Daniel@0: .TH TRED 1 "21 March 2001"
Daniel@0: .SH NAME
Daniel@0: tred \- transitive reduction filter for directed graphs
Daniel@0: .SH SYNOPSIS
Daniel@0: .B tred
Daniel@0: [ 
Daniel@0: .I files 
Daniel@0: ]
Daniel@0: .SH DESCRIPTION
Daniel@0: .B tred
Daniel@0: computes the transitive reduction of directed graphs,
Daniel@0: and prints the resulting graphs to standard output.
Daniel@0: This removes edges implied by transitivity.
Daniel@0: Nodes and subgraphs are not otherwise affected.
Daniel@0: The ``meaning'' and validity of the reduced graphs
Daniel@0: is application dependent.
Daniel@0: .B tred 
Daniel@0: is particularly useful as a preprocessor to 
Daniel@0: .I dot
Daniel@0: to reduce clutter in dense layouts.
Daniel@0: .PP
Daniel@0: Undirected graphs are silently ignored.
Daniel@0: .SH OPERANDS
Daniel@0: The following operand is supported:
Daniel@0: .TP 8
Daniel@0: .I files
Daniel@0: Names of files containing 1 or more graphs in dot format.
Daniel@0: If no
Daniel@0: .I files
Daniel@0: operand is specified,
Daniel@0: the standard input will be used.
Daniel@0: .SH "BUGS"
Daniel@0: Using bitmaps internally would substantially decrease running time.
Daniel@0: .SH "DIAGNOSTICS"
Daniel@0: If a graph has cycles, its transitive reduction is not uniquely defined.
Daniel@0: In this case \fItred\fP emits a warning.
Daniel@0: .SH AUTHORS
Daniel@0: Stephen C. North <north@research.att.com>
Daniel@0: .br
Daniel@0: Emden R. Gansner <erg@research.att.com>
Daniel@0: .SH "SEE ALSO"
Daniel@0: gc(1), dot(1), acyclic(1), gvpr(1), gvcolor(1), ccomps(1), sccmap(1), libgraph(3)