public member function
<random>

std::gamma_distribution::param

(1)
param_type param() const;
(2)
void param (const param_type& parm);
分布参数
第一个重载 (1) 返回一个包含当前与分布对象关联的参数的对象。
第二个重载 (2) 将对象 parm 中的参数关联到分布对象。

A gamma_distribution is defined by two parameters: alpha (α) and beta (β). An object of typeparam_typecarries this information, but it is meant to be used only to construct or specify the parameters for a gamma_distribution object, not to inspect the individual parameters.

To inspect the individual parameters associated to the distribution object you can use: gamma_distribution::alpha and gamma_distribution::beta.

参数

parm
An object representing the distribution's parameters, obtained by a call to member function param.
param_type是一个成员类型。

返回值

一个表示分布参数的对象。
param_type是一个成员类型。

示例

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// gamma_distribution::param
#include <iostream>
#include <random>

int main()
{
  std::default_random_engine generator;
  std::gamma_distribution<double> d1(2.0,2.0);
  std::gamma_distribution<double> d2(d1.param());

  // print two independent values:
  std::cout << d1(generator) << std::endl;
  std::cout << d2(generator) << std::endl;

  return 0;
}

可能的输出
3.02823
4.66655


复杂度

复杂度不劣于param_type's 构造函数。

另见