gord(1) Scotch user's manual gord(1)NAMEgord - compute sparse matrix orderings of graphs
SYNOPSISgord [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 informa‐
tion (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 com‐
pressed file extension, such as in 'brol.grf.bz2' or '-.gz'. The com‐
pression 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 spec‐
ifies, 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 dissec‐
tion 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 ALSOdgord(1), gmk_hy(1), gtst(1).
Scotch user's manual.
AUTHOR
Francois Pellegrini <francois.pellegrini@labri.fr>
February 14, 2011 gord(1)
