gord(1) 						       Scotch user's manual							   gord(1)

NAME

       gord - compute sparse matrix orderings of graphs

SYNOPSIS

       gord [options] [gfile] [ofile] [lfile]

DESCRIPTION

       The  gord  program  computes,  in  a sequential way, an ordering of a Scotch source graph representing the pattern of some symmetric sparse
       matrix.

       Source graph file gfile can only be a centralized graph file. The resulting ordering is stored in file ofile. Eventual logging  information
       (such  as  the  one  produced  by option -v) is sent to file lfile. When file names are not specified, data is read from standard input and
       written to standard output. Standard streams can also be explicitely represented by a dash '-'.

       When the proper libraries have been included at compile time, gord can directly handle compressed graphs,  both	as  input  and	output.  A
       stream  is  treated as compressed whenever its name is postfixed with a compressed file extension, such as in 'brol.grf.bz2' or '-.gz'. The
       compression formats which can be supported are the bzip2 format ('.bz2'), the gzip format ('.gz'), and the lzma format ('.lzma',  on  input
       only).

OPTIONS

       -copt  Choose default ordering strategy according to one or several options among:

	      b      enforce load balance as much as possible.

	      q      privilege quality over speed (default).

	      s      privilege speed over quality.

	      t      enforce safety.

       -h     Display some help.

       -mmfile
	      Save  column  block mapping data to file mfile. Mapping data specifies, for each vertex, the index of the column block to which this
	      vertex belongs.

       -ostrat
	      Use sequential graph ordering strategy strat (see Scotch user's manual for more information).

       -ttfile
	      Save partitioning tree data to file tfile. Partitioning tree data specifies, for each vertex, the index of the first vertex  of  the
	      parent  block  of  the  block to which the vertex belongs. Altogether with the mapping data provided in file mfile, it allows one to
	      rebuild the separator tree of the nested dissection process.

       -V     Display program version and copyright.

       -vverb Set verbose mode to verb. It is a set of one of more characters which can be:

	      s      strategy information.

	      t      timing information.

EXAMPLE

       Reorder matrix graph brol.grf and save the resulting ordering to file brol.ord using the default sequential graph ordering strategy:

	   $ gord brol.grf brol.ord

SEE ALSO

       dgord(1), gmk_hy(1), gtst(1).

       Scotch user's manual.

AUTHOR

       Francois Pellegrini <francois.pellegrini@labri.fr>

								 February 14, 2011							   gord(1)