1NAUTY-CUBHAMG(1) Nauty Manual NAUTY-CUBHAMG(1)
2
3
4
6 nauty-cubhamg - find hamiltonian cycles in subcubic graphs
7
9 cubhamg [-#] [-v|-V] [-n#-#|-y#-#|-i|-I|-o|-O|-x|-e|-E] [-b|-t] [infile
10 [outfile]]
11
13 cubhamg : Find hamiltonian cycles in sub-cubic graphs
14
15 infile is the name of the input file in graph6/sparse6 format
16 outfile is the name of the output file in the same format
17
18 stdin and stdout are the defaults for infile and outfile
19
20 The output file will have a header if and only if the input file
21 does.
22
23 Optional switches:
24
25 -# A parameter useful for tuning (default 100)
26
27 -v Report nonhamiltonian graphs and noncubic graphs
28
29 -V .. in addition give a cycle for the hamiltonian ones
30
31 (with -c, give count for each input)
32
33 -n#-# If the two numbers are v and i, then the i-th edge
34
35 out of vertex v is required to be not in the cycle. It must be
36 that i=1..3 and v=0..n-1.
37
38 -y#-# If the two numbers are v and i, then the i-th edge
39
40 out of vertex v is required to be in the cycle. It must be that
41 i=1..3 and v=0..n-1.
42
43 You can use any number of -n/-y switches to force edges. Out of
44 range first arguments are ignored. If -y and -n specify the
45 same edge, -y wins.
46
47 -i Test + property: for each edge e, there is a hamiltonian
48
49 cycle using e.
50
51 -I Test ++ property: for each pair of edges e,e', there is
52
53 a hamiltonian cycle which uses both e and e'.
54
55 -o Test - property: for each edge e, there is a hamiltonian
56
57 cycle avoiding e
58
59 -O Test -- property: for each pair of nonadjacent edges e,e's,
60
61 there is a hamiltonian cycle avoiding both.
62 Note that
63
64 this is trivial unless the girth is at least 5.
65
66 -x Test +- property: for each pair of edges e,e', there is
67
68 a hamiltonian cycle which uses e but avoids e'.
69
70 -e Test 3/4 property: for each edge e, at least 3 of the 4
71
72 paths of length 3 passing through e lie on hamiltonian cycles.
73
74 -E Test 3/4+ property: for each edge e failing the 3/4 property,
75
76 all three ways of joining e to the rest of the graph are hamilā
77 tonian avoiding e.
78
79 -T# Specify a timeout, being a limit on how many search tree
80
81 nodes are made.
82 If the timeout occurs, the graph is
83
84 written to the output as if it is nonhamiltonian.
85
86 -R# Specify the number of repeat attempts for each stage.
87
88 -F Analyze covering paths from 2 or 4 vertices of degree 2.
89
90 -b Require biconnectivity
91
92 -t Require triconnectivity (note: quadratic algorithm)
93
94 -c Count hamiltonian cycles, output count for each graph.
95
96 -V, -n and -y can also be used. No graphs are output.
97
98 -y, -n, -#, -R and -T are ignored for -i, -I, -x, -o, -e, -E, -F
99
100
101
102nauty 2.8.8 November 2023 NAUTY-CUBHAMG(1)