pgrk

README

README

Simple command line PageRank calculator.

The input file represents a directed graph as adjacency list, where each node must be identified by an integer (translation from and to your domain must happen elsewhere).

Installation

$ go get github.com/miku/pgrk/cmd/{pgrk,pgrk-gen,pgrk-dot}

Example

Example input file:

$ cat example.in
0   1
1   2
2   3   4   5
4   2
5   1

Usage:

$ pgrk example.in 2> /dev/null | sort -k2,2 -nr
2   0.33477170103317816
1   0.20154082325712538
5   0.13963495553328562
4   0.13963495553328562
3   0.13963495553328562
0   0.0447826091098397

Options:

$ pgrk
Usage: pgrk [OPTIONS] FILE
File format: TSV (NODE OUTBOUND [OUTBOUND, ...])
  -c=0.0001: convergence criteron
  -w=0.85: walk probability

Benchmark

• Computing the pagerank of an 10,004,750 node sparse graph takes about 30s (tested on i5-3470, 4 core, 3.2GHz machine, 16G RAM).
• {"p": 0.8, "nodes": 30000000, "edges": 46735510}: 1m55.010s
• {"p": 0.8, "nodes": 50000000, "edges": 77879276}: 3m6.173s
• {"p": 0.99, "nodes": 50000000, "edges": 268891019}: 4m10.350s

Utils

Generate and visualize random directed graphs, with pgrk-gen and pgrk-dot:

$ pgrk-gen -n 30 -p 0.75 > test.in
$ cat test.in | pgrk-dot | dot -Tpdf -o test.pdf && open test.pdf
$ pgrk test.in 2> /dev/null | sort -nrk2,2 | head -5
20  0.10566870915778451
18  0.10238092345567337
6   0.10012509291487659
28  0.06610747553255986
16  0.06485242652853762

Credits

• Thomas Dimson for WikiRank