how to interpret 8 neighbors as follows

Question

i would like to find 8 neighbors. In an algorithm it is written as

int Nx[] = {-1, 1, 0, 0, -1, -1, 1,  1}; //8-neighbors
int Ny[] = {0, 0, -1, 1,  1, -1, 1, -1};

how 3*3 matrix is interpreted like this?

what does it mean interpret? What kind of algorithm do you mean? — freude, Dec 25 '14 at 14:18

score 1 · Accepted Answer · answered Dec 25 '14 at 14:32

These are relative x- and y- coordinates. It becomes clearer if you convert this to coordinate pairs:

 x  y     neighbour
----------------------
-1  0     left
 1  0     right
 0 -1     bottom
 0  1     top
-1  1     left-top
-1 -1     left-bottom
 1  1     right-top
 1 -1     right-bottom

how to interpret 8 neighbors as follows

1 Answers1