prune - Prune directed graphs


   prune [ -n node ] [ -N attrspec ] [ -v ] [ -(h|?)  ] [ files ...  ]


   prune  reads  directed  graphs  in  the  same format used by dot(1) and
   removes subgraphs rooted at nodes specified on  the  command  line  via
   options.  These  nodes themselves will not be removed, but can be given
   attributes so that they can be easily located by a graph stream  editor
   such  as  gvpr(1).   prune  correctly  handles cycles, loops and multi

   Both options can  appear  multiple  times  on  the  command  line.  All
   subgraphs  rooted at the respective nodes given will then be processed.
   If a node does not exist, prune  will  skip  it  and  print  a  warning
   message  to  stderr.   If  multiple  attributes are given, they will be
   applied to all nodes that have been processed.  prune writes the result
   to the stdout.


   -n name
          Specifies name of node to prune.

   -N attrspec
          Specifies  attribute  that will be set (or changed if it exists)
          for  any  pruned  node.   attrspec  is  a  string  of  the  form

   -v     Verbose output.

   -h -?  Prints the usage and exits.


   An input graph test.gv of the form

        digraph DG {
          A -> B;
          A -> C;

          B -> D;
          B -> E;

   , processed by the command

        prune -n B test.gv

   would  produce the following output (the actual code might be formatted
   in a slightly different way).

        digraph DG {
          A -> B;
          A -> C;

   Another input graph test.gv of the form

        digraph DG {
          A -> B;
          A -> C;

          B -> D;
          B -> E;

          C -> E;

   (note the additional edge from C to E ), processed by the command

        prune -n B -N color=red test.gv

   results in

        digraph DG {
          B [color=red];
          A -> B;
          A -> C;
          C -> E;

   Node E has not been removed since its second  parent  C  is  not  being


   prune  returns  0  on  successful completion.  It returns 1 if an error


   dot(1), gvpr(1)


   Marcus Harnisch <>



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