TRED(1) User Commands TRED(1)

NAME

tred - transitive reduction filter for directed graphs

SYNOPSIS

tred [ -ovr? ] [ files ]

DESCRIPTION

tred computes the transitive reduction of directed graphs, and prints
the resulting graphs to a file or standard output. This removes
edges implied by transitivity. Nodes and subgraphs are not otherwise
affected. The ``meaning'' and validity of the reduced graphs is
application dependent. tred is particularly useful as a preprocessor
to dot to reduce clutter in dense layouts.

Undirected graphs are silently ignored.

OPTIONS

The following options are supported:

-o FILE
Redirect output to the given file. By default, output goes to
stdout.

-v Verbose output to stderr.

-r Print information of removed edges to stderr.

-? Print usage information.

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.

BUGS

Using bitmaps internally would substantially decrease running time.

DIAGNOSTICS

If a graph has cycles, its transitive reduction is not uniquely
defined. In this case tred emits a warning.

AUTHORS

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

SEE ALSO

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

21 March 2001 TRED(1)