This question already has an answer here:
How to join mixed list (array) (with integers in it) in Python?
(1 answer)
Closed 3 years ago.
I have the list below, which contains strings and integers. How do I make a string of them? Tried to use
''.join(l)
but it does't work, because there are integers on the list(specifically, L[1] is an integer, and the others are all strings.). Can you help?
L=['1', 9, ':', '0', '5', ':', '4', '5']
#expected "19:05:45"
You can convert each number in the list into a string with a for loop or list comprehension. Like so:
l = ['1', 9, ':', '0', '5', ':', '4', '5']
''.join([str(x) for x in l])
'19:05:45'
Generators are perfect in this case:
>>> l = ['1', 9, ':', '0', '5', ':', '4', '5']
>>> ''.join(str(x) for x in l)
'19:05:45'
This looks the same as a list comprehension but does not require the creation of another list instance.
Just map all the elements to string before joining.
>>> ''.join(map(str,['1', 9, ':', '0', '5', ':', '4', '5']))
'19:05:45'
You can do it in a for loop
list_str = ''
for i in l:
list_str += str(i)
Or a with a list comprehension
list_str = ''.join([str(i) for i in l])
Related
I am trying t convert a number as follows:
input -> 123456
output -> ['1','2','3','4','5','6']
The following loop does work:
number = 123456
defg = []
abc = str(number)
for i in range(len(abc)):
defg.append(abc[i])
However, when i try this in the form of a one line for loop, the output is ['None','None','None','None']
My one line loop is as follows:
number = 123456
defg = []
abc = str(number)
defg= [[].append(abc[i]) for i in range(len(abc))]
Any idea what I am doing wrong?
The answers above are concise, but I personally prefer vanilla list comprehension over map, as powerful as it is. I add this answer simply for the sake of adding diversity to the mix, showing that the same can be achieved without using map.
str_list = [abc[i] for i in range(len(abc))]
We can strive for a more Pythonic solution by avoiding direct indexing and using a simpler loop.
better_str_list = [char for char in abc]
This list comprehension is basically just a translation of the for loop you already have.
Try this:
x = 527876324
print(list(str(x))
Output
['5', '2', '7', '8', '7', '6', '3', '2', '4']
here the solution
list(map(lambda x: str(x), str(number)))
Out[13]: ['1', '2', '3', '4', '5', '6']
or you can do this
list(map(str, str(number)))
Out[13]: ['1', '2', '3', '4', '5', '6']
or this
list(str(number))
['1', '2', '3', '4', '5', '6']
duplicate you can see more here
Splitting integer in Python?
Solution
As your expection the result is
number = 123456
defg = []
abc = str(number)
[defg.append(abc[i]) for i in range(len(abc))]
print(defg)
When you run the loop the values are append to defg but it return none. you assign the None value to defg so it will show the None output
Recomanded way
You can use list metnod to convert the number to list
number = 865393410
result = list(str(number))
print(result)
If you want int in list try this
number = 865393410
result = []
for i in list(str(number)):
result.append(int(i))
print(result)
With single line loop
number = 865393410
result = []
[result.append(int(i)) for i in list(str(number))]
print(result)
The last one is recommended for you
This question already has answers here:
How to sort python list of strings of numbers
(4 answers)
Closed 2 years ago.
I tried to sort a list of string that are actually integers but i do not get the right sort value. How do i sort it in a way that it is sorted according to the integer value of string ?
a = ['10', '1', '3', '2', '5', '4']
print(sorted(a))
Output:
['1', '10', '2', '3', '4', '5']
Output wanted:
['1', '2', '3', '4', '5', '10']
We have to use the lambda as a key and make each string to int before the sorted function happens.
sorted(a,key=lambda i: int(i))
Output :
['1', '2', '3', '4', '5', '10']
More shorter way -> sorted(a,key=int). Thanks to #Mark for commenting.
So one of the ways to approach this problem is converting the list to a list integers by iterating through each element and converting them to integers and later sort it and again converting it to a list of strings again.
You could convert the strings to integers, sort them, and then convert back to strings. Example using list comprehensions:
sorted_a = [str(x) for x in sorted(int(y) for y in a)]
More verbose version:
int_a = [int(x) for x in a] # Convert all elements of a to ints
sorted_int_a = sorted(int_a) # Sort the int list
sorted_str_a = [str(x) for x in sorted_int_a] # Convert all elements of int list to str
print(sorted_str_a)
Note: #tedd's solution to this problem is the preferred solution to this problem, I would definitely recommend that over this.
Whenever you have a list of elements and you want to sort using some property of the elements, use key argument (see the docs).
Here's what it looks like:
>>> a = ['10', '1', '3', '2', '5', '4']
>>> print(sorted(a))
['1', '10', '2', '3', '4', '5']
>>> print(sorted(a, key=lambda el: int(el)))
['1', '2', '3', '4', '5', '10']
i have list like
list = ['1,2,3,4,5', '6,7,8,9,10']
I have problem with "," in list, because '1,2,3,4,5' its string.
I want to have list2 = ['1','2','3','4'...]
How i can do this?
Should be something like that:
nums = []
for str in list:
nums = nums + [int(n) for n in str.split(',')]
You can loop through and split the strings up.
list = ['1,2,3,4,5', '6,7,8,9,10']
result = []
for s in list:
result += s.split(',')
print(result)
Split each value in the original by , and then keep appending them to a new list.
l = []
for x in ['1,2,3,4,5', '6,7,8,9,10']:
l.extend(y for y in x.split(','))
print(l)
Use itertools.chain.from_iterable with map:
from itertools import chain
lst = ['1,2,3,4,5', '6,7,8,9,10']
print(list(chain.from_iterable(map(lambda x: x.split(','), lst))))
# ['1', '2', '3', '4', '5', '6', '7', '8', '9', '10']
Note that you shouldn't use list name for variables as it's a built-in.
You can also use list comprehension
li = ['1,2,3,4,5', '6,7,8,9,10']
res = [c for s in li for c in s.split(',') ]
print(res)
#['1', '2', '3', '4', '5', '6', '7', '8', '9', '10']
list2 = []
list2+=(','.join(list).split(','))
','.join(list) produces a string of '1,2,3,4,5,6,7,8,9,10'
','.join(list).split(',') produces ['1', '2', '3', '4', '5', '6', '7', '8', '9', '10']
join method is used to joined elements in a list by a delimiter. It returns a string in which the elements of sequence have been joined by ','.
split method is used to split a string into a list by a delimiter. It splits a string into an array of substrings.
# Without using loops
li = ['1,2,3,4,5', '6,7,8,9,10']
p = ",".join(li).split(",")
#['1', '2', '3', '4', '5', '6', '7', '8', '9', '10']
This question already has answers here:
How do I split a list into equally-sized chunks?
(66 answers)
Closed 5 years ago.
I frequently run into a problem where I'm trying to make a list of lists of a certain length from a string.
This is an example where I have a string, but would like to make a list of lists of length 3:
x = '123456789'
target_length = 3
new = [i for i in x]
final = [new[i:i+target_length] for i in range(0, len(x), target_length)]
print(final)
Output:
[['1', '2', '3'], ['4', '5', '6'], ['7', '8', '9']]
So, this works, but feels so clunky.
Is there a better way to combine these arguments into one line or do you think that would make the code unreadable?
If you want to do it in one line you can just create the lists inside your comprehension:
x = '123456789'
target_length = 3
[list(x[i:i+target_length]) for i in range(0, len(x), target_length)]
>> [['1', '2', '3'], ['4', '5', '6'], ['7', '8', '9']]
This does it in one line:
f2 = [[x[(j * target_length) + i] for i in range(target_length)] for j in range(target_length)]
I can't remove my whitespace in my list.
invoer = "5-9-7-1-7-8-3-2-4-8-7-9"
cijferlijst = []
for cijfer in invoer:
cijferlijst.append(cijfer.strip('-'))
I tried the following but it doesn't work. I already made a list from my string and seperated everything but the "-" is now a "".
filter(lambda x: x.strip(), cijferlijst)
filter(str.strip, cijferlijst)
filter(None, cijferlijst)
abc = [x.replace(' ', '') for x in cijferlijst]
Try that:
>>> ''.join(invoer.split('-'))
'597178324879'
If you want the numbers in string without -, use .replace() as:
>>> string_list = "5-9-7-1-7-8-3-2-4-8-7-9"
>>> string_list.replace('-', '')
'597178324879'
If you want the numbers as list of numbers, use .split():
>>> string_list.split('-')
['5', '9', '7', '1', '7', '8', '3', '2', '4', '8', '7', '9']
This looks a lot like the following question:
Python: Removing spaces from list objects
The answer being to use strip instead of replace. Have you tried
abc = x.strip(' ') for x in x