241 lines
7.0 KiB
Python
241 lines
7.0 KiB
Python
import os
|
|
import pickle
|
|
import random
|
|
import time
|
|
|
|
import dgl
|
|
|
|
import numpy as np
|
|
import scipy.sparse as sp
|
|
import torch
|
|
from dgl.data.utils import (
|
|
_get_dgl_url,
|
|
download,
|
|
extract_archive,
|
|
get_download_dir,
|
|
)
|
|
from torch.utils.data import DataLoader
|
|
|
|
|
|
def ReadTxtNet(file_path="", undirected=True):
|
|
"""Read the txt network file.
|
|
Notations: The network is unweighted.
|
|
|
|
Parameters
|
|
----------
|
|
file_path str : path of network file
|
|
undirected bool : whether the edges are undirected
|
|
|
|
Return
|
|
------
|
|
net dict : a dict recording the connections in the graph
|
|
node2id dict : a dict mapping the nodes to their embedding indices
|
|
id2node dict : a dict mapping nodes embedding indices to the nodes
|
|
"""
|
|
if file_path == "youtube" or file_path == "blog":
|
|
name = file_path
|
|
dir = get_download_dir()
|
|
zip_file_path = "{}/{}.zip".format(dir, name)
|
|
download(
|
|
_get_dgl_url(
|
|
os.path.join("dataset/DeepWalk/", "{}.zip".format(file_path))
|
|
),
|
|
path=zip_file_path,
|
|
)
|
|
extract_archive(zip_file_path, "{}/{}".format(dir, name))
|
|
file_path = "{}/{}/{}-net.txt".format(dir, name, name)
|
|
|
|
node2id = {}
|
|
id2node = {}
|
|
cid = 0
|
|
|
|
src = []
|
|
dst = []
|
|
weight = []
|
|
net = {}
|
|
with open(file_path, "r") as f:
|
|
for line in f.readlines():
|
|
tup = list(map(int, line.strip().split(" ")))
|
|
assert len(tup) in [
|
|
2,
|
|
3,
|
|
], "The format of network file is unrecognizable."
|
|
if len(tup) == 3:
|
|
n1, n2, w = tup
|
|
elif len(tup) == 2:
|
|
n1, n2 = tup
|
|
w = 1
|
|
if n1 not in node2id:
|
|
node2id[n1] = cid
|
|
id2node[cid] = n1
|
|
cid += 1
|
|
if n2 not in node2id:
|
|
node2id[n2] = cid
|
|
id2node[cid] = n2
|
|
cid += 1
|
|
|
|
n1 = node2id[n1]
|
|
n2 = node2id[n2]
|
|
if n1 not in net:
|
|
net[n1] = {n2: w}
|
|
src.append(n1)
|
|
dst.append(n2)
|
|
weight.append(w)
|
|
elif n2 not in net[n1]:
|
|
net[n1][n2] = w
|
|
src.append(n1)
|
|
dst.append(n2)
|
|
weight.append(w)
|
|
|
|
if undirected:
|
|
if n2 not in net:
|
|
net[n2] = {n1: w}
|
|
src.append(n2)
|
|
dst.append(n1)
|
|
weight.append(w)
|
|
elif n1 not in net[n2]:
|
|
net[n2][n1] = w
|
|
src.append(n2)
|
|
dst.append(n1)
|
|
weight.append(w)
|
|
|
|
print("node num: %d" % len(net))
|
|
print("edge num: %d" % len(src))
|
|
assert max(net.keys()) == len(net) - 1, "error reading net, quit"
|
|
|
|
sm = sp.coo_matrix((np.array(weight), (src, dst)), dtype=np.float32)
|
|
|
|
return net, node2id, id2node, sm
|
|
|
|
|
|
def net2graph(net_sm):
|
|
"""Transform the network to DGL graph
|
|
|
|
Return
|
|
------
|
|
G DGLGraph : graph by DGL
|
|
"""
|
|
start = time.time()
|
|
G = dgl.DGLGraph(net_sm)
|
|
end = time.time()
|
|
t = end - start
|
|
print("Building DGLGraph in %.2fs" % t)
|
|
return G
|
|
|
|
|
|
def make_undirected(G):
|
|
G.add_edges(G.edges()[1], G.edges()[0])
|
|
return G
|
|
|
|
|
|
def find_connected_nodes(G):
|
|
nodes = torch.nonzero(G.out_degrees(), as_tuple=False).squeeze(-1)
|
|
return nodes
|
|
|
|
|
|
class LineDataset:
|
|
def __init__(
|
|
self,
|
|
net_file,
|
|
batch_size,
|
|
num_samples,
|
|
negative=5,
|
|
gpus=[0],
|
|
fast_neg=True,
|
|
ogbl_name="",
|
|
load_from_ogbl=False,
|
|
ogbn_name="",
|
|
load_from_ogbn=False,
|
|
):
|
|
"""This class has the following functions:
|
|
1. Transform the txt network file into DGL graph;
|
|
2. Generate random walk sequences for the trainer;
|
|
3. Provide the negative table if the user hopes to sample negative
|
|
nodes according to nodes' degrees;
|
|
|
|
Parameter
|
|
---------
|
|
net_file str : path of the dgl network file
|
|
walk_length int : number of nodes in a sequence
|
|
window_size int : context window size
|
|
num_walks int : number of walks for each node
|
|
batch_size int : number of node sequences in each batch
|
|
negative int : negative samples for each positve node pair
|
|
fast_neg bool : whether do negative sampling inside a batch
|
|
"""
|
|
self.batch_size = batch_size
|
|
self.negative = negative
|
|
self.num_samples = num_samples
|
|
self.num_procs = len(gpus)
|
|
self.fast_neg = fast_neg
|
|
|
|
if load_from_ogbl:
|
|
assert (
|
|
len(gpus) == 1
|
|
), "ogb.linkproppred is not compatible with multi-gpu training."
|
|
from load_dataset import load_from_ogbl_with_name
|
|
|
|
self.G = load_from_ogbl_with_name(ogbl_name)
|
|
elif load_from_ogbn:
|
|
assert (
|
|
len(gpus) == 1
|
|
), "ogb.linkproppred is not compatible with multi-gpu training."
|
|
from load_dataset import load_from_ogbn_with_name
|
|
|
|
self.G = load_from_ogbn_with_name(ogbn_name)
|
|
else:
|
|
self.G = dgl.load_graphs(net_file)[0][0]
|
|
self.G = make_undirected(self.G)
|
|
print("Finish reading graph")
|
|
|
|
self.num_nodes = self.G.num_nodes()
|
|
|
|
start = time.time()
|
|
seeds = np.random.choice(
|
|
np.arange(self.G.num_edges()), self.num_samples, replace=True
|
|
) # edge index
|
|
self.seeds = torch.split(
|
|
torch.LongTensor(seeds),
|
|
int(np.ceil(self.num_samples / self.num_procs)),
|
|
0,
|
|
)
|
|
end = time.time()
|
|
t = end - start
|
|
print("generate %d samples in %.2fs" % (len(seeds), t))
|
|
|
|
# negative table for true negative sampling
|
|
self.valid_nodes = find_connected_nodes(self.G)
|
|
if not fast_neg:
|
|
node_degree = self.G.out_degrees(self.valid_nodes).numpy()
|
|
node_degree = np.power(node_degree, 0.75)
|
|
node_degree /= np.sum(node_degree)
|
|
node_degree = np.array(node_degree * 1e8, dtype=int)
|
|
self.neg_table = []
|
|
|
|
for idx, node in enumerate(self.valid_nodes):
|
|
self.neg_table += [node] * node_degree[idx]
|
|
self.neg_table_size = len(self.neg_table)
|
|
self.neg_table = np.array(self.neg_table, dtype=int)
|
|
del node_degree
|
|
|
|
def create_sampler(self, i):
|
|
"""create random walk sampler"""
|
|
return EdgeSampler(self.G, self.seeds[i])
|
|
|
|
def save_mapping(self, map_file):
|
|
with open(map_file, "wb") as f:
|
|
pickle.dump(self.node2id, f)
|
|
|
|
|
|
class EdgeSampler(object):
|
|
def __init__(self, G, seeds):
|
|
self.G = G
|
|
self.seeds = seeds
|
|
self.edges = torch.cat(
|
|
(self.G.edges()[0].unsqueeze(0), self.G.edges()[1].unsqueeze(0)), 0
|
|
).t()
|
|
|
|
def sample(self, seeds):
|
|
"""seeds torch.LongTensor : a batch of indices of edges"""
|
|
return self.edges[torch.LongTensor(seeds)]
|