.\" Text automatically generated by txt2man
.TH gord 1 "23 November 2019" "" "Scotch user's manual"
.SH NAME
\fBgord \fP- compute sparse matrix orderings of graphs
\fB
.SH SYNOPSIS
.nf
.fam C
\fBgord\fP [\fIoptions\fP] [\fIgfile\fP] [\fIofile\fP] [\fIlfile\fP]

.fam T
.fi
.fam T
.fi
.SH DESCRIPTION
The \fBgord\fP program computes, in a sequential way, an ordering of a
Scotch source graph representing the pattern of some symmetric
sparse matrix.
.PP
Source graph file \fIgfile\fP can only be a centralized graph file. The
resulting ordering is stored in file \fIofile\fP. Eventual logging
information (such as the one produced by option \fB-v\fP) is sent to file
\fIlfile\fP. 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 '-'.
.PP
When the proper libraries have been included at compile time, \fBgord\fP
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').
.SH OPTIONS
.TP
.B
\fB-c\fPopt
Choose default ordering strategy according to one or
several \fIoptions\fP among:
.RS
.TP
.B
b
enforce load balance as much as possible.
.TP
.B
q
privilege quality over speed (default).
.TP
.B
s
privilege speed over quality.
.TP
.B
t
enforce safety.
.RE
.TP
.B
\fB-h\fP
Display some help.
.TP
.B
\fB-m\fP\fImfile\fP
Save column block mapping data to file \fImfile\fP. Mapping
data specifies, for each vertex, the index of the column
block to which this vertex belongs.
.TP
.B
\fB-o\fP\fIstrat\fP
Use sequential graph ordering strategy \fIstrat\fP (see
Scotch user's manual for more information).
.TP
.B
\fB-t\fP\fItfile\fP
Save partitioning tree data to file \fItfile\fP. 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 \fImfile\fP, it allows one to rebuild the
separator tree of the nested dissection process.
.TP
.B
\fB-V\fP
Display program version and copyright.
.TP
.B
\fB-v\fP\fIverb\fP
Set verbose mode to \fIverb\fP. It is a set of one of more
characters which can be:
.RS
.TP
.B
s
strategy information.
.TP
.B
t
timing information.
.SH EXAMPLE
Reorder matrix graph brol.grf and save the resulting ordering to
file brol.ord using the default sequential graph ordering strategy:
.PP
.nf
.fam C
    $ gord brol.grf brol.ord

.fam T
.fi
.SH SEE ALSO
\fBdgord\fP(1), \fBgmk_hy\fP(1), \fBgtst\fP(1).
.PP
Scotch user's manual.
.SH AUTHOR
Francois Pellegrini <francois.pellegrini@labri.fr>