Clemence Magnien 
April 2015
http://www-rp.lip6.fr/~magnien/TemporalCentrality
clemence.magnien@lip6.fr

This README file describes succintly the program computing
the temporal closeness of a node in a dynamic network,
provided at the webpage above.

The program is a main C source file 'closeness.c'
It is provided 'as is' with no warranty.
You may use and distribute it, provided you cite the web page
above, and the paper:
 Time Evolution of the Importance of Nodes in Dynamic Networks
 Clémence Magnien and Fabien Tarissan,
 Submitted,
 2015.
(A preprint is available from the web page above.)
The program is designed for Linux/Unix systems but may be
compiled on any 'reasonable' platform. See below.

Please write us an e-mail if you find it useful, if you find
some bugs or have any idea to improve it.


* QUICKSTART *
**************
1. Compile the program:

  gcc -O3 closeness.c -o closeness

2. Run it:

 ./closeness nb_nodes target_node < data_file
  for computing the closeness of node 'target_node', where
  'nb_nodes' is the total number of nodes in the network.
  Note that node ids must be numbered from 0 to node_nb - 1.

* INPUT FORMAT *
****************
The program reads plain text ; each line corresponds to a link,
given in the form 'u v t', meaning that there is a link between
u and v at time t.

IMPORTANT NOTE: the lines must be sorted by decreasing order of t.

Example :
0 1 7
0 2 5
2 3 5
3 4 1
(this network contains 5 nodes, numbered from 0 to 4, and links exist
from time step 1 (last line) to time step 7 (first line)).

* OUTPUT *
**********
The program writes the results on the standard output. Thus,
if you want to save them you should redirect it, using
typically 
 ./closeness nb_nodes target_node < data_file > result_file

The output format consists of one line per timestamp, providing
the following informations:
 - timestamp t
 - temporal closeness of target_node at time t

* PORTABILITY *
***************
The program is written in ANSI C, with standard libraries.