gengL - Man Page

geng [-cCmtfkbd#D#] [-kTSPF] [-uygsnh] [-lvq] [-x#X#] n [mine[:maxe]] [res/mod] [file]

Generate all graphs of a specified class.

n

: the number of vertices

mine:maxe : a range for the number of edges

#:0 means '# or more' except in the case 0:0

res/mod : only generate subset res out of subsets 0..mod-1 (see below)

-c

: only write connected graphs

-C

: only write biconnected graphs

-t

: only generate triangle-free graphs

-f

: only generate 4-cycle-free graphs

-p

: only generate 5-cycle-free graphs

-k

: only generate K4-free graphs

-T

: only generate chordal graphs

-S

: only generate split graphs

-P

: only generate perfect graphs

-F

: only generate claw-free graphs

-b

: only generate bipartite graphs

(-t, -f and -b can be used in any combination) The combination -bT gives bipartite graphs with no

induced cycles longer than 4-cycles.

-m

: save memory at the expense of time (only makes a

difference in the absence of -b, -t, -f and n <= 28).

-d#

: a lower bound for the minimum degree

-D#

: an upper bound for the maximum degree

-v

: display counts by number of edges

-l

: canonically label output graphs

-u

: do not output any graphs, just generate and count them

-g

: use graph6 output (default)

-s

: use sparse6 output

-h

: for graph6 or sparse6 format, write a header too

-q

: suppress auxiliary output (except from -v)

res/mod splitting is controlled by two parameters -X# and -x# whose default values are displayed when splitting is used. Increasing them will make the division into parts more even at the expense of more overhead, but you must use the same values for all parts. Splitting obeys the laws of modular arithmetic, for example 3/7 is the union of 3/14 and 10/14, but when subdividing like this you must manually provide the same -X and -x values to the smaller parts.