UserGuide

The goal of this page is to provide all the information necessary to run COS. You can choose to run COS with default parameters or you may want to fine tune it for optimum performance according to you computing resources.

Running COS

Run the executable cos without parameters or with a -h to get useful information about usage, command-line arguments, input and output files format, etc.

./cos -h

Usage

COS executable accepts the following command-line arguments:

./cos [-P <num_threads>] [-W <exp>] [-p] [-d] <mxcliques_file>

Where:

• -P <num_threads> Specifies the number of parallel threads to be executed. Default value is 8.
• -W <exp> Set the sliding window buffer size to 2**<exp> Bytes. Default value is 30 for a sliding window buffer size of 2**30 B = 1 GB.
• -p Specifies to use the proof-of-concept method COSpoc rather than COS. Since COS is faster than COSpoc, it is recommended to use this option only for benchmark purposes. With this option, -W is ignored.
• -h Prints the help and exits.
• -d If cos is compiled with the DEBUG macro (see [SetupAndCompile]), set the debug level. Otherwise it is ignored and a warning message is printed on stdout. This parameter can be passed from zero (no debug) to four (maximum verbosity level) times. Each time the parameter is passed, the verbosity level of the debug is increased by one.
• <mxcliques_file> A file containing a list of maximal cliques, one per line. Each maximal clique must be expressed as a whitespace-separated list of its nodes and must end with a virtual node -1. Nodes must be expressed as non-negative integer numbers. You might want to have a look at [MaximalCliquesListing] if you are looking for a program that lists all the maximal cliques and delivers as output a file in this format

Usage Examples

./cos <mxcliques_file>

Run the program with 8 parallel threads and a 1 GB sliding window buffer.

./cos -P 80 <mxcliques_file>

Run the program with 80 parallel threads.

./cos -P 80 -W 32 <mxcliques_file>

Run the program with 80 parallel threads and a 2**32 B = 4 GB sliding window buffer.

./cos -d <mxcliques_file>

Run the program with minimum debug info.

./cos -d -d -d -d <mxcliques_file>

Run the program with maximum debug info.

./cos -p <mxcliques_file>

Run the program with 8 parallel threads and a 1 GB sliding window buffer, using the proof-of-concept method COSpoc.

Output Files

For each k such that at least one k-clique community exists, a file named
k_comunities.txt is output in the current working directory.
Each line of the file has the format

<community_id>:<maximal_clique>

Where:

• <community_id> Is an integer number in the range [0, (Nk-1)], where Nk is the number of k-clique communities discovered for a given k. This integer uniquely identifies the community.
• <maximal_clique> Is a whistespace-separated list of nodes belonging to one input maximal clique, which is part of k-clique community identified by <community_id>

In addition, a summary file containing the number of maximal cliques discovered for each k is output as well. Each line of this file, named k_num_communities.txt, has the format

k     Nk

Where Nk is the number of k-clique communities discovered for a given k.