大型 vector/数组的 C++ 未处理异常

Question

我的代码中不断出现未处理的异常，这让我很为难。

我确信这是我声明变量的方式。

基本上，我试图创建 3 个数组、M 行、N 列随机变量。如果我设置我的 N = 1,000 和 M = 10,000，这不是问题。如果我随后更改 M = 100,000，我会收到未处理的异常内存分配错误。

谁能帮我理解为什么会这样。

部分代码是在 VS2010 上编写的。我现在已经转向 VS2013，所以任何关于使用新功能的额外建议也将不胜感激。干杯，

#include <cmath>
#include <iostream>
#include <random>
#include <vector>
#include <ctime>
#include <ratio>
#include <chrono>
int main()
{
    using namespace std::chrono;

    steady_clock::time_point Start_Time = steady_clock::now();

    unsigned int N; // Number of time Steps in a simulation
    unsigned long int M; // Number of simulations (paths)

    N = 1000;
    M = 10000;
// Random Number generation setup 
    double RANDOM;
    srand((unsigned int)time(NULL)); // Generator loop reset

    std::default_random_engine generator(rand()); // Seed with RAND()

    std::normal_distribution<double> distribution(0.0, 1.0); // Mean = 0.0, Variance = 1.0 ie Normal

    std::vector<std::vector<double>> RandomVar_A(M, std::vector<double>(N)); // dw
    std::vector<std::vector<double>> RandomVar_B(M, std::vector<double>(N)); // uncorrelated dz
    std::vector<std::vector<double>> RandomVar_C(M, std::vector<double>(N)); // dz

// Generate random variables for dw
    for (unsigned long int i = 0; i < M; i++)
        {
        for (unsigned int j = 0; j < N; j++)
            {
                RANDOM = distribution(generator);
                RandomVar_A[i][j] = RANDOM;
            }
        }
// Generate random variables for uncorrelated dz
    for (unsigned long int i = 0; i < M; i++)
        {
        for (unsigned int j = 0; j < N; j++)
            {
                RANDOM = distribution(generator);
                RandomVar_B[i][j] = RANDOM;
            }
        }
// Generate random variables for dz
    for (unsigned long int i = 0; i < M; i++)
        {
        for (unsigned int j = 0; j < N; j++)
            {
                RANDOM = distribution(generator);
                RandomVar_C[i][j] = RANDOM;
            }

        }
    steady_clock::time_point End_Time = steady_clock::now();

    duration<double> time_span = duration_cast<duration<double>>(End_Time - Start_Time);
//Clear Matricies
    RandomVar_A.clear();
    RandomVar_B.clear();
    RandomVar_C.clear();

    std::cout << std::endl;
    std::cout << "its done";
    std::cout << std::endl << std::endl;
    std::cout << "Time taken :  " << time_span.count() << " Seconds" << std::endl << std::endl;
    std::cout << "End Of Program" << std::endl << std::endl;
    system("pause");
    return 0;
}
//  *************** END OF PROGRAM ***************

Answer 1

三个 100,000 x 1,000 的 double 组代表 3 亿个 double 。假设 8 字节加倍，那就是大约 2.3 GB 的内存。很可能您的进程在 Windows 上默认限制为 2 GB(即使您的机器上安装了更多的 RAM)。但是，有一些方法可以让您的进程访问更大的地址空间:Memory Limits for Windows .