1NAUTY-WATERCLUSTER2(1)           Nauty Manual           NAUTY-WATERCLUSTER2(1)
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NAME

6       nauty-watercluster2  -  generate  small  digraphs with given underlying
7       graph (faster alternative to directg)
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SYNOPSIS

10       watercluster2 [ix] [oy] [S] [T] [B] [Z] [C] [m]
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DESCRIPTION

13              Reads graphs in g6 code or multicode (optional) from  stdin  and
14              directs them
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16              ix: the indegree of every vertex may be at most x.
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18              The default maximum indegree is unlimited.
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20              oy: the outdegree of every vertex may be at most y.
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22              The default maximum outdegree is unlimited.
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24              S : allow that for every pair of vertices x,y at most one of the
25              edges x-->y
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27              and y-->x may be present. By default both of them may be present
28              in the same graph.
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30              T  :  Output  directed  graphs in T-code. This is a simple ASCII
31              output format.
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33              Every line contains one graph. First  the  number  of  vertices,
34              then  the number of directed edges and then the list of directed
35              edges with the start first and the end then. E.g.: 3 2 0 1  2  1
36              means 3 vertices, 2 directed edges: 0-->1 and 2-->1
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38              B  :  Output the directed graphs in a binary code. Every item of
39              the code is an
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41              unsigned char. The first unsigned char is the number nv of  ver‐
42              tices.  The  vertices  are numbered 1..nv. Then the list of ver‐
43              tices x for which there is a directed  edge  1->x  follow.  This
44              list  is ended by a 0. Then the list of outgoing neighbours of 2
45              follows -- again ended with a 0, etc.  The code is complete with
46              the 0 ending the list of outgoing neighbours of nv.
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48              Z : Output the directed graphs in digraph6 code. See formats.txt
49              for a
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51              complete definition.
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53              C : Do really construct all the directed graphs in  memory,  but
54              don't output
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56              them. This is not a big difference in case of restricted in- and
57              outdegrees, because all that is done extra is that edges are di‐
58              rected  instead  of  just  keeping track of in- and out-degrees.
59              This option is intended only for testing purposes to  test  also
60              routines  that  are normally not used when counting. Things that
61              would speed up the counting also in some cases of restricted in-
62              and out-degrees -- like multiplying the possibilities of assign‐
63              ing directions to edges that can be assigned directions indepen‐
64              dent  of each other (depending on the degrees of the endvertices
65              and overlaps) -- are not included.  In case of  not  restrictive
66              bounds  on the in- and out-degree it not really constructing the
67              graphs can be considerably faster. In cases  of  restricted  in-
68              and out-degrees the only difference is that the graph isn't mod‐
69              ified.  The fact that in case of no output the graph is not mod‐
70              ified  is mainly to save time for the one case of waterclusters,
71              where large numbers were determined. If large  numbers  (without
72              output)  for  other  cases shall be determined, one should think
73              about adding the multiplication routines.
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75              m : read multicode instead of g6 code
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77       This program uses different labelling routines  --  all  based  on  the
78       ideas of
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80       G.   Brinkmann,   Generating   water   clusters   and   other  directed
81       graphs,mJournal of Mathematical Chemistry 46, 1112--1121 (2009)
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85nauty 2.8.8                      November 2023          NAUTY-WATERCLUSTER2(1)
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