Python从较大的二维列表中获取“子”二维列表？

Question

如何从较大的二维列表中获得二维子列表？

gridx = 10 
gridy = 16 

grid = [[0]*gridx for i in range(gridy)] 
subgrid = None 
# I want to get a subgrid given an x,y grid origin (bottom-left) and x,y subgrid size 

Answer 1

如果你想切片的限制X1，Y1，X2的2D名单，Y2，你可以这样做：

def getsubgrid(x1, y1, x2, y2, grid): 
    return [item[x1:x2] for item in grid[y1:y2]] 

例如：

grid = [[1, 2, 3, 4, 5, 6, 7, 8, 9], 
     [11,12,13,14,15,16,17,18,19], 
     [21,22,23,24,25,26,27,28,29], 
     [31,32,33,34,35,36,37,38,39], 
     [41,42,43,44,45,46,47,48,49], 
     [51,52,53,54,55,56,57,58,59]] 

print getsubgrid(3,2,5,4,grid) 

#prints [[24, 25], [34, 35]] 

Answer 2

我假设你的网格存储在列表中？那就是：

primary list: [ * * * * * * ] 
second item: * * * * * * 

如果是这样，你的答案就是从你的起点到你的端点遍历这些列表。

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