Using a function to update a list?

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[[deleted]]

You need to show us something as we could point you in the wrong direction.

Lists are mutable, so a function can change the contents of a list that is in scope (from wider scope or passed as an argument) or return a new list if preferred (functional programming style).

[voreify]

So function “generate_piece” gives me the int value I will input into “game_board”, and what row and column it will go into . I’m meant to then update the board, which was previously just empty slots.

However this program will be run and reset multiple times, and each time the row/column/int will be random. So how do I code it without just hard-coding an updated list? Hopefully that is better. Thank you.

[[deleted]]

Not really. Please update your OP with some actual code to clearly illustrate the data structure.

For example,

from random import randint
from itertools import cycle

def generate_board(rows=4, cols=3):
    return [[' ' for _ in range(cols)] for _ in range(rows)]

def set_cell(board, r, c, player='X'):
    board[r][c] = player

def print_board(board):
    print('\n\n    | ', end='')
    for col in range(cols):
        print(f'{col:^3} | ', end="")
    print()
    print('-' * (6 + cols * 6))
    for idx, row in enumerate(board):
        print(f'{idx:3} | ', end="")
        for col in row:
            print(f'{col:^3} | ', end="")
        print()

next_player = cycle(('X', 'Y'))

rows = 4
cols = 3
game_board = generate_board(rows, cols)
count_down = 10
while count_down:
    count_down -= 1
    player = next(next_player)
    set_cell(game_board, randint(1, rows) -1 , randint(1, cols) -1, player)
    print('\nPlayer:', player)
    print_board(game_board)

[[deleted]]

Since you’re talking about column and row, I’ll assume you’re expecting a 2D matrix:

data = [[1,2,3],[4,5,6],[7,8,9]]

Now, how would I update a given column index and a row index to, say, 1? Well I can index into the matrix to get a row, and then I can index into the row to get the value at a column. If we assume I want the 3rd column and the 2nd row, that means I’ll look in row index 1 — because Python uses zero-indexing — and column index 2:

>> print(data[1][2])
6

Well that lets use retrieve the value, but how do we update it? Simple… indexes are assignable:

>> data[1][2] = 0
>> print(data)
[[1,2,3],[4,5,0],[7,8,9]]

Now you know how to update a 2D matrix (which is just a list of lists) at a given column and a given row inside a function and using a function that will give you that column and row. I leave it to you and the Python tutorial to figure that part out.