以很好地解释范围和名称空间在python中的工作方式。

Answer 2

问题：...在同一个文件中，使其更加模块化

您根本不需要def count()。
所有values都是常数，因此应该这样定义无需一遍又一遍地计算values。

您可以使其更加模块化，例如：

SECONDS = {'s':1, 'm': 1*60, 'h':60*60, 'd':60*60*24, 'w': 60*60*24*7}
def get_input():
    result = {'sum1':0}
    for cat in ['weeks', 'days', 'hours', 'minutes', 'seconds']:
        value = int( input( "Enter a number of {}: ".format(cat) ))
        result[cat] = value
        result['sum1'] += SECONDS[ cat[:1] ] * value
    return result

def time():
    result = get_input()
    print("\nIn, {weeks}, week(s), {days}, day(s), {hours}, hour(s),"
          " {minutes}, minute(s), and, {seconds} second(s), "
          "there are, {sum1} second(s)."\
          .format(**result))

if __name__ == '__main__':
    print("This program calculates the number of seconds in a given length of time.\n")
    time()

通常使用 __main__ 入口点是很常见的。
这使您能够从其他python脚本调用def get_input()。

使用Python测试：3.4.2和2.7.9

Answer 3

您可以让count返回dict，例如：

def count():
    times = {'second': 1}
    times['minute'] = times['second'] * 60
    times['hour'] = times['minute'] * 60
    times['day'] = times['hour'] * 24
    times['week'] = times['day'] * 7
    return times

然后，您可以在count中致电time并将其传递给number：

def time():
    ...
    times = count()
    values = number(times)



def number(times):
    values = {}
    number1 = int(input("Enter a number of weeks: "))
    calc1 = number1 * times['week']
    values.update({'number1': number1, 'calc1': calc1})
    ...
    sum1 = calc1 + calc2 + calc3 + calc4 + calc5
    values['sum1'] = sum1
    return values

然后您可以使用从数字返回的字母来填充time

末尾的印刷品

如何在Python中的同一文件中调用另一个函数内的函数？

3 个答案: