Convert a number to a list of integers

Question:

How do I write the magic function below?

>>> num = 123
>>> lst = magic(num)
>>>
>>> print lst, type(lst)
[1, 2, 3], <type 'list'>
Asked By: user94774

||

Answers:

You mean this?

num = 1234
lst = [int(i) for i in str(num)]
Answered By: Bjorn

You could do this:

>>> num = 123
>>> lst = map(int, str(num))
>>> lst, type(lst)
([1, 2, 3], <type 'list'>)
Answered By: John Fouhy
a = 123456
b = str(a)
c = []

for digit in b:
    c.append (int(digit))

print c
Answered By: RedBlueThing

Don’t use the word list as variable name! It is a name of python built in data type.

Also, please clarify your question. If you are looking for a way to create a one-member list, do the following:

a = 123
my_list = [a]

and “pythonizing” Cannonade’s answer:

a = 123
my_list = [int(d) for d in str(a)]
Answered By: Boris Gorelik
magic = lambda num: map(int, str(num))

then just do

magic(12345) 

or

magic(someInt) #or whatever
Answered By: Alex

Just use :

a= str (num)
lst = list(a)
Answered By: MrDHat
>>> from collections import deque
>>> def magic(num):
        digits = deque()
        while True:
            num,r = divmod(num,10)
            digits.appendleft(r)
            if num == 0:
                break
        return list(digits)

>>> magic(123)
[1, 2, 3]

According to my timings, this solution is considerably faster than the string method (magic2), even for smaller examples.

>>> def magic2(num):
        return [int(i) for i in str(num)]

Timings:

magic

>>> timeit.timeit(setup='from __main__ import magic', stmt='magic(123)')
1.3874572762508706
>>> timeit.timeit(setup='from __main__ import magic', stmt='magic(999999999)')
3.2624468999981673

magic2

>>> timeit.timeit(setup='from __main__ import magic2', stmt='magic2(123)')
3.693756106896217    
>>> timeit.timeit(setup='from __main__ import magic2', stmt='magic2(999999999)')
10.485281719412114
Answered By: jamylak
num = map(int, list(str(num)))
Answered By: wilbeibi

If it is named as magic, why not just use magic:

def magic(x):
    if x < 10:
        return [x]
    else:
        return magic(x//10) + [x%10]
Answered By: englealuze

You can try this:

def convert_to_list(number):
    return list(map(lambda x: int(x), str(number)))

convert_to_list(1245)
Answered By: Anthony

for python 3.x:

num = 1234
lst = list(map(int, str(num)))
Answered By: Marko Tankosic
Categories: questions Tags: , ,
Answers are sorted by their score. The answer accepted by the question owner as the best is marked with
at the top-right corner.