CODEWITHSUNDEEP
pythonpython-2.7list
Feelsbadman
Feelsbadman

Reputation: 1165

python insert function list comprehentions

I am trying to write a 4-5 line code in a single line by using list-comprehentions. But the problem here is that I am not able to use the insert funciton so im wondering if there is a work-around for this?

Original code:

def order(text):
    text = text.split()
    for x in text:
        for y in x:
            if y in ('1','2','3','4','5','6','7','8','9'):
                final.insert(int(y)-1, x)

    return final

What i have tried so far:

return [insert(int(y)-1, x) for x in text.split() for y in x if y in ('1','2','3','4','5','6','7','8','9')]

But i have faced the following error:
NameError: global name 'insert' is not defined

I have tried to use insert because the task is to re-arrange items in the list by using the number that appears in each word.

for example i have is2 Th1is T4est 3a as input and it should come out as:
Th1is is2 3a T4est

Upvotes: 3

Views: 151

Answers (2)

Blender
Blender

Reputation: 298196

You can implement your original idea by splitting your code up into a few simple functions and make a list of the proper size (filled with Nones) to hold the final ordering of the words:

def extract_number(text):
    return int(''.join(c for c in text if c.isdigit()))

def order(text):
    words = text.split()
    result = [None] * len(words)

    for word in words:
        result[extract_number(word) - 1] = word

    return ' '.join(result)

You can also do this in one line using sorted():

def extract_number(text):
    return int(''.join(c for c in text if c.isdigit()))

def order(text):
    return ' '.join(sorted(text.split(), key=extract_number))

Upvotes: 1

tobias_k
tobias_k

Reputation: 82899

Instead of using list comprehensions, you should just sort the list using those numbers in the key function, e.g. extracting the numbers using a regular expression.

>>> import re
>>> s = "is2 Th1is T4est 3a"
>>> p = re.compile("\d+")
>>> sorted(s.split(), key=lambda x: int(p.search(x).group()))
['Th1is', 'is2', '3a', 'T4est']

Upvotes: 4

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