mpqc::HBSparseTensor< RR, RC, Abs, T > Class Template Reference

Documentation

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>
class mpqc::HBSparseTensor< RR, RC, Abs, T >

Heat-bath sparse representation of a tensor of rank RI+RO

Note

HB representation is akin to CSR of tensor matricized RI x RO, with rows sorted by magnitude

Template Parameters

RR	row rank
RC	column rank
Abs	if true, will store the absolute values of the elements only
T	the element type

Classes
struct	Element
struct	Value

Public Types
using	row_index_type = std::array< orbital_index_type, RR >
using	col_index_type = std::array< orbital_index_type, RC >
using	real_type = float
using	magnitude_type = real_type
using	empty_type = struct {}
using	element_data_type = Element
using	row_type = std::vector< element_data_type >
using	row_iterator_type = typename row_type::iterator

Public Member Functions
template<typename Tensor >
	HBSparseTensor (const Tensor &dense_tensor, magnitude_type epsilon)
const auto &	row (const row_index_type &idx) const
bool	row_exists (const row_index_type &idx) const
const auto &	maxabs_element () const

Friends
template<class CharT , class Traits , std::size_t RR_, std::size_t RC_, bool Abs_, typename T_ >
std::basic_ostream< CharT, Traits > &	operator<< (std::basic_ostream< CharT, Traits > &, const HBSparseTensor< RR_, RC_, Abs_, T_ > &)

Member Typedef Documentation

col_index_type

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

using mpqc::HBSparseTensor< RR, RC, Abs, T >::col_index_type = std::array<orbital_index_type, RC>

element_data_type

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

using mpqc::HBSparseTensor< RR, RC, Abs, T >::element_data_type = Element

empty_type

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

using mpqc::HBSparseTensor< RR, RC, Abs, T >::empty_type = struct {}

magnitude_type

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

using mpqc::HBSparseTensor< RR, RC, Abs, T >::magnitude_type = real_type

real_type

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

using mpqc::HBSparseTensor< RR, RC, Abs, T >::real_type = float

row_index_type

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

using mpqc::HBSparseTensor< RR, RC, Abs, T >::row_index_type = std::array<orbital_index_type, RR>

row_iterator_type

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

using mpqc::HBSparseTensor< RR, RC, Abs, T >::row_iterator_type = typename row_type::iterator

row_type

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

using mpqc::HBSparseTensor< RR, RC, Abs, T >::row_type = std::vector<element_data_type>

Constructor & Destructor Documentation

HBSparseTensor()

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

template<typename Tensor >

mpqc::HBSparseTensor< RR, RC, Abs, T >::HBSparseTensor ( const Tensor &  dense_tensor, magnitude_type  epsilon  )

inline

Template Parameters

Tensor

a dense tensor type

Parameters

[in]	dense_tensor	a dense tensor, with first RC modes serving as the row modes
[in]	epsilon	all values in dense_tensor of magnitude smaller than this are ignored

Member Function Documentation

maxabs_element()

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

const auto& mpqc::HBSparseTensor< RR, RC, Abs, T >::maxabs_element ( ) const

inline

Returns

{{row_idx,col_idx},abs_value} of the element with the largest magnitude; if all elements were screened out abs_value will be -1.

row()

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

const auto& mpqc::HBSparseTensor< RR, RC, Abs, T >::row ( const row_index_type &  idx ) const

inline

Parameters

[in]

idx

row index

Returns

(reference to) the row element {col_idx,value} pairs, sorted in the order of descending magnitude

Precondition

this->row_exists(idx) == true

row_exists()

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

bool mpqc::HBSparseTensor< RR, RC, Abs, T >::row_exists ( const row_index_type &  idx ) const

inline

Parameters

[in]

idx

row index

Returns

true if row idx has at least 1 nonzero value

Friends And Related Function Documentation

operator<<

template<std::size_t RR, std::size_t RC, bool Abs = false, typename T = double>

template<class CharT , class Traits , std::size_t RR_, std::size_t RC_, bool Abs_, typename T_ >

std::basic_ostream<CharT, Traits>& operator<< ( std::basic_ostream< CharT, Traits > &  , const HBSparseTensor< RR_, RC_, Abs_, T_ > &    )

friend

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

• mpqc/math/fock/hb.h