Python更改数组中的元素

Python change element in array

提问by Kenenbek Arzymatov

How I can change element in array? I have this code, but I expected that it would print [[5,5],[1,4]]. But it wouldn't. It still prints [[1,2],[1,4]].

如何更改数组中的元素？我有这个代码，但我希望它会打印[[5,5],[1,4]]. 但它不会。它仍然打印[[1,2],[1,4]].

x = [[1,2], [1,4]]
for element in x:
    if element[1] == 2:
        element = [5,5]
print x

采纳答案by falsetru

Change a list element requires an index.

更改列表元素需要索引。

list_object[index] = new_value

Using enumerate, you can iterate the list and get a indexes.

使用enumerate，您可以迭代列表并获取索引。

>>> x = [[1,2], [1,4]]
>>> for i, element in enumerate(x):
...     if element[1] == 2:
...         x[i] = [5,5]
...
>>> x
[[5, 5], [1, 4]]