From cppreference.com
template<classRealType=double>classuniform_real_distribution;(since C++11)Produces random floating-point values x, uniformly distributed on the interval [a, b), that is, distributed according to the probability density function:
P(x|a,b) = 1b − a.std::uniform_real_distribution satisfies all requirements of
.
Template parameters
RealType - The result type generated by the generator. The effect is undefined if this is not one of float, double, or longdouble. Member types
Member functions
constructs new distribution
(public member function)
resets the internal state of the distribution
(public member function)
Generation
generates the next random number in the distribution
(public member function)
Characteristics
returns the distribution parameters
(public member function)
gets or sets the distribution parameter object
(public member function)
returns the minimum potentially generated value
(public member function)
returns the maximum potentially generated value
(public member function)
Non-member functions
Notes
It is difficult to create a distribution over the closed interval [a, b] from this distribution. Using std::nextafter(b,std::numeric_limits<RealType>::max()) as the second parameter does not always work due to rounding error.
Most existing implementations have a bug where they may occasionally return b (
). This was originally only thought to happen when RealType is float and when
is present, but it has since been shown that
neither is required to trigger the bug
.
Example
Print 10 random numbers between 1 and 2.
Run this code
#include<iostream>#include<random>intmain(){std::random_devicerd;// Will be used to obtain a seed for the random number enginestd::mt19937gen(rd());// Standard mersenne_twister_engine seeded with rd()std::uniform_real_distribution<>dis(1.0,2.0);for(intn=0;n<10;++n)// Use dis to transform the random unsigned int generated by gen into a // double in [1, 2). Each call to dis(gen) generates a new random double.std::cout<<dis(gen)<<' ';std::cout<<'\n';}Possible output:
1.80829 1.15391 1.18483 1.38969 1.36094 1.0648 1.97798 1.27984 1.68261 1.57326 External links