Aleph::CA::Random_Asynchronous_Update< Engine_Type > Struct Template Reference

Pick one cell at random per sub-step, update it in place. More...

#include <tpl_ca_update_scheme.H>

Collaboration diagram for Aleph::CA::Random_Asynchronous_Update< Engine_Type >:

Public Member Functions
constexpr	Random_Asynchronous_Update (const std::uint64_t seed=0, const std::size_t sub_steps=0) noexcept
	Build a random asynchronous update strategy.
template<typename Engine , typename Rule >
void	apply (Engine &e, Rule &r) const
	Execute one randomised step.

Public Attributes
std::uint64_t	master_seed = 0
std::size_t	sub_steps_per_step = 0
	Number of single-cell sub-steps per step().

Static Public Attributes
static constexpr bool	requires_double_buffer = false
	In-place updates → no second buffer.
static constexpr bool	requires_block_rule = false
	Operates on cell rules.

Detailed Description

template<typename Engine_Type = std::mt19937_64>
struct Aleph::CA::Random_Asynchronous_Update< Engine_Type >

Pick one cell at random per sub-step, update it in place.

A step() performs sub_steps_per_step sub-steps; each sub-step picks a single cell uniformly at random (using the master seed, the engine step count and the sub-step index to derive a stable per-(step, sub) draw) and applies the rule in place.

Both the cell selection and any per-cell randomness in the rule derive from the same master seed but use disjoint sub-streams, so changing sub_steps_per_step reshuffles the visit pattern but keeps every other dimension reproducible.

Template Parameters

Engine_Type

PRNG used for cell selection. Defaults to std::mt19937_64 for its 64-bit output and good quality.

Definition at line 372 of file tpl_ca_update_scheme.H.

Constructor & Destructor Documentation

Random_Asynchronous_Update()

template<typename Engine_Type = std::mt19937_64>

constexpr Aleph::CA::Random_Asynchronous_Update< Engine_Type >::Random_Asynchronous_Update ( const std::uint64_t  seed = 0, const std::size_t  sub_steps = 0  )

inlineconstexprnoexcept

Build a random asynchronous update strategy.

Parameters

[in]	seed	master seed forwarded to cell_seed.
[in]	sub_steps	number of sub-steps per engine step (0 → one full sweep per step).

Exceptions

This	constructor does not throw.

Definition at line 391 of file tpl_ca_update_scheme.H.

Member Function Documentation

apply()

template<typename Engine_Type = std::mt19937_64>

template<typename Engine , typename Rule >

void Aleph::CA::Random_Asynchronous_Update< Engine_Type >::apply ( Engine &  e, Rule &  r  ) const

inline

Execute one randomised step.

Template Parameters

Engine	engine type.
Rule	cell rule satisfying RuleLike<Rule, Lattice>.

Parameters

[in,out]	e	engine reference.
[in]	r	rule reference.

Exceptions

Any	exception propagated by the rule, the lattice or the PRNG construction.

Definition at line 406 of file tpl_ca_update_scheme.H.

References Aleph::CA::apply_rule(), Aleph::blossom_maximum_cardinality_matching(), Aleph::CA::ca_scheme_detail::cell_count(), Aleph::CA::gather_neighbors(), Aleph::CA::Random_Asynchronous_Update< Engine_Type >::master_seed, Aleph::CA::mix_seed(), Aleph::next(), r, and Aleph::CA::Random_Asynchronous_Update< Engine_Type >::sub_steps_per_step.

Member Data Documentation

master_seed

template<typename Engine_Type = std::mt19937_64>

std::uint64_t Aleph::CA::Random_Asynchronous_Update< Engine_Type >::master_seed = 0

Definition at line 379 of file tpl_ca_update_scheme.H.

Referenced by Aleph::CA::Random_Asynchronous_Update< Engine_Type >::apply().

requires_block_rule

template<typename Engine_Type = std::mt19937_64>

constexpr bool Aleph::CA::Random_Asynchronous_Update< Engine_Type >::requires_block_rule = false

staticconstexpr

Operates on cell rules.

Definition at line 377 of file tpl_ca_update_scheme.H.

requires_double_buffer

template<typename Engine_Type = std::mt19937_64>

constexpr bool Aleph::CA::Random_Asynchronous_Update< Engine_Type >::requires_double_buffer = false

staticconstexpr

In-place updates → no second buffer.

Definition at line 375 of file tpl_ca_update_scheme.H.

sub_steps_per_step

template<typename Engine_Type = std::mt19937_64>

std::size_t Aleph::CA::Random_Asynchronous_Update< Engine_Type >::sub_steps_per_step = 0

Number of single-cell sub-steps per step().

0 means "as many sub-steps as there are cells in the lattice".

Definition at line 382 of file tpl_ca_update_scheme.H.

Referenced by Aleph::CA::Random_Asynchronous_Update< Engine_Type >::apply().

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The documentation for this struct was generated from the following file:

• tpl_ca_update_scheme.H