python - 打印二维列表的一部分

Question

我必须创建一个迷宫游戏，该游戏接收用户的命令作为输入以玩游戏。我已经编写了迷宫游戏的代码。我想要修改的是在打印给用户时(移动完成后)只显示迷宫的部分。这是我的迷宫:

level = [
    ["1"," ","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1"],
    ["1"," "," ","1","1","1","1","1","1","1"," "," "," "," "," "," "," "," "," "," ","1","1","1","1","1"],
    ["1"," "," ","1","1","1","1","1","1","1"," "," ","1","1","1","1","1","1"," "," ","1","1","1","1","1"],
    ["1"," "," "," "," "," "," "," ","1","1"," "," ","1","1","1","1","1","1"," "," ","1","1","1","1","1"],
    ["1"," "," "," "," "," "," "," ","1","1"," "," ","1","1","1"," "," "," "," "," "," "," "," ","1","1"],
    ["1"," ","1","1","1","1"," "," ","1","1"," "," ","1","1","1"," "," "," "," "," "," "," "," ","1","1"],
    ["1"," ","1","1","1","1"," "," ","1","1"," "," ","1","1","1","1","1","1"," "," ","1","1","1","1","1"],
    ["1"," ","1","1","1","1"," "," ","1","1"," "," "," "," ","1","1","1","1"," "," ","1","1","1","1","1"],
    ["1"," "," ","1","1","1"," "," "," "," "," "," "," "," ","1","1","1","1"," "," "," "," "," "," ","1"],
    ["1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1","1"," ","1"]
]

start_maze = level[0][1]      #start of maze
end_maze = level[9][23]       #end of maze

这样的输出:

The initial configuration of the maze is:
1 X 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1     1 1 1 1 1 1 1                     1 1 1 1 1
1     1 1 1 1 1 1 1     1 1 1 1 1 1     1 1 1 1 1
1               1 1     1 1 1 1 1 1     1 1 1 1 1
1               1 1     1 1 1                 1 1
1   1 1 1 1     1 1     1 1 1                 1 1
1   1 1 1 1     1 1     1 1 1 1 1 1     1 1 1 1 1
1   1 1 1 1     1 1         1 1 1 1     1 1 1 1 1
1     1 1 1                 1 1 1 1             1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1   1

我如何才能让玩家在四处移动时只能看到迷宫的一部分，而看不到尽头(这很容易做到)？

例如，要有这样的 View :

    1   1 1 1
    1     1 1 
    1   X 1 1 
    1          
    1               

即这样他在每个方向上只能看到另外 2 个细胞。

我希望我把问题说清楚了。如果需要的话，下面是主要游戏的代码部分:

player = {'y': 0, 'x': 1}
level[player['y']][player['x']] = 'X'

# Translate keywords into coordinate changes
move_modifications = {'UP': {'y': -1, 'x': 0},
                      'DOWN': {'y': 1, 'x': 0},
                      'LEFT': {'y':0, 'x': -1},
                      'RIGHT': {'y': 0, 'x': 1}} 

def player_move(maze):

    # Main game loop
    play = True
    while play:
        move = input("Please enter a command (LEFT/RIGHT/UP/DOWN): ")
        move = move.upper()

        coords = move_modifications[move]

        new_y = player['y'] + coords['y']
        new_x = player['x'] + coords['x']

        #Catch them if they try to leave the map
        try:
            maze_position = maze[new_y][new_x]
        except IndexError:
            print("Not on map")
            continue

        if maze_position != '1':
            # Move on the map
            maze[player['y']][player['x']] = ' '
            maze[new_y][new_x] = 'X'

            # Update player coords
            player['y'] = new_y
            player['x'] = new_x

            # Print result
            print_level(maze)

其余代码只是四处移动，不包括迷宫的任何打印。

Answer 1

NumPy数组可以方便地对二维列表进行切片。考虑下面的代码和切片。

# load numpy from its module
import numpy as np

# create a numpy array
np_level = np.array(level)

# slice the map
slice = np_level[max(new_y-2,0) : new_y+3, \    # y slice
                 max(new_x-2,0) : new_x+3]      # x slice

# print the slice
print(slice)
# or print_level(slice), whichever one suits your case

这需要您的二维数组 level , 创建一个 NumPy 数组 np_level , 然后从 [y-2, y+3) 范围打印它的一部分和 [x-2, x+3) (使用间隔符号)。这意味着它从 y-2 中分割数组至 y+2来自 x-2至 x+2 包容性。

max(y-2, 0)有没有万一y-2低于 0(即负)。使用负 begin-index 和正 end-index 进行切片将返回一个空列表(例如 some_array[-1:1] ==> [] )。 max(x-2, 0)也是如此.我们可以也添加min(y+3, <height-of-level>)和 min(x+3, <width-of-level>)对于 end 索引，但数组切片已经处理了这些边缘情况——所以这一切都很好。

^{注意这需要安装 NumPy 模块。如果尚未安装，请输入 python -m pip install numpy 安装它进入命令行/终端。}