問題描述

所以我有一個隨機對象:

So i have a Random object:

typedef unsigned int uint32;

class Random {
public:
    Random() = default;
    Random(std::mt19937::result_type seed) : eng(seed) {}

private:
    uint32 DrawNumber();
    std::mt19937 eng{std::random_device{}()};
    std::uniform_int_distribution<uint32> uniform_dist{0, UINT32_MAX};
};

uint32 Random::DrawNumber()
{
    return uniform_dist(eng);
}

我可以改變(通過另一個函數或其他方式)分布上限的最佳方法是什么?

What's the best way I can vary (through another function or otherwise) the upper bound of of the distribution?

(也愿意接受其他風格問題的建議)

(also willing to take advice on other style issues)

推薦答案

分發對象是輕量級的.當您需要隨機數時，只需構建一個新的分布.我在游戲引擎中使用這種方法，經過基準測試后，它可以與使用舊的 rand() 相媲美.

Distribution objects are lightweight. Simply construct a new distribution when you need a random number. I use this approach in a game engine, and, after benchmarking, it's comparable to using good old rand().

此外，我在 GoingNative 2013 直播中詢問了如何改變分發范圍，標準委員會成員 Stephen T. Lavavej 建議簡單地創建新分發，因為它不應該是表演問題.

Also, I've asked how to vary the range of distribution on GoingNative 2013 live stream, and Stephen T. Lavavej, a member of the standard committee, suggested to simply create new distributions, as it shouldn't be a performance issue.

以下是我將如何編寫您的代碼:

Here's how I would write your code:

using uint32 = unsigned int;

class Random {
public:
    Random() = default;
    Random(std::mt19937::result_type seed) : eng(seed) {}
    uint32 DrawNumber(uint32 min, uint32 max);

private:        
    std::mt19937 eng{std::random_device{}()};
};

uint32 Random::DrawNumber(uint32 min, uint32 max)
{
    return std::uniform_int_distribution<uint32>{min, max}(eng);
}

這篇關于改變uniform_int_distribution的范圍的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！