Timer.h

#ifndef UTIL_TIMER_H
#define UTIL_TIMER_H
 
/*
* Util Package - C++ Utilities for Scientific Computation
*
* Copyright 2010 - 2017, The Regents of the University of Minnesota
* Distributed under the terms of the GNU General Public License.
*/
 
#include <util/global.h>
 
#ifdef UTIL_CXX11
#include <chrono>
#else
#include <ctime>
#endif
 
namespace Util
{

   class Timer
   {
   
   public:
   
      #ifdef UTIL_CXX11
      using Clock = std::chrono::steady_clock;
      using TimePoint = Clock::time_point;
      #else
      typedef clock_t TimePoint;
      #endif

      Timer();

      void start(TimePoint begin);

      void start();

      void stop(TimePoint end);
     
      void stop();
     
      void clear();

      bool isRunning() const;

      double time() const;

      static TimePoint now();
 
   private:
 
      #ifdef UTIL_CXX11
      using Duration = std::chrono::duration<double>;
      #else
      typedef double Duration;
      #endif

      Duration time_;
 
      TimePoint begin_;
 
      bool  isRunning_; 
 
   };
 
   /*
   * Stop the timer.
   */ 
   inline void Timer::stop()
   {  stop(Timer::now()); }
   
   /*
   * Is this timer running?
   */ 
   inline bool Timer::isRunning() const
   {  return isRunning_; }
 
}
#endif