1 // timer, job_timer, and progress_display sample program -------------------//
2
3 // Copyright Beman Dawes 1998. Distributed under the Boost
4 // Software License, Version 1.0. (See accompanying file
5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6
7 // See http://www.boost.org/libs/timer for documentation.
8
9 // Revision History
10 // 12 Jan 01 Cut time to 1.0 secs to speed regression tests (Beman Dawes)
11 // 25 Sep 99 added elapsed_min() and elapsed_max() reporting
12 // 16 Jul 99 Second beta
13 // 6 Jul 99 Initial boost version
14
15 #include <boost/progress.hpp>
16 #include <iostream>
17 #include <climits>
18
19 using boost::timer;
20 using boost::progress_timer;
21 using boost::progress_display;
22 using std::cout;
23 using std::endl;
24
main()25 int main() {
26
27 timer t0; // used only for elapsed_max() and elapsed_min()
28
29 cout << "timer::elapsed_min() reports " << t0.elapsed_min() << " seconds\n";
30 cout << "timer::elapsed_max() reports " << t0.elapsed_max()
31 << " seconds, which is " << t0.elapsed_max()/3600.0 << " hours\n";
32
33 cout << "\nverify progress_display(0) doesn't divide by zero" << endl;
34 progress_display zero( 0 ); // verify 0 doesn't divide by zero
35 ++zero;
36
37 long loops;
38 timer loop_timer;
39 const double time = 1.0;
40
41 cout << "\ndetermine " << time << " second iteration count" << endl;
42 for ( loops = 0; loops < LONG_MAX
43 && loop_timer.elapsed() < time; ++loops ) {}
44 cout << loops << " iterations"<< endl;
45
46 long i;
47 bool time_waster; // defeat [some] optimizers by storing result here
48
49 progress_timer pt;
50 timer t1;
51 timer t4;
52 timer t5;
53
54 cout << "\nburn about " << time << " seconds" << endl;
55 progress_display pd( loops );
56 for ( i = loops; i--; )
57 { time_waster = loop_timer.elapsed() < time; ++pd; }
58
59 timer t2( t1 );
60 timer t3;
61 t4 = t3;
62 t5.restart();
63
64 cout << "\nburn about " << time << " seconds again" << endl;
65 pd.restart( loops );
66 for ( i = loops; i--; )
67 { time_waster = loop_timer.elapsed() < time; ++pd; }
68
69 if ( time_waster ) cout << ' '; // using time_waster quiets compiler warnings
70 progress_display pd2( 50, cout, "\nLead string 1 ", "Lead string 2 ", "Lead string 3 " );
71 for ( ; pd2.count() < 50; ++pd2 ) {}
72
73 cout << "\nt1 elapsed: " << t1.elapsed() << '\n';
74 cout << "t2 elapsed: " << t2.elapsed() << '\n';
75 cout << "t3 elapsed: " << t3.elapsed() << '\n';
76 cout << "t4 elapsed: " << t4.elapsed() << '\n';
77 cout << "t5 elapsed: " << t5.elapsed() << '\n';
78 cout << "t1 and t2 should report the same times (very approximately "
79 << 2*time << " seconds).\n";
80 cout << "t3, t4 and t5 should report about the same times,\n";
81 cout << "and these should be about half the t1 and t2 times.\n";
82 cout << "The following elapsed time should be slightly greater than t1."
83 << endl;
84 return 0;
85 } // main
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