[Nauty-list] genbg vs. geng

Pawel Pralat pralat at mathstat.dal.ca
Fri Jun 27 01:37:02 EST 2008

```Hi,

I needed all connected bipartite graphs on 12 vertices. I used
(fortunately?) the following

\$ ../../nauty/genbg -c 1 11 > 12_vert.txt
>A ../../nauty/genbg n=1+11 e=11:11 d=1:1 D=11:1 c
>Z 1 graphs generated in 0.00 sec
\$ ../../nauty/genbg -c 2 10 >> 12_vert.txt
>A ../../nauty/genbg n=2+10 e=11:20 d=1:1 D=10:2 c
>Z 30 graphs generated in 0.00 sec
\$ ../../nauty/genbg -c 3 9 >> 12_vert.txt
>A ../../nauty/genbg n=3+9 e=11:27 d=1:1 D=9:3 c
>Z 853 graphs generated in 0.01 sec
\$ ../../nauty/genbg -c 4 8 >> 12_vert.txt
>A ../../nauty/genbg n=4+8 e=11:32 d=1:1 D=8:4 c
>Z 14549 graphs generated in 0.07 sec
\$ ../../nauty/genbg -c 5 7 >> 12_vert.txt
>A ../../nauty/genbg n=5+7 e=11:35 d=1:1 D=7:5 c
>Z 98726 graphs generated in 0.25 sec
\$ ../../nauty/genbg -c 6 6 >> 12_vert.txt
>A ../../nauty/genbg n=6+6 e=11:36 d=1:1 D=6:6 c
>Z 194203 graphs generated in 0.36 sec
\$ cat 12_vert.txt | wc -l
308362

to get 308362 graphs but my collegue used

\$ ../../nauty/geng -cbu 12
>A ../../nauty/geng -cbd1D11 n=12 e=11-36
>Z 212780 graphs generated in 0.55 sec

and got a lot less. It seems that geng -cb does not work properly, doesn't
it?

Cheers,
-- Pawel

```