GVGEN

NAME

gvgen - generate graphs

SYNOPSIS

gvgen [ -dv? ] [ -in ] [ -cn ] [ -Cx,y ] [ -g[f]x,y ] [ -G[f]x,y ] [ -hn ] [ -kn ] [ -bx,y ] [ -Bx,y ] [ -mn ] [ -Mx,y ] [ -pn ] [ -rx,y ] [ -Rx ] [ -sn ] [ -Sn ] [ -Sn,d ] [ -tn ] [ -td,n ] [ -Tx,y ] [ -Tx,y,u,v ] [ -wn ] [ -nprefix ] [ -Nname ] [ -ooutfile ]

DESCRIPTION

gvgen generates a variety of simple, regularly-structured abstract graphs.

OPTIONS

The following options are supported:

-c n

Generate a cycle with n vertices and edges.

-C x,y

Generate an x by y cylinder. This will have x*y vertices and 2*x*y - y edges.

-g [f]x,y

Generate an x by y grid. If f is given, the grid is folded, with an edge attaching each pair of opposing corner vertices. This will have x*y vertices and 2*x*y - y - x edges if unfolded and 2*x*y - y - x + 2 edges if folded.

-G [f]x,y

Generate an x by y partial grid. If f is given, the grid is folded, with an edge attaching each pair of opposing corner vertices. This will have x*y vertices.

	-h n		Generate a hypercube of degree n. This will have 2ˆn vertices and n*2ˆ(n-1) edges.
	-k n		Generate a complete graph on n vertices with n*(n-1)/2 edges.

-b x,y

Generate a complete x by y bipartite graph. This will have x+y vertices and x*y edges.

-B x,y

Generate an x by y ball, i.e., an x by y cylinder with two "cap" nodes closing the ends. This will have x*y + 2 vertices and 2*x*y + y edges.

-m n

Generate a triangular mesh with n vertices on a side. This will have (n+1)*n/2 vertices and 3*(n-1)*n/2 edges.

-M x,y

Generate an x by y Moebius strip. This will have x*y vertices and 2*x*y - y edges.

-p n

Generate a path on n vertices. This will have n-1 edges.

-r x,y

Generate a random graph. The number of vertices will be the largest value of the form 2ˆn-1 less than or equal to x. Larger values of y increase the density of the graph.

	-R x		Generate a random rooted tree on x vertices.
	-s n		Generate a star on n vertices. This will have n-1 edges.
	-S n		Generate a Sierpinski graph of order n. This will have 3*(3ˆ(n-1) + 1)/2 vertices and 3ˆn edges.

-S n,d

Generate a d-dimensional Sierpinski graph of order n. At present, d must be 2 or 3. For d equal to 3, there will be 4*(4ˆ(n-1) + 1)/2 vertices and 6 * 4ˆ(n-1) edges.

-t n

Generate a binary tree of height n. This will have 2ˆn-1 vertices and 2ˆn-2 edges.

-t h,n

Generate a n-ary tree of height h.

-T x,y
-T x,y,u,v

Generate an x by y torus. This will have x*y vertices and 2*x*y edges. If u and v are given, they specify twists of that amount in the horizontal and vertical directions, respectively.

	-w n		Generate a path on n vertices. This will have n-1 edges.
	-i n		Generate n graphs of the requested type. At present, only available if the -R flag is used.

-n prefix

Normally, integers are used as node names. If prefix is specified, this will be prepended to the integer to create the name.

-N name

Use name as the name of the graph. By default, the graph is anonymous.

-o outfile

If specified, the generated graph is written into the file outfile. Otherwise, the graph is written to standard out.

	-d		Make the generated graph directed.
	-v		Verbose output.
	-?		Print usage information.

EXIT STATUS

gvgen exits with 0 on successful completion, and exits with 1 if given an ill-formed or incorrect flag, or if the specified output file could not be opened.

AUTHOR

Emden R. Gansner <erg@research.att.com>

SEE ALSO

gc(1), acyclic(1), gvpr(1), gvcolor(1), ccomps(1), sccmap(1), tred(1), libgraph(3)