Randomness Generation

Header file: <libs/superdrops/collisions/urbg.hpp> [source]

template<class DeviceType>
struct URBG

Struct wrapping Kokkos random number generator.

Generates random numbers in the range [start, end). Result equivalent to std::uniform_int_distribution with parameters [a, b) = [start, end), where g = C++11 UniformRandomBitGenerator (URBG). Useful e.g. for using urand(start, end) function of Kokkos random number generator ‘gen’ to generate random numbers for shuffling super-droplets array by swapping elements in range [start, end), e.g, for linear sampling of super-droplet pairs in SDM collision algorithm.

Template Parameters:

DeviceType – The Kokkos device type.

Public Functions

inline uint64_t operator()(const uint64_t start, const uint64_t end)

Draws a random 64-bit unsigned integer (uint64_t) from a uniform distribution in the range [start, end).

includes start, excludes end value.

Parameters:

• start – The lower bound of the range.

• end – The upper bound of the range.

Returns:

The random 8-byte unsigned integer.

inline double drand(const double start, const double end)

Draws a random number (double) from a uniform distribution in the range [start, end).

includes start, excludes end value.

Parameters:

• start – The lower bound of the range.

• end – The upper bound of the range.

Returns:

The random double.

Public Members

Kokkos::Random_XorShift64<DeviceType> gen

Kokkos random number generator