/* Copyright (c) 1997-2006
   Ewgenij Gawrilow, Michael Joswig (Technische Universitaet Berlin, Germany)
   http://www.math.tu-berlin.de/polymake,  mailto:polymake@math.tu-berlin.de

   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.
*/

#ifndef _POLYMAKE_HD_EMBEDDER_H
#define _POLYMAKE_HD_EMBEDDER_H "$Project: polymake $$Id: HDEmbedder.h 7315 2006-04-02 21:37:53Z gawrilow $"

#include <HasseDiagram.h>
#include <vector>
#include <Matrix.h>
#include <argv_options.h>

namespace polymake { namespace graph {

class HDEmbedder {
protected:
   const HasseDiagram<>& HD;
   const std::vector<double>& label_width;
   int dim;
   typedef std::vector< std::vector<int> > layer_vector;
   layer_vector layers;
   double total_width, epsilon;
   std::vector<double> node_x, weights, nb_x_sum, width_in_layer;

public:
   enum { opt_primal, opt_dual, opt_eps, opt_seed, opt_next };

   HDEmbedder(const HasseDiagram<>& HD_arg, const std::vector<double>& label_width_arg)
      : HD(HD_arg), label_width(label_width_arg),
	dim(HD.dim()), layers(dim), node_x(HD.nodes()), weights(dim+1), nb_x_sum(HD.nodes()), width_in_layer(dim)
   { }

   Matrix<double> compute(const argv_option *options);

private:
   void init(const argv_option *options);

   int try_move_node(std::vector<int>::iterator n,
		     const std::vector<int>::iterator& n_first, const std::vector<int>::iterator& n_last,
		     const double delta, const double *w);

   inline void adjust_x(int node, const double x, const double *w);
   inline bool good_swap(int lnode, int rnode, const double delta, const double *w) const;
};

} }

#endif // _POLYMAKE_HD_EMBEDDER_H

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