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 | |
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( expected_count_: 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 |
86 | |
87 | |
88 | |
89 | |
90 | |