def drnl_node_labeling()

in utils.py [0:0]

• 20 lines of code
• 2 McCabe index (conditional complexity)

def drnl_node_labeling(adj, src, dst):
    # Double Radius Node Labeling (DRNL).
    src, dst = (dst, src) if src > dst else (src, dst)

    idx = list(range(src)) + list(range(src + 1, adj.shape[0]))
    adj_wo_src = adj[idx, :][:, idx]

    idx = list(range(dst)) + list(range(dst + 1, adj.shape[0]))
    adj_wo_dst = adj[idx, :][:, idx]

    dist2src = shortest_path(adj_wo_dst, directed=False, unweighted=True, indices=src)
    dist2src = np.insert(dist2src, dst, 0, axis=0)
    dist2src = torch.from_numpy(dist2src)

    dist2dst = shortest_path(adj_wo_src, directed=False, unweighted=True, indices=dst-1)
    dist2dst = np.insert(dist2dst, src, 0, axis=0)
    dist2dst = torch.from_numpy(dist2dst)

    dist = dist2src + dist2dst
    dist_over_2, dist_mod_2 = dist // 2, dist % 2

    z = 1 + torch.min(dist2src, dist2dst)
    z += dist_over_2 * (dist_over_2 + dist_mod_2 - 1)
    z[src] = 1.
    z[dst] = 1.
    z[torch.isnan(z)] = 0.

    return z.to(torch.long)