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¶
- -c?opt
- 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.
- -m?mfile
- 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.
- -o?strat
- Use sequential graph ordering strategy strat (see Scotch user's
manual for more information).
- -t?tfile
- 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.
- -v?verb
- 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>