How can I split this list of strings to list of lists of ints?

Question

I have a list of strings, it's like:

['25 32 49 50 61 72 78 41\n',
 '41 51 69 72 33 81 24 66\n']

I want to convert this list of strings, to a list of lists of ints. So my list would be:

[[25, 32, 49, 50, 61, 72, 78, 41], [41, 51, 69, 72, 33, 81, 24, 66]]

I've been thinking over this for a while, and couldn't find a solution. By the way, the list of strings, which I gave above, is populated using

open("file", "r").readlines()

Answer 1

use split() to split the string into list, and then use int() to convert them into integers.

using map() :

In [10]: lis=['25 32 49 50 61 72 78 41\n',
   ....:  '41 51 69 72 33 81 24 66\n']

In [11]: [map(int,x.split()) for x in lis]
Out[11]: [[25, 32, 49, 50, 61, 72, 78, 41], [41, 51, 69, 72, 33, 81, 24, 66]]

or using list comprehension:

In [14]: [[int(y) for y in x.split()] for x in lis]
Out[14]: [[25, 32, 49, 50, 61, 72, 78, 41], [41, 51, 69, 72, 33, 81, 24, 66]]

you can directly create this list from your file also, no need of readlines() :

with open("file") as f:
    lis=[map(int,line.split()) for line in f]
    print lis
...
[[25, 32, 49, 50, 61, 72, 78, 41], [41, 51, 69, 72, 33, 81, 24, 66]]

Answer 2

x = ['25 32 49 50 61 72 78 41\n', '41 51 69 72 33 81 24 66\n']    
map(lambda elem:map(int, elem.split()), x)

Answer 3

  b=[[int(x) for x in i.split()] for i in open("file", "r").readlines()]

尝试此列表理解