timer.h

Conditional Random Fields的训练识别工具

/*
  CRF++ -- Yet Another CRF toolkit

  $Id: timer.h 1528 2006-08-07 02:39:50Z taku $;

  Copyright(C) 2005 Taku Kudo <[e-mail]>

  This is free software with ABSOLUTELY NO WARRANTY.

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or(at your option) any later version.

  This library 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
#ifndef _CRFPP_TIMER_H
#define _CRFPP_TIMER_H

#include <ctime>
#include <iostream>
#include <string>
#include <limits>

/* COPY FROM Boost::timer */

namespace CRFPP {

  class timer {
  public:
    explicit timer() { start_time_ = std::clock(); }
    void   restart() { start_time_ = std::clock(); }
    double elapsed() const
      { return  double(std::clock() - start_time_) / CLOCKS_PER_SEC; }

    double elapsed_max() const
      {
        return(double(std::numeric_limits<std::clock_t>::max())
               - double(start_time_)) / double(CLOCKS_PER_SEC);
      }

    double elapsed_min() const
      { return double(1)/double(CLOCKS_PER_SEC); }

  private:
    std::clock_t start_time_;
  };

  class progress_timer : public timer {

  public:
    explicit progress_timer( std::ostream & os = std::cout ) : os_(os) {}
    ~progress_timer()
      {
        std::istream::fmtflags old_flags = os_.setf( std::istream::fixed,
                                                     std::istream::floatfield );
        std::streamsize old_prec = os_.precision( 2 );
        os_ << elapsed() << " s\n" << std::endl;
        os_.flags( old_flags );
        os_.precision( old_prec );
      }

  private:
    std::ostream & os_;
  };
}

#endif