Grouping data in a manner to export them as a CSV file

I have a messy data which seems like

10 130 31 11 106 27 12 105 31 14 100 24 15 60 24 16 70 25 17 65 18 18 60 23 20 48 21 22 28 14 24 12 18 25 2 14 26 1 10 30 0 9

I want to group them in a way that they would look like

10, 130, 31    
11, 106, 27   
12, 105, 31  
14, 100, 24  
15, 60, 24  
16, 70, 25  
...

I tried mystr.split() to end up in a list and then define the following function to group them in 3’s:

def dataframing(df):
    nd = ["["]
    a = 0
    for data in df:
        if a < 3:
            nd += str(data)
            a = a+1
        else:
            nd+= str("],[")
            a = 0
    nd  += str("]")
            
    return nd

I was pretty sure that was going to work, however, I got the following output:

['[',
 '1',
 '0',
 '1',
 '3',
 '0',
 '3',
 '1',
 ']',
 ',',
 '[',
 '1',
 '0',
 '6',
 '2',
 '7',
 '1',
 '2',
 ']',
 ',',
 '[',
 '3',
 '1',
 '1',
 '4',
 '1',
 '0',
 '0',
 ']',
 ',',
 '[',
 '1',
 '5',
 '6',
 '0',
 '2',
 '4',
 ']',
 ',',
 '[',
 '7',
 '0',
 '2',
 '5',
 '1',
 '7',
 ']',
 ',',
 '[',
 '1',
 '8',
 '1',
 '8',
 '6',
 '0',
 ']',
 ',',
 '[',
 '2',
 '0',
 '4',
 '8',
 '2',
 '1',
 ']',
 ',',
 '[',
 '2',
 '8',
 '1',
 '4',
 '2',
 '4',
 ']',
 ',',
 '[',
 '1',
 '8',
 '2',
 '5',
 '2',
 ']',
 ',',
 '[',
 '2',
 '6',
 '1',
 '1',
 '0',
 ']',
 ',',
 '[',
 '0',
 '9',
 ']']

I don’t know why but I guess my code took every figure as an individual data rather than accepting them as pieces of a number. Now I cannot advance furthermore, any alternative solutions would be graciously appreciated.

Answer

try list comprehension method. Also never use list1 += list2. Insead use list.extend() if needed.

l = "10 130 31 11 106 27 12 105 31 14 100 24 15 60 24 16 70 25 17 65 18 18 60 23 20 48 21 22 28 14 24 12 18 25 2 14 26 1 10 30 0 9"
l = l.split(" ")
l = [int(i) for i in l]

l = [10,130,31,11,106,27,12,105,31,14,100,24,15,60,24,16,70,25,17,65,18,18,60,23,20,48,21,22,28,14,24,12,18,25,2,14,26,1,10,30,0,9]

grouped = [l[i: i+4] for i in range(0,len(l), 4)]
# use 4 if you want to group in 4 or 3 if u want to group in 3
# for example to group in 3 use
# grouped = [l[i: i+3] for i in range(0,len(l), 3)]

output

[[10, 130, 31, 11],
 [106, 27, 12, 105],
 [31, 14, 100, 24],
 [15, 60, 24, 16],
 [70, 25, 17, 65],
 [18, 18, 60, 23],
 [20, 48, 21, 22],
 [28, 14, 24, 12],
 [18, 25, 2, 14],
 [26, 1, 10, 30],
 [0, 9]]