How to change an element in 2D array by its index without changing others in Python? [Encountered error that will change other elements]

Asked Feb 22 '22 at 04:04

Active Feb 22 '22 at 04:13

Viewed 23 times

fullOfBombsCol = ["O"] * 6
fullOfBombs = [fullOfBombsCol] * 7
fullOfBombs[1][5] = 'x'

The result I get is :
[['O', 'O', 'O', 'O', 'O', 'x'],
['O', 'O', 'O', 'O', 'O', 'x'],
['O', 'O', 'O', 'O', 'O', 'x'],
['O', 'O', 'O', 'O', 'O', 'x'],
['O', 'O', 'O', 'O', 'O', 'x'],
['O', 'O', 'O', 'O', 'O', 'x'],
['O', 'O', 'O', 'O', 'O', 'x']]
which is not what I want to as I only want to change the last element of the second array in the array.
Would appreciate if anyone can help! Thanks!

asked Feb 22 '22 at 04:04

renW

1

One way to make your array that avoids this shallow copy issue is to take `fullOfBombs = [["O" for _ in range(6)] for _ in range(7)]` – Ben Grossmann Feb 22 '22 at 04:17
1

@BenGrossmann That makes it looks like one still doesn't understand it and is now just too afraid to use `['O'] * 6` :-P – Kelly Bundy Feb 22 '22 at 04:40
1

@Kelly I can see that, maybe `[[‘O’]*6 for _ in range(7)]` is better – Ben Grossmann Feb 22 '22 at 05:41

How to change an element in 2D array by its index without changing others in Python? [Encountered error that will change other elements]

0 Answers0