1NDMETIS(1)                       User Commands                      NDMETIS(1)
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NAME

6       ndmetis  -  Computes  a  fill-reducing  ordering of the vertices of the
7       graph using multilevel nested dissection.
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SYNOPSIS

10       ndmetis [options] <filename>
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DESCRIPTION

13              Required parameters
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15       filename
16              Stores the graph to be partitioned.
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18              Optional parameters
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20       -ctype=string
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22              Specifies the scheme to be used to match  the  vertices  of  the
23              graph during the coarsening.  The possible values are:
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25       rm     - Random matching
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27       shem   - Sorted heavy-edge matching [default]
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29       -iptype=string [applies only when -ptype=rb]
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31              Specifies the scheme to be used to compute the initial bisection
32              of the graph.  The possible values are:
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34       edge   - Separator from an edge cut
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36       node   - Separator from a greedy node-based strategy [default]
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38       -rtype=string
39
40              Specifies the scheme to be used for  refinement.   The  possible
41              values are:
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43       1sided
44              - 1-sided node-based refinement [default]
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46       2sided - 2-sided node-based refinement
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48       -ufactor=int
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50              Specifies  the  maximum  allowed load imbalance between the left
51              and right partitions during each bisection. The load  imbalanced
52              is  measured as the ratio of the 2*max(left,right)/(left+right),
53              where left and right are the sizes of the respective partitions.
54              A  value  of  x  indicates  that  the  allowed load imbalance is
55              1+x/1000.  Default is 200, indicating a load imbalance of 1.20.
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57       -pfactor=int
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59              Specifies the minimum degree of the vertices that  will  be  or‐
60              dered  last.  If  the  specified value is x>0, then any vertices
61              with a degree greater than 0.1*x*(average  degree)  are  removed
62              from  the graph, an ordering of the rest of the vertices is com‐
63              puted, and an overall ordering is computed by ordering  the  re‐
64              moved  vertices  at  the  end  of the overall ordering.  Default
65              value is 0, indicating that no vertices are removed
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67       -no2hop
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69              Specifies that the coarsening will not perform any 2-hop  match‐
70              ings  when  the standard matching fails to sufficiently contract
71              the graph.
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73       -nocompress
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75              Specifies that the graph should not be compressed  by  combining
76              together vertices that have identical adjacency lists.
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78       -ccorder
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80              Specifies  if the connected components of the graph should first
81              be identified and ordered separately.
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83       -niter=int
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85              Specifies the maximum number of iterations  for  the  refinement
86              algorithms at each stage of the uncoarsening process. Default is
87              10.
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89       -nseps=int
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91              Specifies the number of different separators that it  will  com‐
92              pute at each level of the nested dissection. The final separator
93              that is used is the smallest one. Default is 1.
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95       -nooutput
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97              Specifies that no ordering file should be generated.
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99       -seed=int
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101              Selects the seed of the random number generator.
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103       -dbglvl=int
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105              Selects the dbglvl.
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107       -help
108
109              Prints this message.
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113ndmetis 5.1.0                    January 2022                       NDMETIS(1)