grid.py 文件源码

def _select_surround(self, i, j):
        """
        Select the eight indices surrounding a given index.
        """
        return ([i - 1, i - 1, i + 0, i + 1, i + 1, i + 1, i + 0, i - 1],
                [j + 0, j + 1, j + 1, j + 1, j + 0, j - 1, j - 1, j - 1])