1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
// The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
/*
This is an example illustrating the use of the parallel for loop
tools from the dlib C++ Library.
*/
#include <dlib/threads.h>
#include <dlib/misc_api.h> // for dlib::sleep
#include <vector>
#include <iostream>
using namespace dlib;
using namespace std;
struct function_object
{
function_object( std::vector<int>& vect ) : vect1(vect) {}
std::vector<int>& vect1;
void operator() (long i) const
{
vect1[i] = i;
dlib::sleep(100);
}
};
int main()
{
const unsigned long num_threads = 4;
std::vector<int> vect1(10);
parallel_for(num_threads, 0, vect1.size(), function_object(vect1));
for (unsigned long i = 0; i < vect1.size(); ++i)
cout << vect1[i] << endl;
cout << "\n**************************************\n";
vect1.assign(10, -1);
parallel_for(num_threads, 1, 5, function_object(vect1));
for (unsigned long i = 0; i < vect1.size(); ++i)
cout << vect1[i] << endl;
cout << "\n**************************************\n";
// uncomment this line if your compiler supports the new C++0x lambda functions
#define COMPILER_SUPPORTS_CPP0X_LAMBDA_FUNCTIONS
#ifdef COMPILER_SUPPORTS_CPP0X_LAMBDA_FUNCTIONS
std::vector<int> vect2(10);
parallel_for(num_threads, 0, vect2.size(), [&](long i){
vect2[i] = i;
dlib::sleep(100);
});
for (unsigned long i = 0; i < vect2.size(); ++i)
cout << vect2[i] << endl;
#endif
}