整数形式的字符串列表['123 121'，'42 23'，'23 23']

Question

['136 145', '136 149', '137 145', '138 145', '139 145', '142 149', '142 153', '145 153'] With my list above I want to turn the elements into ints, I know that just using [int(x) for x in mylist] will not work. So my question is how do you turn the list I have into a list of ints.

Answer 1

>>> L = ['136 145', '136 149', '137 145', '138 145', '139 145', '142 149', '142 153', '145 153']
>>> [int(y) for x in L for y in x.split()]
[136, 145, 136, 149, 137, 145, 138, 145, 139, 145, 142, 149, 142, 153, 145, 153]

Answer 2

Split the text first, then convert to int:

[map(int, elem.split()) for elem in originallist]

For Python 3, where map() returns an generator, not a list, you can nest the list comprehension:

[[int(n) for n in elem.split()] for elem in originallist]

which would work equally well under Python 2.

Quick demo:

>>> originallist = ['136 145', '136 149', '137 145', '138 145', '139 145', '142 149', '142 153', '145 153']
>>> [[int(n) for n in elem.split()] for elem in originallist]
[[136, 145], [136, 149], [137, 145], [138, 145], [139, 145], [142, 149], [142, 153], [145, 153]]

You can remove the nesting by moving the elem.split() loop to the outer list comprehension, to the end:

[int(n) for elem in originallist for n in elem.split()]

which gives:

[136, 145, 136, 149, 137, 145, 138, 145, 139, 145, 142, 149, 142, 153, 145, 153]

Answer 3

As I tend to go to great lengths to avoid nested list comprehensions (I can never remember the order), I would do something like:

from itertools import chain
x = ['136 145', '136 149', '137 145', '138 145', '139 145', '142 149', '142 153', '145 153']
gen = chain.from_iterable(elem.split() for elem in x)
integers = [int(elem) for elem in gen]

Answer 4

You can try like this,

>>> import re
>>> l=['136 145', '136 149', '137 145', '138 145', '139 145', '142 149', '142 153', '145 153']    
>>> map(int, re.findall(r'\d+',' '.join(l)))
[136, 145, 136, 149, 137, 145, 138, 145, 139, 145, 142, 149, 142, 153, 145, 153]

Answer 5

>>> L = ['136 145', '136 149', '137 145', '138 145', '139 145', '142 149', '142 153', '145 153']
>>> map(int, ' '.join(L).split())
[136, 145, 136, 149, 137, 145, 138, 145, 139, 145, 142, 149, 142, 153, 145, 153]