/**
 * @file   com_initialize_residual_norm.cpp
 * @author Julian Iseringhausen <isering@ins.uni-bonn.de>
 * @date   Mon Apr 18 12:40:12 2011
 *
 * @brief  Computes the residual in the discrete L2-norm
 *         and hands the value over to the factory.
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <cstdio>

#include "base/command.hpp"
#include "base/object.hpp"
#include "comm/comm.hpp"
#include "grid/multigrid.hpp"
#include "mg.hpp"

using namespace VMG;

class VMGCommandInitializeResidualNorm : public Command
{
public:
  Request Run(Command::argument_vector arguments)
  {
    vmg_float residual = MG::GetComm()->ComputeResidualNorm(*MG::GetSol(), *MG::GetRhs());
    new ObjectStorage<vmg_float>(arguments[0], residual);

    if (MG::GetComm()->Rank() == 0)
      printf("Multigrid: Initial residual: %e\n", residual);

    return Continue;
  }

  static const char* Name() {return "InitializeResidualNorm";}
  static int Arguments() {return 1;}
};

CREATE_INITIALIZER(VMGCommandInitializeResidualNorm);