oneapi::mkl::rng::uniform (Discrete)

Generates random numbers uniformly distributed over the interval [a, b).

Description

The oneapi::mkl::rng::uniform class object is used in oneapi::mkl::rng::generate functions to provide random numbers uniformly distributed over the interval [a, b), where a, b are the left and right bounds of the interval respectively, and a, b∈Z; a < b.

The probability distribution is given by:

\[ \begin{align}\begin{aligned}P(X = k) = \frac{1}{b-a}\\k \in \{a, a + 1, \ldots, b-1\}\end{aligned}\end{align} \]

The cumulative distribution function is as follows:

\[\begin{split}F_{a, b}(x) = \begin{cases} 0, & x < a \\ \frac{x-a + 1}{b-a}, & a \leq x < b \\ 1, & x \geq b \end{cases}, x \in R\end{split}\]

API

Syntax

template<typename Method>
class uniform<std::(u)int32_t, Method> {
public:
using method_type = Method;
using result_type =  std::(u)int32_t;
uniform(): uniform((std::(u)int32_t )(0),
              std::is_same<Method,
              uniform_method::standard>::value ? (1 << 23)
              :std::numeric_limits<Type>::max()){};
explicit uniform(std::(u)int32_t a,  std::(u)int32_t b);
explicit uniform(const param_type& pt);
std::(u)int32_t a() const;
std::(u)int32_t b() const;
param_type param() const;
void param(const param_type& pt);
};

Devices supported: Host, CPU, and GPU.

Include Files

  • oneapi/mkl/rng.hpp

Template Parameters

typename Method = oneapi::mkl::rng::uniform_method::by_default

Generation method. The specific values are as follows:

oneapi::mkl::rng::uniform_method::standard

oneapi::mkl::rng::uniform_method::accurate

See brief descriptions of the methods in Distributions Template Parameter Method.

Note

The oneapi::mkl::rng::uniform_method::standard uses the s BRNG type on GPU devices. This might cause the produced numbers to have incorrect statistics (due to rounding error) when \((abs(b – a) > 2^{23} || abs(b) > 2^{23} || abs(a) > 2^{23})\). To get proper statistics for this case, use the oneapi::mkl::rng::uniform_method::accurate method instead.

Input Parameters

Name

Type

Description

a

std::int32_t

std::uint32_t

Left bound a

b

std::int32_t

std::uint32_t

Right bound b