Machine Learning/Kaggle Social Network Contest/load data

How to load the network into networkx

There is a network analysis package for Python called networkx. This package can be installed using easy_install.

The network can be loaded using the read_edgelist function in networkx or by manually adding edges

NOTE: John found that it took up about 5.5GB of memory to load the entire network. We may need to process it in chunks - or maybe decompose it into smaller sub networks.

Method 1

import networkx as nx
DG = nx.read_edgelist('social_train.csv', create_using=nx.DiGraph(), nodetype=int, delimiter=',')

Method 2

import networkx as nx
import csv
import time

t0 = time.clock()
DG = nx.DiGraph()

netcsv = csv.reader(open('social_train.csv', 'rb'), delimiter=',')

for row in netcsv:
    tmp1 = int(row[0])
    tmp2 = int(row[1])
    DG.add_edge(tmp1, tmp2)


print "Loaded in ", str(time.clock() - t0), "s"

Below is the time to load different numbers of row using the two methods on a 2.8Ghz Quad core machine with 3GB RAM. The second method seems quicker. Note that these are just based on single loads and are intended to be a guide rather than a rigorous analysis of the methods!

Rows	1M	2M	3M
Method 1	20s	53s	103s
Method 2	15s	41s	86s