Question

我是初学者程序员，我一直在完成zedshaw的Learn Python The Hard Way课程，但是在练习26中，我们给出了一个有缺陷的代码，以便我们可以调试它。尽管代码是使用Python 2.x编写的，但我已经在Python 3中重写它们，所以我可以学习它。

它引发了以下错误：

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

原始代码：link（这是练习文件）

所以我的问题是：

为什么退出代码1完成？
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，所以你基本上用一个参数调用.format() - 元组。尝试在*前面加secret_formula()：

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

为什么退出代码1完成？

因为你收到错误。

为什么不继续执行代码？

因为你收到错误。

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的版本是：

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 - 语句现在是print()函数。

现在，这段代码当然已经破解了，因为它缺少一个右括号，并且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))

如果您想要转换为新的.format()格式而不是旧的%格式，那么它将如下所示：

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

但这不是必要的。

Answer 3

正确答案如下：

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)

我的python代码出了什么问题？

3 个答案: