Why can I not use a dictionary to change a matrix?-CodePudding

I have a dictionary that I want to use to change a matrix so I don't have to program a bunch of if statements by hand. However, the program is not recognizing it.

player_board = [["", "A", "B", "C", "D", "E", "F", "G", "H"],
                ["1", " ", " ", " ", " ", " ", " ", " ", " "],
                ["2", " ", " ", " ", " ", " ", " ", " ", " "],
                ["3", " ", " ", " ", " ", " ", " ", " ", " "],
                ["4", " ", " ", " ", " ", " ", " ", " ", " "],
                ["5", " ", " ", " ", " ", " ", " ", " ", " "],
                ["6", " ", " ", " ", " ", " ", " ", " ", " "],
                ["7", " ", " ", " ", " ", " ", " ", " ", " "],
                ["8", " ", " ", " ", " ", " ", " ", " ", " "]]
screen_encrypt = {
"A1": player_board[1][1],
"A2": player_board[2][1],
"A3": player_board[3][1],
"A4": player_board[4][1],
"A5": player_board[5][1],
"A6": player_board[6][1],
"A7": player_board[7][1],
"A8": player_board[8][1],
"B1": player_board[1][2],
"B2": player_board[2][2],
"B3": player_board[3][2],
"B4": player_board[4][2],
"B5": player_board[5][2],
"B6": player_board[6][2],
"B7": player_board[7][2],
"B8": player_board[8][2],

}

inp = "A1"
screen_encrypt[inp] = "X"

for row in player_board:
    print(row)

This is the the output:

['', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H']
['1', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['2', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['3', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['4', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['5', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['6', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['7', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['8', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']

This is the desired output:

['', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H']
['1', 'X', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['2', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['3', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['4', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['5', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['6', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['7', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['8', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']

CodePudding user response：

The issue here is that you're only changing the screen_encrypt object, rather than modifying the player_board object directly. To fix that, you could update your code to directly update the player_board instead.

For example:

player_board = [["", "A", "B", "C", "D", "E", "F", "G", "H"],
                ["1", " ", " ", " ", " ", " ", " ", " ", " "],
                ["2", " ", " ", " ", " ", " ", " ", " ", " "],
                ["3", " ", " ", " ", " ", " ", " ", " ", " "],
                ["4", " ", " ", " ", " ", " ", " ", " ", " "],
                ["5", " ", " ", " ", " ", " ", " ", " ", " "],
                ["6", " ", " ", " ", " ", " ", " ", " ", " "],
                ["7", " ", " ", " ", " ", " ", " ", " ", " "],
                ["8", " ", " ", " ", " ", " ", " ", " ", " "]]

col_header: list = player_board[0]

inp = "A1"

alpha = inp[0]
# convert string -> int
digit = int(inp[1:])

player_board[col_header.index(alpha)][digit] = 'X'

for row in player_board:
    print(row)

Output:

['', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H']
['1', 'X', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['2', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['3', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['4', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['5', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['6', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['7', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['8', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']

CodePudding user response：

Strings are called immutable, they cannot be changed. If you use a mutable object, you can change it. The simplest mutable object is a list:

player_board = [["", "A", "B", "C", "D", "E", "F", "G", "H"],
                ["1", [" "], [" "], [" "], [" "], [" "], [" "], [" "], [" "]],
                ["2", [" "], [" "], [" "], [" "], [" "], [" "], [" "], [" "]],
                ["3", [" "], [" "], [" "], [" "], [" "], [" "], [" "], [" "]],
                ["4", [" "], [" "], [" "], [" "], [" "], [" "], [" "], [" "]],
                ["5", [" "], [" "], [" "], [" "], [" "], [" "], [" "], [" "]],
                ["6", [" "], [" "], [" "], [" "], [" "], [" "], [" "], [" "]],
                ["7", [" "], [" "], [" "], [" "], [" "], [" "], [" "], [" "]],
                ["8", [" "], [" "], [" "], [" "], [" "], [" "], [" "], [" "]]

You can then say

screen_encrypt[inp][0] = "X"

Which will do what you want.

If you want to get more pythonic, you could create a Cell object:

class Cell:
    def __init__(self):
        self.value = " "
    def __str__(self):
        return self.value

player_board = [["", "A", "B", "C", "D", "E", "F", "G", "H"],
                ["1", Cell(), Cell(), Cell(), Cell(), Cell(), Cell(), Cell(), Cell()],
                ["2", Cell(), Cell(), Cell(), Cell(), Cell(), Cell(), Cell(), Cell()],
                ["3", Cell(), Cell(), Cell(), Cell(), Cell(), Cell(), Cell(), Cell()],
        #... etc

You'd then say

screen_encrypt[inp].value = "X"

You'd have to modify your display code to call str() on each cell to turn it into a nice format:

for row in player_board:
    for cell in row:
        print(str(cell), end=" ")
    print()

CodePudding user response：

You can't use a dictionary but you could use a function like this:

player_board = [["", "A", "B", "C", "D", "E", "F", "G", "H"],
                ["1", " ", " ", " ", " ", " ", " ", " ", " "],
                ["2", " ", " ", " ", " ", " ", " ", " ", " "],
                ["3", " ", " ", " ", " ", " ", " ", " ", " "],
                ["4", " ", " ", " ", " ", " ", " ", " ", " "],
                ["5", " ", " ", " ", " ", " ", " ", " ", " "],
                ["6", " ", " ", " ", " ", " ", " ", " ", " "],
                ["7", " ", " ", " ", " ", " ", " ", " ", " "],
                ["8", " ", " ", " ", " ", " ", " ", " ", " "]]

def boardUpdate(position, value, board):
    colPositions = {"A":1,"B":2,"C":3,"D":4,"E":5,"F":6,"G":7, "H":8}
    index1 = colPositions[position[0]]
    index2 = position[1]
    board[int(index1)][int(index2)] = value
    return board

result = boardUpdate("A1", "X", player_board)
for row in result:
    print(row)

Output:

['', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H']
['1', 'X', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['2', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['3', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['4', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['5', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['6', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['7', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']
['8', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ']