tred - transitive reduction filter for directed graphs


   tred [ files ]


   tred  computes  the transitive reduction of directed graphs, and prints
   the resulting graphs to 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.


   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.


   Using bitmaps internally would substantially decrease running time.


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


   Stephen C. North <>
   Emden R. Gansner <>


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

                             21 March 2001                         TRED(1)


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