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- // timer, job_timer, and progress_display sample program -------------------//
- // Copyright Beman Dawes 1998. 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
- // 12 Jan 01 Cut time to 1.0 secs to speed regression tests (Beman Dawes)
- // 25 Sep 99 added elapsed_min() and elapsed_max() reporting
- // 16 Jul 99 Second beta
- // 6 Jul 99 Initial boost version
- #include <boost/progress.hpp>
- #include <iostream>
- #include <climits>
- using boost::timer;
- using boost::progress_timer;
- using boost::progress_display;
- using std::cout;
- using std::endl;
- int main() {
- timer t0; // used only for elapsed_max() and elapsed_min()
- cout << "timer::elapsed_min() reports " << t0.elapsed_min() << " seconds\n";
- cout << "timer::elapsed_max() reports " << t0.elapsed_max()
- << " seconds, which is " << t0.elapsed_max()/3600.0 << " hours\n";
- cout << "\nverify progress_display(0) doesn't divide by zero" << endl;
- progress_display zero( 0 ); // verify 0 doesn't divide by zero
- ++zero;
- long loops;
- timer loop_timer;
- const double time = 1.0;
- cout << "\ndetermine " << time << " second iteration count" << endl;
- for ( loops = 0; loops < LONG_MAX
- && loop_timer.elapsed() < time; ++loops ) {}
- cout << loops << " iterations"<< endl;
-
- long i;
- bool time_waster; // defeat [some] optimizers by storing result here
- progress_timer pt;
- timer t1;
- timer t4;
- timer t5;
- cout << "\nburn about " << time << " seconds" << endl;
- progress_display pd( loops );
- for ( i = loops; i--; )
- { time_waster = loop_timer.elapsed() < time; ++pd; }
- timer t2( t1 );
- timer t3;
- t4 = t3;
- t5.restart();
- cout << "\nburn about " << time << " seconds again" << endl;
- pd.restart( loops );
- for ( i = loops; i--; )
- { time_waster = loop_timer.elapsed() < time; ++pd; }
- if ( time_waster ) cout << ' '; // using time_waster quiets compiler warnings
- progress_display pd2( 50, cout, "\nLead string 1 ", "Lead string 2 ", "Lead string 3 " );
- for ( ; pd2.count() < 50; ++pd2 ) {}
- cout << "\nt1 elapsed: " << t1.elapsed() << '\n';
- cout << "t2 elapsed: " << t2.elapsed() << '\n';
- cout << "t3 elapsed: " << t3.elapsed() << '\n';
- cout << "t4 elapsed: " << t4.elapsed() << '\n';
- cout << "t5 elapsed: " << t5.elapsed() << '\n';
- cout << "t1 and t2 should report the same times (very approximately "
- << 2*time << " seconds).\n";
- cout << "t3, t4 and t5 should report about the same times,\n";
- cout << "and these should be about half the t1 and t2 times.\n";
- cout << "The following elapsed time should be slightly greater than t1."
- << endl;
- return 0;
- } // main
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