How do I write the magic
function below?
>>> num = 123
>>> lst = magic(num)
>>>
>>> print lst, type(lst)
[1, 2, 3], <type 'list'>
How do I write the magic
function below?
>>> num = 123
>>> lst = magic(num)
>>>
>>> print lst, type(lst)
[1, 2, 3], <type 'list'>
a = 123456
b = str(a)
c = []
for digit in b:
c.append (int(digit))
print c
You could do this:
>>> num = 123
>>> lst = map(int, str(num))
>>> lst, type(lst)
([1, 2, 3], <type 'list'>)
>>> 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
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)]
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]
You can try this:
def convert_to_list(number):
return list(map(lambda x: int(x), str(number)))
convert_to_list(1245)