uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage > Class Template Reference

Directional MPO environment cache borrowed from finite MPS and MPO owners. More...

#include <environment_cache.hpp>

Public Types
using	auxiliary_space_type = typename mpo_type::auxiliary_space_type
using	bond_space_type = typename mps_type::bond_space_type
using	environment_type = MpoEnvironment< value_type, bond_space_type, auxiliary_space_type, bond_space_type, EnvironmentStorage >
using	mpo_block_type = block_tensor_const_block_t< typename mpo_type::site_type >
using	mpo_type = std::remove_cvref_t< MpoChain >
using	mps_type = std::remove_cvref_t< MpsChain >
using	value_type = typename mps_type::value_type

Public Member Functions
void	build_all ()
	Build every left and right environment entry.
auto	is_attached_to (mps_type const &mps, mpo_type const &mpo) const noexcept -> bool
	Return whether this cache observes the supplied chain objects.
auto	left_cached (std::size_t bond) -> bool
	Return whether the left environment at a bond is currently cached.
auto	left_environment (std::size_t bond) -> environment_type const &
	Build and return the left environment at one bond.
	MpoEnvironmentCache (mps_type const &mps, mpo_type const &mpo, std::size_t left_auxiliary_index, std::size_t right_auxiliary_index)
	Construct boundary entries and validate the coupled chains.
auto	right_cached (std::size_t bond) -> bool
	Return whether the right environment at a bond is currently cached.
auto	right_environment (std::size_t bond) -> environment_type const &
	Build and return the right environment at one bond.
auto	size () const noexcept -> std::size_t
	Return the number of physical sites.

Detailed Description

template<class MpsChain, class MpoChain, SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>
class uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >

Directional MPO environment cache borrowed from finite MPS and MPO owners.

The cache stores one left and one right environment at every bond. Entries are built lazily or with build_all(). Site revisions automatically invalidate the exact directional suffix or prefix that depends on a replacement.

Warning

The referenced owners must outlive the cache, remain at their original addresses, and be mutated only through their replacement members while the cache exists.

Template Parameters

MpsChain	Concrete FiniteMps type.
MpoChain	Concrete FiniteMpo type.
EnvironmentStorage	Sparse local storage for cached values.

Member Typedef Documentation

auxiliary_space_type

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

using uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::auxiliary_space_type = typename mpo_type::auxiliary_space_type

bond_space_type

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

using uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::bond_space_type = typename mps_type::bond_space_type

environment_type

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

using uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::environment_type = MpoEnvironment<value_type, bond_space_type, auxiliary_space_type, bond_space_type, EnvironmentStorage>

mpo_block_type

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

using uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::mpo_block_type = block_tensor_const_block_t<typename mpo_type::site_type>

mpo_type

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

using uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::mpo_type = std::remove_cvref_t<MpoChain>

mps_type

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

using uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::mps_type = std::remove_cvref_t<MpsChain>

value_type

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

using uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::value_type = typename mps_type::value_type

Constructor & Destructor Documentation

MpoEnvironmentCache()

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::MpoEnvironmentCache ( mps_type const &  mps, mpo_type const &  mpo, std::size_t  left_auxiliary_index, std::size_t  right_auxiliary_index  )

inline

Construct boundary entries and validate the coupled chains.

Parameters

mps	Borrowed finite MPS owner.
mpo	Borrowed finite MPO owner of the same length.
left_auxiliary_index	Identity-charge state at the left MPO boundary.
right_auxiliary_index	Identity-charge state at the right MPO boundary.

Exceptions

std::invalid_argument

If chain sizes, symmetries, or physical spaces differ, or either boundary state is invalid.

Member Function Documentation

build_all()

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

void uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::build_all ( )

inline

Build every left and right environment entry.

is_attached_to()

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

auto uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::is_attached_to ( mps_type const &  mps, mpo_type const &  mpo  ) const -> bool

inlinenoexcept

Return whether this cache observes the supplied chain objects.

This identity check lets compound algorithms reject a cache constructed for different owners of the same concrete types.

Parameters

mps	Candidate finite MPS owner.
mpo	Candidate finite MPO owner.

left_cached()

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

auto uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::left_cached ( std::size_t  bond ) -> bool

inline

Return whether the left environment at a bond is currently cached.

Parameters

bond	Bond index in [0, size()].

Exceptions

std::out_of_range

If bond is invalid.

left_environment()

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

auto uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::left_environment ( std::size_t  bond ) -> environment_type const&

inline

Build and return the left environment at one bond.

Bond zero is the left identity boundary. Bond i+1 extends bond i across site i.

Warning

The returned reference is invalidated when a later cache observation detects a replacement on which this entry depends.

Parameters

bond	Bond index in [0, size()].

Exceptions

std::out_of_range

If bond is invalid.

right_cached()

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

auto uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::right_cached ( std::size_t  bond ) -> bool

inline

Return whether the right environment at a bond is currently cached.

Parameters

bond	Bond index in [0, size()].

Exceptions

std::out_of_range

If bond is invalid.

right_environment()

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

auto uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::right_environment ( std::size_t  bond ) -> environment_type const&

inline

Build and return the right environment at one bond.

Bond size() is the right identity boundary. Bond i extends bond i+1 across site i from right to left.

Warning

The returned reference is invalidated when a later cache observation detects a replacement on which this entry depends.

Parameters

bond	Bond index in [0, size()].

Exceptions

std::out_of_range

If bond is invalid.

size()

template<class MpsChain , class MpoChain , SparseBlockStorage EnvironmentStorage = SeparateSparseBlockStorage<>>

auto uni20::tensor_network::MpoEnvironmentCache< MpsChain, MpoChain, EnvironmentStorage >::size ( ) const -> std::size_t

inlinenoexcept

Return the number of physical sites.

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

• environment_cache.hpp