Coding for loop or while loop?

[Trickmaster]

Which function definition body is better/more likely to be used, even though they do the same task?

def count_to_first_vowel(s):
''' (str) -> str
Return the substring of s up to but not including the first vowel in s. If no vowel
is present, return s.
>>> count_to_first_vowel('hello')
'h'
>>> count_to_first_vowel('cherry')
'ch'
>>> count_to_first_vowel('xyz')
xyz
'''
substring = ''
for char in s:
if char in 'aeiouAEIOU':
return substring
substring = substring + char
return substring

or

def count_to_first_vowel(s):
''' (str) -> str
Return the substring of s up to but not including the first vowel in s. If no vowel
is present, return s.
>>> count_to_first_vowel('hello')
'h'
>>> count_to_first_vowel('cherry')
'ch'
>>> count_to_first_vowel('xyz')
xyz
'''
substring = ''
i = 0
while i < len(s) and not s in 'aeiouAEIOU':
substring = substring + s
i = i + 1
return substring

@alyphen @repository

 

[Trickmaster]

Sorry about the spacing, it posted wrong :P

 

[Trickmaster]

def count_to_first_vowel(s):
    '''  (str) -> str
    Return the substring of s up to but not including the first vowel in s. If no vowel
    is present, return s.
    >>> count_to_first_vowel('hello')
    'h'
    >>> count_to_first_vowel('cherry')
    'ch'
    >>> count_to_first_vowel('xyz')
    xyz
    '''
    substring = ''
    for char in s:
        if char in 'aeiouAEIOU':
            return substring
        substring = substring + char
    return substring

or

def count_to_first_vowel(s):
    '''  (str) -> str
    Return the substring of s up to but not including the first vowel in s. If no vowel
    is present, return s.
    >>> count_to_first_vowel('hello')
    'h'
    >>> count_to_first_vowel('cherry')
    'ch'
    >>> count_to_first_vowel('xyz')
    xyz
    '''
    substring = ''
    i = 0
    while i < len(s) and not s[i] in 'aeiouAEIOU':
        substring = substring + s
        i = i + 1
    return substring

 

[Trickmaster]

^^Forgot about the code option, that helps

 

[not2excel]

the main differences between the standard for (fori) loop and while loop are the reason you use them. If you know beforehand how many times you wish to loop, eg. the number of indices in a collection or just say 10 times. While loops are best for condition checking in which the condition could be false at any point in time over the course of the loop dispatchment

 

[Trickmaster]

If you know beforehand how many times you wish to loop, eg. the number of indices in a collection or just say 10 times.

So, you would use a for loop in this situation? How could you control it so the function only iterates 10 times in a for loop?

 

[alyphen]

So, you would use a for loop in this situation? How could you control it so the function only iterates 10 times in a for loop?

In this situation you would use a for loop, since you're running a predetermined number of iterations (based on the string length)
If you are finding out how many iterations later (based on a condition), that is when you use the while loop.
This is pretty much what @not2excel outlined, but I hope it makes it clearer.

 

[NanoNet]

alyphen gave the perfect answer...! But if your looking for a quicker, and easier way to get your questions answered, go to www.stackoverflow.com. If you post a question there, you will get an answer within minutes. It's helped me a ton in my adventure of learning basic knowledge to some higher level stuff :P

 

[Trickmaster]

alyphen gave the perfect answer...! But if your looking for a quicker, and easier way to get your questions answered, go to www.stackoverflow.com. If you post a question there, you will get an answer within minutes. It's helped me a ton in my adventure of learning basic knowledge to some higher level stuff :p

Thanks! That helps a lot, I'll def use it :P