#  Copyright (c) 1997-2018
#  Ewgenij Gawrilow, Michael Joswig (Technische Universitaet Berlin, Germany)
#  http://www.polymake.org
#
#  This program is free software; you can redistribute it and/or modify it
#  under the terms of the GNU General Public License as published by the
#  Free Software Foundation; either version 2, or (at your option) any
#  later version: http://www.gnu.org/licenses/gpl.txt.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#-------------------------------------------------------------------------------

object PolyhedralFan {

   # A Polytope defined by a non-empty set of [[VERTICES]] or [[POINTS]] is always [[FEASIBLE]].
   rule initial : {
      if (defined (my $ic=$this->INPUT_CONES)) {
         if($ic->rows == 0){
            my $emptySet = new Array<Set<Int>>();
            my $empty = new Matrix<Scalar>();
            my $ambient_dim= $this->lookup("FAN_AMBIENT_DIM")//0 ; 
            my $M;
            if ((defined ($M=$this->lookup("INPUT_RAYS")) && $M->cols()>0)
                || (defined ($M=$this->lookup("INPUT_LINEALITY")) && $M->cols()>0))
            {
               $ambient_dim = $M->cols();
            }
            my $repl=new Core::Object::Replacement(RAYS => $empty, LINEALITY_SPACE => $empty, MAXIMAL_CONES => $emptySet, FAN_DIM=>-1, FAN_AMBIENT_DIM=>$ambient_dim); 
            foreach my $prop (qw(INPUT_LINEALITY)) {
               if (defined (my $val=$this->lookup($prop))) {
                  $repl->attach($prop, $val);
               }
            }
            die $repl;
         }
      }
   }
   precondition : exists(INPUT_CONES);


   rule initial : {
      if($this->INPUT_CONES->cols() > $this->INPUT_RAYS->rows()){
         croak("\ninvalid input: number of rays used in INPUT_CONES exceeds number of INPUT_RAYS");
      }
   }
   precondition : exists(INPUT_CONES);
   precondition : exists(INPUT_RAYS);

}


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# mode: perl
# perl-indent-level: 3
# indent-tabs-mode:nil
# End:
