chrono

问题 I'm trying to make fixed time step loop with using < chrono >. This is my code: #include <iostream> #include <chrono> int main() { std::chrono::steady_clock::time_point start; const double timePerFrame = 1.0 / 60.0; double accumulator = 0.0; int i = 0; while(true) { start = std::chrono::steady_clock::now(); while(accumulator >= timePerFrame) { accumulator -= timePerFrame; std::cout << ++i << std::endl; //update(); } accumulator += std::chrono::duration_cast<std::chrono::duration<double>>(std:

问题 I am trying to write a template that will take any function and log its time and after some struggle with template syntax i have come up with below solution: template <typename Func, typename... Args> auto timeMyFunction(Func f, Args... args)-> typename std::enable_if<std::is_same<decltype(f(args...)),void>::value,void>::type { auto start = std::chrono::steady_clock::now(); f(args...); auto end = std::chrono::steady_clock::now(); std::chrono::duration<double> diff = end-start; std::cout <<

问题 Is there a definition somewhere in the standard namespace that sets forward: Months in a year Days in a week Hours in a day Minutes in an hour Seconds in a minute The struct tm has contains member variables that must be in these ranges, but I can't find the defined limits anywhere. I'm not even sure if there are locales defined where these wouldn't match the conventional set (12/7/24/60/60). Even if there aren't potential users with other range limits, I'd sure like to use a define from the

问题 This is my very first question here and I'm also a complete newbie at C++, but I'll do my best to be as specific as possible. Please tell me if I'm being to vague: I am trying to measure the time it takes for a sorting method (merge sort) to sort a given array of integers by using chrono and duration_cast. Here is the code snippet in question: auto t1 = std::chrono::high_resolution_clock::now(); mergesort(sortingArray, temp, 0, num - 1); auto t2 = std::chrono::high_resolution_clock::now();

问题 I'm trying to make a program that makes 6 numbers come out randomly. This is my .pro file QT += core gui greaterThan(QT_MAJOR_VERSION, 4): QT += widgets TARGET = Lotto TEMPLATE = app CONFIG += c++11 SOURCES += main.cpp\ mainwindow.cpp \ lottogenerator.cpp HEADERS += mainwindow.h \ lottogenerator.h FORMS += mainwindow.ui This is my .h file #ifndef LOTTOGENERATOR_H #define LOTTOGENERATOR_H #include <string> #include <random> #include <array> #include <chrono> class LottoGenerator { public:

问题 This question on sleeping forever has an answer that mentions this: std::this_thread::sleep_until( std::chrono::time_point<std::chrono::system_clock>::max()); and this: std::this_thread::sleep_for( std::chrono::system_clock::durat‌​ion::max()); Running this code on Visual C++ 2017 RC actually doesn't sleep at all. I haven't checked out the sleep_until() case, so I'm not sure what's going on there. In the sleep_for() case, the given duration seems to be converted to an absolute time by adding

问题 How can I add months to a chrono::system_clock::time_point value? Thank you! 回答1: Overview This is a very interesting question with several answers. The "correct" answer is something you must decide for your specific application. With months, you can choose to do either chronological computations or calendrical computations . A chronological computation deals with regular units of time points and time durations, such as hours, minutes and seconds. A calendrical computation deals with

问题 I'm in the process of porting some C++ code to Windows (from Linux/g++4.8.1) and I noticed that Microsoft's implementation of the duration's modulus operator is incorrect. The simple program #include <chrono> #include <iostream> using namespace std::chrono; int main(void) { std::cout << (milliseconds(1050)%seconds(1)).count() << std::endl; return 0; } when compiled with Microsoft Visual Studio 2012 gives the compilation error: error C2228: left of '.count' must have class/struct/union The

问题 std::chrono::system_clock::time_point m_BeginFrame = std::chrono::system_clock::now(); std::chrono::system_clock::time_point m_EndFrame = std::chrono::system_clock::now(); std::chrono::nanoseconds m_WorkTime = std::chrono::nanoseconds::zero(); std::chrono::nanoseconds m_WaitTime = std::chrono::nanoseconds::zero(); auto invFpsLimit = std::chrono::nanoseconds(1e9 / fpsLimit()); // main loop while (!glfwWindowShouldClose(m_pScreen->glfwWindow())) { m_WaitTime = m_BeginFrame - m_EndFrame; m

问题 I come here to ask for a fix to a situation that has been frustrating me. A lot. First of all, I'm on Windows, I use MinGW as a compiler (C++). I've been having some problems with getting a program to work with the use of cpp-netlib and SSL (trying to POST to a https site). I believe everything is in order except this one error that keeps evading me. C:\boost_1_50_0\boost_1_50_0\stage\lib\libboost_thread-mgw46-mt-1_50.a(thread.o):thread.cpp|| undefined reference to 'boost::chrono::system