python - 如何将字符串列表转换为int列表

Question

我在一个列表中有这个列表

a = [['1','2','3','4'],['1','2','3','4'],['1','2','3','4']]

但我需要它是 int ，我不确定在哪里使用 int() 将 str 更改为 int

a = [[1,2,3,4],[1,2,3,4],[1,2,3,4]]

Answer 1

您可以像这样使用嵌套列表推导：

a = [['1','2','3','4'],['1','2','3','4'],['1','2','3','4']]
b = [ [int(j) for j in i] for i in a]

Answer 2

In [51]: a = [['1','2','3','4'],['1','2','3','4'],['1','2','3','4']]

In [52]: [map(int, l) for l in a]
Out[52]: [[1, 2, 3, 4], [1, 2, 3, 4], [1, 2, 3, 4]]

Answer 3

使用嵌套列表理解的示例：

In [1]: a = [['1','2','3','4'],['1','2','3','4'],['1','2','3','4']]

In [2]: [[int(s) for s in l] for l in a]
Out[2]: [[1, 2, 3, 4], [1, 2, 3, 4], [1, 2, 3, 4]]

Answer 4

这是一个想法：

>>> a = [['1','2','3','4'],['1','2','3','4'],['1','2','3','4']]
>>> map(lambda l: map(int, l), a)
[[1, 2, 3, 4], [1, 2, 3, 4], [1, 2, 3, 4]]