workshop / graph /tools.py
qiushuocheng's picture
Initial upload
a39be45 verified
import numpy as np
def edge2mat(link, num_node):
A = np.zeros((num_node, num_node))
for i, j in link:
A[j, i] = 1
return A
def normalize_digraph(A): # 除以每列的和
Dl = np.sum(A, 0)
h, w = A.shape
Dn = np.zeros((w, w))
for i in range(w):
if Dl[i] > 0:
Dn[i, i] = Dl[i] ** (-1)
AD = np.dot(A, Dn)
return AD
def get_spatial_graph(num_node, self_link, inward, outward):
I = edge2mat(self_link, num_node)
In = normalize_digraph(edge2mat(inward, num_node))
Out = normalize_digraph(edge2mat(outward, num_node))
A = np.stack((I, In, Out))
return A
import numpy as np
def get_sgp_mat(num_in, num_out, link):
A = np.zeros((num_in, num_out))
for i, j in link:
A[i, j] = 1
A_norm = A / np.sum(A, axis=0, keepdims=True)
return A_norm
def edge2mat(link, num_node):
A = np.zeros((num_node, num_node))
for i, j in link:
A[j, i] = 1
return A
def get_k_scale_graph(scale, A):
if scale == 1:
return A
An = np.zeros_like(A)
A_power = np.eye(A.shape[0])
for k in range(scale):
A_power = A_power @ A
An += A_power
An[An > 0] = 1
return An
def normalize_digraph(A):
Dl = np.sum(A, 0)
h, w = A.shape
Dn = np.zeros((w, w))
for i in range(w):
if Dl[i] > 0:
Dn[i, i] = Dl[i] ** (-1)
AD = np.dot(A, Dn)
return AD
def get_spatial_graph(num_node, self_link, inward, outward):
I = edge2mat(self_link, num_node)
In = normalize_digraph(edge2mat(inward, num_node))
Out = normalize_digraph(edge2mat(outward, num_node))
A = np.stack((I, In, Out))
return A
def normalize_adjacency_matrix(A):
node_degrees = A.sum(-1)
degs_inv_sqrt = np.power(node_degrees, -0.5)
norm_degs_matrix = np.eye(len(node_degrees)) * degs_inv_sqrt
return (norm_degs_matrix @ A @ norm_degs_matrix).astype(np.float32)
def k_adjacency(A, k, with_self=False, self_factor=1):
assert isinstance(A, np.ndarray)
I = np.eye(len(A), dtype=A.dtype)
if k == 0:
return I
Ak = np.minimum(np.linalg.matrix_power(A + I, k), 1) \
- np.minimum(np.linalg.matrix_power(A + I, k - 1), 1)
if with_self:
Ak += (self_factor * I)
return Ak
def get_multiscale_spatial_graph(num_node, self_link, inward, outward):
I = edge2mat(self_link, num_node)
A1 = edge2mat(inward, num_node)
A2 = edge2mat(outward, num_node)
A3 = k_adjacency(A1, 2)
A4 = k_adjacency(A2, 2)
A1 = normalize_digraph(A1)
A2 = normalize_digraph(A2)
A3 = normalize_digraph(A3)
A4 = normalize_digraph(A4)
A = np.stack((I, A1, A2, A3, A4))
return A
def get_adjacency_matrix(edges, num_nodes):
A = np.zeros((num_nodes, num_nodes), dtype=np.float32)
for edge in edges:
A[edge] = 1.
return A
def get_uniform_graph(num_node, self_link, neighbor):
A = normalize_digraph(edge2mat(neighbor + self_link, num_node))
return A