// Copyright (C) 2009 International Business Machines and others.
// All Rights Reserved.
// This code is published under the Eclipse Public License.
//
// Authors:  Andreas Waechter                   IBM    2009-11-13
//               (based on IpInexactTSymScalingMethod.hpp)

#ifndef __IPSLACKBASEDTSYMSCALINGMETHOD_HPP__
#define __IPSLACKBASEDTSYMSCALINGMETHOD_HPP__

#include "IpUtils.hpp"
#include "IpTSymScalingMethod.hpp"

namespace Ipopt
{

/** Class for the method for computing scaling factors for symmetric
 *  matrices in triplet format, specifically for the inexact algorithm.
 *  The scaling is only considering the current slacks.
 */
class SlackBasedTSymScalingMethod: public TSymScalingMethod
{
public:
   /** @name Constructor/Destructor */
   ///@{
   SlackBasedTSymScalingMethod()
   { }

   virtual ~SlackBasedTSymScalingMethod()
   { }
   ///@}

   virtual bool InitializeImpl(
      const OptionsList& options,
      const std::string& prefix
   );

   /** Method for computing the symmetric scaling factors, given the
    *  symmetric matrix in triplet (MA27) format.
    */
   virtual bool ComputeSymTScalingFactors(
      Index         n,
      Index         nnz,
      const Index*  airn,
      const Index*  ajcn,
      const Number* a,
      Number*       scaling_factors
   );

private:
   /**@name Default Compiler Generated Methods (Hidden to avoid
    * implicit creation/calling).  These methods are not implemented
    * and we do not want the compiler to implement them for us, so we
    * declare them private and do not define them. This ensures that
    * they will not be implicitly created/called. */
   ///@{
   /** Copy Constructor */
   SlackBasedTSymScalingMethod(
      const SlackBasedTSymScalingMethod&
   );

   /** Default Assignment Operator */
   void operator=(
      const SlackBasedTSymScalingMethod&
   );
};

} // namespace Ipopt

#endif
