如何将字符串仅附加到列表中的辅音?

时间:2014-09-27 15:30:16

标签: python list python-2.7

现在我正试图创建一个反对的翻译。也就是说,在连续的辅音或几个辅音之后,你可以添加' op'那些信件。例如,牛会成为copowop或街道,将成为stropeetop。这就是我到目前为止所做的:

def oppish(phrase): #with this function I'm going to append 'op' or 'Op' to a string.
    consonants =  ['b','c','d','f','g','h','i','j','k','l','m','n','p','q','r','s','t','v','w','x','y','z']
    vowels = ['a', 'e', 'i', 'o', 'u'] #this and the preceding line create a variable for the vowels we will be looking to append 'op' to.    
    if phrase == '':    #error case. if the input is nothing then the program will return False.
        return False
    phrase_List = list(' ' + phrase) # turns the input phrase into a list which allows for an        index to search for consonants later on.
    new_phrase_List = list() #creates new list for oppish translation
    for i in range(1, len(phrase_List)):
        if phrase_List[i] == phrase_List[1]:
            new_phrase_List.append(phrase_List[i])
        elif phrase_List[i] in consonants:
            new_phrase_List.append('op') #adds op to the end of a consonant within the list and then appends it to the newlist
        new_phrase_List.append(phrase_List[i]) #if the indexed letter is not a consonant it is appended to the new_phrase_list.
    print 'Translation: ' + ''.join(new_phrase_List)

oppish('street')

这里唯一的问题是上面的代码产生了这个

Translation: ssoptopreeopt

我不确定自己做错了什么,我尝试过可视化工具,但无济于事。所有帮助表示赞赏! :)

2 个答案:

答案 0 :(得分:2)

这非常适合itertools.groupby,它允许您使用键功能将项目分组到iterable中。该组将累积,直到键函数的返回值发生变化,此时group将产生键函数的返回值和迭代器对累积组的返回值。在这种情况下,如果字母是元音,我们希望我们的键函数返回True。这样,我们就会得到一组连续的辅音,以及来自groupby的连续元音组:

from itertools import groupby

vowels = {'a', 'e', 'i', 'o', 'u'}  # set instead of list, because lookups are O(1)

def oppish(phrase):
    if not phrase:
        return False

    out  = []
    for is_vowel, letters in groupby(phrase, lambda x: x in vowels):
        out.append(''.join(list(letters)))
        if not is_vowel:
            out.append('op')
    return ''.join(out)


print oppish('street')
print oppish('cow')

输出:

stropeetop
copowop

答案 1 :(得分:0)

我认为问题在于你解决问题的方法。 尝试做这样的事情:

编辑:虽然在这个问题中有更好的(pythonic)答案(感谢dano),但这个答案不需要额外的库

vowels = ['a', 'e', 'i', 'o', 'u']

def oppish(word):
    result = []
    first = True
    prev_vowel = False

    for letter in list(word):
        if (letter in vowels) and (not first) and (not prev_vowel):
            result.append('op')
            prev_vowel = True
        else:
            prev_vowel = False

        result.append(letter)
        first = False
        if not prev_vowel:
            result.append('op')
        print ''.join(result)


oppish('street')

#> stropeetop

提示:不要浪费时间来定义元音和辅音。事实上,有元音和非元音