我的 python 代码有什么问题？

Question

我是一名初级程序员，我一直在完成 zedshaw 的 Learn Python The Hard Way 课程，但是在练习 26 中，我们得到了一个有缺陷的代码，因此我们可以对其进行调试。虽然代码是使用 Python 2.x 编写的，但我一直在用 Python 3 重新编写它们，以便我可以学习它。

它会引发以下错误：

Traceback (most recent call last):
  File "/home/omar/PycharmProjects/Python_The_Hardway/ex26_Quiz.py", line 76, in <module>
    print("We'd have {} beans, {} jars, and {} crates".format(secret_formula(start_point)))
IndexError: tuple index out of range

这是我的代码：link

原代码：link（这是练习文件）

所以我的问题是：

• 为什么它以退出代码 1 结束？
• 为什么不继续执行代码？
• 如何使用 Python 3 重写它？

谢谢

Answer 1

secret_formula 方法返回一个元组，因此您实际上是在使用单个参数（元组）调用 .format()。尝试在secret_formula() 前面加上*：

print("We'd have {} beans, {} jars, and {} crates".format(*secret_formula(start_point)))

这会将元组视为单独的参数，应该修复它。

Answer 2

为什么它以退出代码 1 结束？

因为你得到一个错误。

为什么不继续执行代码？

因为你得到一个错误。

如何使用 Python 3 重写它？

原始的 Python 2 代码如下所示：

print "We'd have %d beans, %d jars, and %d crabapples." % secret_formula(start_pont

Python 3 版本是：

print("We'd have %d beans, %d jars, and %d crabapples." % secret_formula(start_pont)

我在要打印的内容周围添加了括号，因为 print-statement 现在是 print() 函数。

现在，这段代码当然被破坏了，因为它缺少右括号，而且start_point 拼写错误。所以它应该是：

print("We'd have %d beans, %d jars, and %d crabapples." % secret_formula(start_point))

如果您想改用新的.format() 格式而不是旧的% 格式，那么它看起来像这样：

print("We'd have {:d} beans, {:d} jars, and {:d} crabapples.".format(*secret_formula(start_point))

但这不是必须的。

Answer 3

下面给出正确答案

def break_words(stuff):
        """This function will break up words for us."""
        words = stuff.split(' ')
        return words

    def sort_words(words):
        """Sorts the words."""
        return sorted(words)

    def print_first_word(words):
        """Prints the first word after popping it off."""
        word = words.pop(0)
        print word

    def print_last_word(words):
        """Prints the last word after popping it off."""
        word = words.pop(-1)
        print word

    def sort_sentence(sentence):
        """Takes in a full sentence and returns the sorted words."""
        words = break_words(sentence)
        return sort_words(words)

    def print_first_and_last(sentence):
        """Prints the first and last words of the sentence."""
        words = break_words(sentence)
        print_first_word(words)
        print_last_word(words)

    def print_first_and_last_sorted(sentence):
        """Sorts the words then prints the first and last one."""
        words = sort_sentence(sentence)
        print_first_word(words)
        print_last_word(words)


    print "Let's practice everything."
    print 'You\'d need to know \'bout escapes with \\ that do \n newlines and \t tabs.'

    poem = """
    \tThe lovely world
    with logic so firmly planted
    cannot discern \n the needs of love
    nor comprehend passion from intuition
    and requires an explantion
    \n\t\twhere there is none.
    """


    print "--------------"
    print poem
    print "--------------"

    five = 10 - 2 + 3 - 5
    print "This should be five: %s" % five

    def secret_formula(started):
        jelly_beans = started * 500
        jars = jelly_beans / 1000
        crates = jars / 100
        return jelly_beans, jars, crates


    start_point = 10000
    beans, jars, crates = secret_formula(start_point)

    print "With a starting point of: %d" % start_point
    print "We'd have %d jeans, %d jars, and %d crates." % (beans, jars, crates)

    start_point = start_point / 10

    print "We can also do that this way:"
    print "We'd have %d beans, %d jars, and %d crabapples." % secret_formula(start_point)


    sentence = "All god\tthings come to those who weight."

    #python_exercise.break_words(sentence)
    #words = python_exercise.break_words(sentence)
    #python_exercise.sort_words(words)
    #sorted_words = python_exercise.sort_words(words)

    #print_first_word(words)
    #print_last_word(words)
    #print_first_word(sorted_words)
    #print_last_word(sorted_words)
    #sorted_words = python_exercise.sort_sentence(sentence)
    #print sorted_words

    #print_first_and_last(sentence)

    #print_first_a_last_sorted(sentence)