std::bernoulli_distribution
From cppreference.com
| Defined in header <random>
|
||
class bernoulli_distribution;
|
(since C++11) | |
Produces random boolean values, according to the discrete probability function. The probability of true is
- P(b|p) =⎧
⎨
⎩p, if b istrue
1 − p, if b isfalse
std::bernoulli_distribution satisfies RandomNumberDistribution.
Member types
| Member type | Definition |
result_type (C++11)
|
bool
|
param_type (C++11)
|
the type of the parameter set, see RandomNumberDistribution. |
Member functions
(C++11) |
constructs new distribution (public member function) |
(C++11) |
resets the internal state of the distribution (public member function) |
Generation | |
(C++11) |
generates the next random number in the distribution (public member function) |
Characteristics | |
(C++11) |
returns the p distribution parameter (probability of generating true) (public member function) |
(C++11) |
gets or sets the distribution parameter object (public member function) |
(C++11) |
returns the minimum potentially generated value (public member function) |
(C++11) |
returns the maximum potentially generated value (public member function) |
Non-member functions
(C++11)(C++11)(removed in C++20) |
compares two distribution objects (function) |
(C++11) |
performs stream input and output on pseudo-random number distribution (function template) |
Example
Run this code
#include <iomanip>
#include <iostream>
#include <map>
#include <random>
#include <string>
int main()
{
std::random_device rd;
std::mt19937 gen(rd());
// give "true" 1/4 of the time
// give "false" 3/4 of the time
std::bernoulli_distribution d(0.25);
std::map<bool, int> hist;
for (int n = 0; n < 10000; ++n)
++hist[d(gen)];
std::cout << std::boolalpha;
for (auto const& [key, value] : hist)
std::cout << std::setw(5) << key << ' '
<< std::string(value / 500, '*') << '\n';
}
Possible output:
false ***************
true ****
External links
| Weisstein, Eric W. "Bernoulli Distribution." From MathWorld — A Wolfram Web Resource. |