1NAUTY-WATERCLUSTER2(1)           Nauty Manual           NAUTY-WATERCLUSTER2(1)
2
3
4

NAME

6       nauty-watercluster2 - (faster alternative to directg)
7

SYNOPSIS

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

DESCRIPTION

12              Reads  graphs  in g6 code or multicode (optional) from stdin and
13              directs them
14
15              ix: the indegree of every vertex may be at most x.
16
17              The default maximum indegree is unlimited.
18
19              oy: the outdegree of every vertex may be at most y.
20
21              The default maximum outdegree is unlimited.
22
23              S : allow that for every pair of vertices x,y at most one of the
24              edges x-->y
25
26              and y-->x may be present. By default both of them may be present
27              in the same graph.
28
29              T : Output directed graphs in T-code. This  is  a  simple  ASCII
30              output format.
31
32              Every  line  contains  one  graph. First the number of vertices,
33              then the number of directed edges and then the list of  directed
34              edges  with  the start first and the end then. E.g.: 3 2 0 1 2 1
35              means 3 vertices, 2 directed edges: 0-->1 and 2-->1
36
37              B : Output the directed graphs in a binary code. Every  item  of
38              the code is an
39
40              unsigned  char. The first unsigned char is the number nv of ver‐
41              tices. The vertices are numbered 1..nv. Then the  list  of  ver‐
42              tices  x  for  which  there is a directed edge 1->x follow. This
43              list is ended by a 0. Then the list of outgoing neighbours of  2
44              follows -- again ended with a 0, etc.  The code is complete with
45              the 0 ending the list of outgoing neighbours of nv.
46
47              Z : Output the directed graphs in digraph6 code. See formats.txt
48              for a
49
50              complete definition.
51
52              C  :  Do really construct all the directed graphs in memory, but
53              don't output
54
55              them. This is not a big difference in case of restricted in- and
56              outdegrees, because all that is done extra is that edges are di‐
57              rected instead of just keeping track  of  in-  and  out-degrees.
58              This  option  is intended only for testing purposes to test also
59              routines that are normally not used when counting.  Things  that
60              would speed up the counting also in some cases of restricted in-
61              and out-degrees -- like multiplying the possibilities of assign‐
62              ing directions to edges that can be assigned directions indepen‐
63              dent of each other (depending on the degrees of the  endvertices
64              and  overlaps)  -- are not included.  In case of not restrictive
65              bounds on the in- and out-degree it not really constructing  the
66              graphs  can  be  considerably faster. In cases of restricted in-
67              and out-degrees the only difference is that the graph isn't mod‐
68              ified.  The fact that in case of no output the graph is not mod‐
69              ified is mainly to save time for the one case of  waterclusters,
70              where  large  numbers were determined. If large numbers (without
71              output) for other cases shall be determined,  one  should  think
72              about adding the multiplication routines.
73
74              m : read multicode instead of g6 code
75
76       This  program  uses  different  labelling  routines -- all based on the
77       ideas of
78
79       G.  Brinkmann,   Generating   water   clusters   and   other   directed
80       graphs,mJournal of Mathematical Chemistry 46, 1112--1121 (2009)
81
82
83
84nauty 2.7.3                     September 2021          NAUTY-WATERCLUSTER2(1)
Impressum