def neighbor_sample(graph, nodes, samples):
graph_list = []
samples_list = [[25, 10, 10, 5, 5], [15, 10, 10, 5, 5]]
for idi, max_deg in enumerate(samples):
start_nodes = copy.deepcopy(nodes)
edges = []
edge_ids = []
edge_feats = []
neigh_nodes = [start_nodes]
if max_deg == -1:
pred_nodes, pred_eids = graph.predecessor(start_nodes,
return_eids=True)
else:
for idj, g_t in enumerate(graph):
pred_nodes, pred_eids = g_t.sample_predecessor(
start_nodes,
max_degree=samples_list[idi][idj],
return_eids=True)
neigh_nodes.append(pred_nodes)
for dst_node, src_nodes, src_eids in zip(
start_nodes, pred_nodes, pred_eids):
for src_node, src_eid in zip(src_nodes, src_eids):
edges.append((src_node, dst_node))
edge_ids.append(src_eid)
edge_feats.append(g_t.edge_feat['edge_type'][src_eid])
neigh_nodes = flat_node_and_edge(neigh_nodes)
from_reindex = {x: i for i, x in enumerate(neigh_nodes)}
sub_node_index = graph_kernel.map_nodes(nodes, from_reindex)
sg = subgraph(graph[0],
eid=edge_ids,
nodes=neigh_nodes,
edges=edges,
with_node_feat=False,
with_edge_feat=False)
edge_feats = np.array(edge_feats, dtype='int32')
sg._edge_feat['edge_type'] = edge_feats
graph_list.append((sg, neigh_nodes, sub_node_index))
nodes = neigh_nodes
graph_list = graph_list[::-1]
return graph_list, from_reindex
def neighbor_sample(graph, nodes, samples):
assert not graph.is_tensor(), "You must call Graph.numpy() first."
graph_list = []
for max_deg in samples:
start_nodes = copy.deepcopy(nodes)
edges = []
edge_ids = []
if max_deg == -1:
pred_nodes, pred_eids = graph.predecessor(start_nodes,
return_eids=True)
else:
pred_nodes, pred_eids = graph.sample_predecessor(
start_nodes, max_degree=max_deg, return_eids=True)
for dst_node, src_nodes, src_eids in zip(start_nodes, pred_nodes,
pred_eids):
for src_node, src_eid in zip(src_nodes, src_eids):
edges.append((src_node, dst_node))
edge_ids.append(src_eid)
neigh_nodes = [start_nodes, pred_nodes]
neigh_nodes = flat_node_and_edge(neigh_nodes)
from_reindex = {x: i for i, x in enumerate(neigh_nodes)}
sub_node_index = graph_kernel.map_nodes(nodes, from_reindex)
sg = subgraph(graph,
eid=edge_ids,
nodes=neigh_nodes,
edges=edges,
with_node_feat=False,
with_edge_feat=True)
# sg = add_self_loop(sg, sub_node_index)
graph_list.append((sg, neigh_nodes, sub_node_index))
nodes = neigh_nodes
graph_list = graph_list[::-1]
return graph_list
def graphsage_sample(graph, nodes, samples, ignore_edges=[]):
"""Implement of graphsage sample.
Reference paper: https://cs.stanford.edu/people/jure/pubs/graphsage-nips17.pdf.
Args:
graph: A pgl graph instance
nodes: Sample starting from nodes
samples: A list, number of neighbors in each layer
ignore_edges: list of edge(src, dst) will be ignored.
Return:
A list of subgraphs
"""
assert not graph.is_tensor(), "You must call Graph.numpy() first."
node_index = copy.deepcopy(nodes)
start = time.time()
num_layers = len(samples)
start_nodes = nodes
nodes = list(start_nodes)
eids, edges = [], []
nodes_set = set(nodes)
layer_nodes, layer_eids, layer_edges = [], [], []
ignore_edge_set = set([edge_hash(src, dst) for src, dst in ignore_edges])
for layer_idx in reversed(range(num_layers)):
if len(start_nodes) == 0:
layer_nodes = [nodes] + layer_nodes
layer_eids = [eids] + layer_eids
layer_edges = [edges] + layer_edges
continue
batch_pred_nodes, batch_pred_eids = graph.sample_predecessor(
start_nodes, samples[layer_idx], return_eids=True)
start = time.time()
last_nodes_set = nodes_set
nodes, eids = copy.copy(nodes), copy.copy(eids)
edges = copy.copy(edges)
nodes_set, eids_set = set(nodes), set(eids)
for srcs, dst, pred_eids in zip(batch_pred_nodes, start_nodes,
batch_pred_eids):
for src, eid in zip(srcs, pred_eids):
if edge_hash(src, dst) in ignore_edge_set:
continue
if eid not in eids_set:
eids.append(eid)
edges.append([src, dst])
eids_set.add(eid)
if src not in nodes_set:
nodes.append(src)
nodes_set.add(src)
layer_edges = [edges] + layer_edges
start_nodes = list(nodes_set - last_nodes_set)
layer_nodes = [nodes] + layer_nodes
layer_eids = [eids] + layer_eids
start = time.time()
# Find new nodes
from_reindex = {x: i for i, x in enumerate(layer_nodes[0])}
node_index = graph_kernel.map_nodes(node_index, from_reindex)
sample_index = np.array(layer_nodes[0], dtype="int64")
graph_list = []
for i in range(num_layers):
sg = subgraph(graph,
nodes=layer_nodes[0],
eid=layer_eids[i],
edges=layer_edges[i])
graph_list.append((sg, sample_index, node_index))
return graph_list