You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and dots ('.'), can be up to 35 characters long. Letters must be lowercase.
72 lines
2.6 KiB
72 lines
2.6 KiB
// boost timer.hpp header file ---------------------------------------------// |
|
|
|
// Copyright Beman Dawes 1994-99. Distributed under the Boost |
|
// Software License, Version 1.0. (See accompanying file |
|
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
|
|
|
// See http://www.boost.org/libs/timer for documentation. |
|
|
|
// Revision History |
|
// 01 Apr 01 Modified to use new <boost/limits.hpp> header. (JMaddock) |
|
// 12 Jan 01 Change to inline implementation to allow use without library |
|
// builds. See docs for more rationale. (Beman Dawes) |
|
// 25 Sep 99 elapsed_max() and elapsed_min() added (John Maddock) |
|
// 16 Jul 99 Second beta |
|
// 6 Jul 99 Initial boost version |
|
|
|
#ifndef BOOST_TIMER_HPP |
|
#define BOOST_TIMER_HPP |
|
|
|
#include <boost/config.hpp> |
|
#include <ctime> |
|
#include <boost/limits.hpp> |
|
|
|
# ifdef BOOST_NO_STDC_NAMESPACE |
|
namespace std { using ::clock_t; using ::clock; } |
|
# endif |
|
|
|
|
|
namespace boost { |
|
|
|
// timer -------------------------------------------------------------------// |
|
|
|
// A timer object measures elapsed time. |
|
|
|
// It is recommended that implementations measure wall clock rather than CPU |
|
// time since the intended use is performance measurement on systems where |
|
// total elapsed time is more important than just process or CPU time. |
|
|
|
// Warnings: The maximum measurable elapsed time may well be only 596.5+ hours |
|
// due to implementation limitations. The accuracy of timings depends on the |
|
// accuracy of timing information provided by the underlying platform, and |
|
// this varies a great deal from platform to platform. |
|
|
|
class timer |
|
{ |
|
public: |
|
timer() { _start_time = std::clock(); } // postcondition: elapsed()==0 |
|
// timer( const timer& src ); // post: elapsed()==src.elapsed() |
|
// ~timer(){} |
|
// timer& operator=( const timer& src ); // post: elapsed()==src.elapsed() |
|
void restart() { _start_time = std::clock(); } // post: elapsed()==0 |
|
double elapsed() const // return elapsed time in seconds |
|
{ return double(std::clock() - _start_time) / CLOCKS_PER_SEC; } |
|
|
|
double elapsed_max() const // return estimated maximum value for elapsed() |
|
// Portability warning: elapsed_max() may return too high a value on systems |
|
// where std::clock_t overflows or resets at surprising values. |
|
{ |
|
return (double((std::numeric_limits<std::clock_t>::max)()) |
|
- double(_start_time)) / double(CLOCKS_PER_SEC); |
|
} |
|
|
|
double elapsed_min() const // return minimum value for elapsed() |
|
{ return double(1)/double(CLOCKS_PER_SEC); } |
|
|
|
private: |
|
std::clock_t _start_time; |
|
}; // timer |
|
|
|
} // namespace boost |
|
|
|
#endif // BOOST_TIMER_HPP
|
|
|