CCOMPS(1) User Commands CCOMPS(1)

NAME

ccomps - connected components filter for graphs

SYNOPSIS

ccomps [ -sxvenzC? ] [ -X[#%]s[-f] ] [ -ooutfile ] [ files ]

DESCRIPTION

ccomps decomposes graphs into their connected components, printing
the components to standard output.

OPTIONS

The following options are supported:

-e Do not induce edges in the connected components.

-s No output graph is printed. The return value can be used to
check if the graph is connected or not.

-x Only the connected components are printed, as separate graphs.

-v Counts of nodes, edges and connected components are printed.

-z Sort components by size, with the largest first. This is only
effective if either -x or -X# is present. Thus, -zX#0 will
cause the largest component to be printed.

-C Use clusters in computing components in addition to normal
edge connectivity. In essence, this gives the connected
components of the derived graph in which nodes top-level
clusters and nodes in the original graph. This maintains all
subgraph structure within a component, even if a subgraph does
not contain any nodes.

-n Do not project subgraph structure. Normally, if ccomps
produces components as graphs distinct from the input graph,
it will define subgraphs which are projections of subgraphs of
the input graph onto the component. (If the projection is
empty, no subgraph is produced.) If this flag is set, the
component contains only the relevant nodes and edges.

-X node_name
Prints only the component containing the node node_name, if
any.

-X# start

-X# start-

-X# start-last
Prints only components in the given range of indices. In the
first form, only the component whose index is start, if any,
is printed. In the second form, each component whose index is
at least start is printed. In the last form, only those
components whose indices are in the range [Istart,last] are
printed. Thus, the flag -x is equivalent to -X#0-.

-X% min

-X% min-

-X% min-max
Prints only components in the given range of sizes. In the
first form, only a component whose size is min, if any, is
printed. In the second form, each component whose size is at
least min is printed. In the last form, only those components
whose sizes are in the range [Imin,max] are printed.

-o outfile
If specified, each graph will be written to a different file
with the names derived from outfile. In particular, if both -o
and -x flags are used, then each connected component is
written to a different file. If outfile does not have a
suffix, the first file will have the name outfile; then next
outfile_1, then next outfile_2, and so on. If outfile has a
suffix, i.e., has the form base.sfx, then the files will be
named base.sfx, base_1.sfx, base_2.sfx, etc.

By default, each input graph is printed, with each connected
component given as a subgraph whose name is a concatenation of the
name of the input graph, the string "_cc_" and the number of the
component.

OPERANDS

The following operand is supported:

files Names of files containing 1 or more graphs in dot format. If
no files operand is specified, the standard input will be
used.

RETURN CODES

Unless used to extract a single connected component, ccomps returns 0
if all the input graphs are connected; and non-zero if any graph has
multiple components, or any error occurred. If just extracting a
single component, ccomps returns 0 on success and non-zero if an
error occurred.

BUGS

It is possible, though unlikely, that the names used for connected
components and their subgraphs may conflict with existing subgraph
names.

AUTHORS

Stephen C. North <north@research.att.com>
Emden R. Gansner <erg@research.att.com>

SEE ALSO

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

30 April 2011 CCOMPS(1)