C ++，mpi:创建随机数据的最简单方法 [英] C++ ,mpi : easiest way to create random data

问题描述

在我的c ++ mpi项目中，我创建了函数:

In my c++ mpi project i created function:

 RandomDataInitialization(pMatrix, pVector, Size);

，并且我试图在函数RandomDataInitialization中形成矩阵A和向量b的值.所以我想问问也许有人知道最简单，最有效的方法吗?

and I am trying to form the values for matrix A and vector b in function RandomDataInitialization. So i want to ask maybe someone knows the easiest and most effective way to do this ?

推荐答案

一般而言.

c ++标准随机函数的工作方式如下:

The way c++ standard random functions work is as follows:

1. 创建一个伪随机引擎.
2. 使用随机种子对其进行初始化(其中一个很好的来源是std :: random_device)
3. 创建一个分发对象(例如Uniform_int_distribution或Unified_real_distribution)
4. 通过分布对象传递生成的伪随机数(由引擎生成)以提供随机数.

例如，要随机化数组或向量(矩阵的一种可能的存储机制):

For example, to randomise an array or vector (a likely storage mechanism for your matrix):

#include <random>
#include <array>
#include <algorithm>


int main()
{
    // a 3x3 matrix of doubles
    std::array<double, 9> matrix_data;

    // make an instance of a random device to generate one real random number
    // this is "slow" so we do it as little as possible.
    std::random_device rd {};

    // create the random engine and seed it from the random device
    auto engine = std::default_random_engine(rd());

    // create a uniform distribution generator which gives values in the range
    // 0.0 to 1.0
    auto distribution = std::uniform_real_distribution<double>(0, 1.0);

    // generate the random data by passing random numbers generated by the
    // engine through the distribution object.
    std::generate(std::begin(matrix_data), std::end(matrix_data),
                  [&distribution, &engine]
                  {
                      return distribution(engine);
                  });
}

这篇关于C ++，mpi:创建随机数据的最简单方法的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！