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

6       gord - compute sparse matrix orderings of graphs
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SYNOPSIS

9       gord [options] [gfile] [ofile] [lfile]
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DESCRIPTION

13       The gord program computes, in a sequential way, an ordering of a Scotch
14       source graph representing the pattern of some symmetric sparse matrix.
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16       Source graph file gfile can only be a centralized graph file.  The  re‐
17       sulting  ordering is stored in file ofile. Eventual logging information
18       (such as the one produced by option -v) is sent  to  file  lfile.  When
19       file  names  are  not  specified,  data is read from standard input and
20       written to standard output. Standard streams can  also  be  explicitely
21       represented by a dash '-'.
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23       When  the proper libraries have been included at compile time, gord can
24       directly handle compressed graphs, both as input and output.  A  stream
25       is  treated  as  compressed  whenever its name is postfixed with a com‐
26       pressed file extension, such as in 'brol.grf.bz2' or '-.gz'.  The  com‐
27       pression  formats which can be supported are the bzip2 format ('.bz2'),
28       the gzip format ('.gz'), and the lzma format ('.lzma').
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OPTIONS

31       -copt  Choose default ordering strategy according to one or several op‐
32              tions among:
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34              b      enforce load balance as much as possible.
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36              q      privilege quality over speed (default).
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38              s      privilege speed over quality.
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40              t      enforce safety.
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42       -h     Display some help.
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44       -mmfile
45              Save column block mapping data to file mfile. Mapping data spec‐
46              ifies, for each vertex, the index of the column block  to  which
47              this vertex belongs.
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49       -ostrat
50              Use  sequential graph ordering strategy strat (see Scotch user's
51              manual for more information).
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53       -ttfile
54              Save partitioning tree data to  file  tfile.  Partitioning  tree
55              data  specifies,  for each vertex, the index of the first vertex
56              of the parent block of the block to which  the  vertex  belongs.
57              Altogether  with the mapping data provided in file mfile, it al‐
58              lows one to rebuild the separator tree of the nested  dissection
59              process.
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61       -V     Display program version and copyright.
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63       -vverb Set  verbose mode to verb. It is a set of one of more characters
64              which can be:
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66              s      strategy information.
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68              t      timing information.
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EXAMPLE

71       Reorder matrix graph brol.grf and save the resulting ordering  to  file
72       brol.ord using the default sequential graph ordering strategy:
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74           $ gord brol.grf brol.ord
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SEE ALSO

78       dgord(1), gmk_hy(1), gtst(1).
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80       Scotch user's manual.
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AUTHOR

83       Francois Pellegrini <francois.pellegrini@labri.fr>
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87                               23 November 2019                        gord(1)
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