商店的boost ::计时器结果在一个变量

Question

我正在写一些某种形式和搜索算法和测试他们为大学分配，我得的CPU时间和挂钟时间在处理不同的测试中使用的量。以及个人时间。

我使用升压API来实现这一目标，我的问题是，我必须运行多个测试并拿到平均时间，但我找不到存储结果升压解决方案中的变量在我给。

这里是我的算法之一：

int CA1::binarySearch(vector<int> v, int target) 
{ 

    boost::timer::auto_cpu_timer t("%w"); 

    int top, bottom, middle; 
    top = vecSize - 1; 
    bottom = 0; 

    while (bottom <= top) 
    { 
     middle = (top + bottom)/2; 
     if (v[middle] == target) 
      return middle; 
     else if (v[middle] > target) 
      top = middle - 1; 
     else 
      bottom = middle + 1; 
    } 
     return -1; 
} 

编辑

@Surt心中已经想实现你的代码如下：

int main() 
{ 
    int size = 0; 
    cout << " enter the size of your vector\n"; 
    cin >> size; 
    CA1 ca1(size); 
    ca1.DoTests; 

    system("pause"); 
    return 0; 
} 

int CA1::binarySearch(vector<int> v, int target) 
{ 

    int top, bottom, middle; 
    top = vecSize - 1; 
    bottom = 0; 

    while (bottom <= top) 
    { 
     middle = (top + bottom)/2; 
     if (v[middle] == target) 
      return middle; 
     else if (v[middle] > target) 
      top = middle - 1; 
     else 
      bottom = middle + 1; 
    } 
     return -1; 
} 

double measure(std::function<void()> function) { 
    auto start_time = std::chrono::high_resolution_clock::now(); 

    function(); 

    auto duration = std::chrono::duration_cast<std::chrono::nanoseconds> 
     (std::chrono::high_resolution_clock::now() - start_time); 
    //std::cout << test << " " << static_cast<double>(duration.count()) * 0.000001 << 
    //   " ms" << std::endl; 
    return static_cast<double>(duration.count()) * 0.000001; 
} 

void CA1::DoTests() { 
    double time = measure(CA1::binarySearch(vectorUnordered,2)); 

    cout << time << endl; 
} 

但我发现了错误抛出，

error C3867: 'CA1::DoTests': function call missing argument list; use '&CA1::DoTests' to create a pointer to member 

functional(228) : see reference to function template instantiation '_Ret std::_Callable_obj<int,false>::_ApplyX<_Rx,>(void)' being compiled 

任何想法，我哪里出错了？

编辑2

@Rob肯尼迪

我试图执行代码的std ::绑定，但我不能让我的头周围， 我已经改变了我的代码如下：

double CA1::measure(std::function<void()> function) { 
    auto startCpu = boost::chrono::process_real_cpu_clock::now(); 
    auto startWall = boost::chrono::process_system_cpu_clock::now(); 

    function(); 

    auto durationCpu = boost::chrono::duration_cast<boost::chrono::nanoseconds> 
     (boost::chrono::process_real_cpu_clock::now() - startCpu); 
    auto durationWall = boost::chrono::duration_cast<boost::chrono::nanoseconds> 
     (boost::chrono::process_system_cpu_clock::now() - startWall); 


    double cpuTime = static_cast<double>(durationCpu.count()) * 0.000001; 
    double wallTime = static_cast<double>(durationWall.count()) * 0.000001; 

    /*return static_cast<double>(duration.count()) * 0.000001;*/ 

    cout << "Cpu time " << cpuTime << endl; 
    cout << "Wall time " << wallTime << endl; 

    return cpuTime; 
} 


void CA1::DoTests() { 

    auto time = measure(std::bind(binarySearch, vectorUnordered, 2)); 
} 

错误抛出：

error C3867: 'CA1::binarySearch': function call missing argument list; use '&CA1::binarySearch' to create a pointer to member 

我把std :: bind放在正确的地方吗？我是否需要更改measure（）中的参数？ 它到底在做什么？

Answer 1

你使用boost::timer::auto_cpu_timer而是应该选用boost::timer::cpu_timer血淋淋的细节here

为了方便测量使用这样的事情，只是在std交换自己喜欢的定时器功能::计时细节：

double measure(std::function<void()> function) { 
    auto start_time = std::chrono::high_resolution_clock::now(); 

    function(); 

    auto duration = std::chrono::duration_cast<std::chrono::nanoseconds> 
        (std::chrono::high_resolution_clock::now() - start_time); 

    return static_cast<double>(duration.count()) * 0.000001; 
} 

void Test1() { 
    ... setup test 
    ... call test 
    ... validate return 
} 

void DoTests() { 
    double time = measure(Test1); 
    ... 
    ... profit! 
}