gord - compute sparse matrix orderings of graphs
gord [options] [gfile] [ofile] [lfile]
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').
- -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.
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
dgord(1),
gmk_hy(1),
gtst(1).
Scotch user's manual.
Francois Pellegrini <
[email protected]>