Generate adjacency matrix given edge rule, edge rule = {{v_i, v_j} | i - j === 1 or -1 or 2 or -2 (mod 9)}

adj_matrix.py

"""
gen adjacency matrix

edge rule = {{v_i, v_j} | i - j === 1 or -1 or 2 or -2 (mod 9)}

Format
  1 2 3 4 ...
1
2
3
4
.
.
.
"""
import numpy as np


def gen_edge(v):
    """
    Given the list of vertices generate a list of sets of edges
    """
    e = []
    for i in v:
        for j in v:
            val = (i - j) % 9
            if val == 1 or val == 2:
                    e.append((i,j))
            if val == 8 or val == 7:
                    e.append((i,j))
    return e


def gen_array(e, size=9):
    """
    Generates array base on a list of set
    """
    arr = np.zeros((size, size))

    for el in e:
        i = el[0] - 1
        j = el[1] - 1

        arr[i][j] = 1

    return arr

def main():
    v = [i for i in range (1,10)]
    e = gen_edge(v)
    adj = gen_array(e)
    print(adj)


if __name__ == "__main__":
    main()