ParitySector< ManyBodySpace, RealType > Class Template Reference

Parity invariant sector of a many-body Hilbert space. More...

#include <ParitySector.hpp>

Inheritance diagram for ParitySector< ManyBodySpace, RealType >:

Collaboration diagram for ParitySector< ManyBodySpace, RealType >:

Public Types
using	Base = SubSpace< ManyBodySpace, RealType >
Public Types inherited from SubSpace< TotalSpace_, ScalarType_ >
using	TotalSpace = TotalSpace_
using	Scalar = ScalarType_
using	Real = typename Eigen::NumTraits< ScalarType_ >::Real

Public Member Functions
template<typename std::enable_if_t< std::is_convertible_v< ManyBodySpace, ManyBodySpaceBase< ManyBodySpace > > > * = nullptr>
__host__ __device__	ParitySector (int parity, ManyBodySpace const &mbHSpace)
	Construct a ParitySector object from a ManyBodySpace object.
template<typename... Args>
__host__ __device__	ParitySector (int parity, int systemSize, Args... args)
	Default constructor.
__host__ __device__ int	parity () const
__host__ __device__ int	rep (int j, int trans=0) const
__host__ __device__ int	period (int j) const
Public Member Functions inherited from SubSpace< TotalSpace_, ScalarType_ >
__host__ __device__	SubSpace (TotalSpace const &totalSpace)
	Construct a SubSpace object by copying totalSpace to its member variable (m_totalSpace)
__host__ __device__	SubSpace (TotalSpace &&totalSpace)
	Construct a SubSpace object by moving totalSpace to its member variable (m_totalSpace)
__host__ __device__	SubSpace ()=default
	Default constructor.
__host__ __device__	SubSpace (SubSpace const &other)=default
	Copy constructor.
template<typename Scalar_ >
__host__ __device__	SubSpace (SubSpace< TotalSpace_, Scalar_ > const &other)
__host__ __device__	SubSpace (SubSpace &&other)=default
	Move constructor.
__host__ __device__	~SubSpace ()=default
	Destructor.
__host__ __device__ SubSpace &	operator= (SubSpace const &other)
	Copy assignment operator.
__host__ __device__ SubSpace &	operator= (SubSpace &&other)
	Move assignment operator.
__host__ __device__ bool	operator== (SubSpace const &other) const
	Equality operator.
__host__ __device__ Matrix_t &	basis ()
__host__ __device__ Matrix_t const &	basis () const
__host__ __device__ TotalSpace const &	totalSpace () const
__host__ __device__ int	dimTot () const
Public Member Functions inherited from HilbertSpace< Derived >
__host__ __device__ int	dim () const
__host__ __device__ bool	operator== (HilbertSpace const &other) const

Private Member Functions
__host__ __device__ int	numParityPairs ()

Private Attributes
int	m_parity
int	m_NumParityEigens = 0

Additional Inherited Members
Protected Types inherited from SubSpace< TotalSpace_, ScalarType_ >
using	Matrix_t = SparseCompressed< Scalar >
using	Matrix_t = Eigen::SparseMatrix< Scalar >
Protected Attributes inherited from SubSpace< TotalSpace_, ScalarType_ >
TotalSpace	m_totalSpace
Matrix_t	m_basisStates

Detailed Description

template<class ManyBodySpace, typename RealType = Real_t>
class ParitySector< ManyBodySpace, RealType >

Parity invariant sector of a many-body Hilbert space.

Template Parameters

Scalar_t
int
Matrix

Member Typedef Documentation

Base

template<class ManyBodySpace , typename RealType = Real_t>

using ParitySector< ManyBodySpace, RealType >::Base = SubSpace<ManyBodySpace, RealType>

Constructor & Destructor Documentation

ParitySector() [1/2]

template<class ManyBodySpace , typename RealType = Real_t>

template<typename std::enable_if_t< std::is_convertible_v< ManyBodySpace, ManyBodySpaceBase< ManyBodySpace > > > * = nullptr>

__host__ __device__ ParitySector< ManyBodySpace, RealType >::ParitySector ( int  parity, ManyBodySpace const &  mbHSpace  )

inline

Construct a ParitySector object from a ManyBodySpace object.

Parameters

k
mbHSpace

            : Base(mbHSpace), m_parity(parity) {
            debug_constructor_printf(1);
            assert(parity == +1 || parity == -1);
            if(this->totalSpace().sysSize() == 0) { return; }
 
            Eigen::ArrayX<bool> calculated = Eigen::ArrayX<bool>::Constant(mbHSpace.dim(), false);
            for(int state = 0; state != mbHSpace.dim(); ++state) {
                if(calculated[state]) continue;
                calculated[state] = true;
 
                int reversed = mbHSpace.reverse(state);
                if(reversed == state)
                    m_NumParityEigens += 1;
                else
                    calculated[reversed] = true;
            }
            int dim = (mbHSpace.dim() - m_NumParityEigens) / 2;
            if(m_parity == +1) dim += m_NumParityEigens;
            debug_print("mbHSpace.dim() = " << mbHSpace.dim() << ", dim = " << dim
                                            << ", m_NumParityEigens = " << m_NumParityEigens);
 
            this->basis().resize(mbHSpace.dim(), dim);
            this->basis().reserve(Eigen::VectorXi::Constant(dim, 2));
            dim        = 0;
            calculated = Eigen::ArrayX<bool>::Constant(mbHSpace.dim(), false);
            Eigen::ArrayXi parityEigen(m_NumParityEigens);
            m_NumParityEigens = 0;
            for(int state = 0; state != mbHSpace.dim(); ++state) {
                if(calculated[state]) continue;
                calculated[state] = true;
 
                int reversed = mbHSpace.reverse(state);
                if(reversed == state) { parityEigen(m_NumParityEigens++) = state; }
                else {
                    this->basis().insert(state, dim)    = 1.0 / sqrt(2.0);
                    this->basis().insert(reversed, dim) = 1.0 / sqrt(2.0);
                    calculated[reversed]                = true;
                    dim += 1;
                }
            }
            if(m_parity == 1) {
                for(int j = 0; j != parityEigen.size(); ++j)
                    this->basis().insert(parityEigen[j], dim++) = 1;
            }
 
            debug_print("mbHSpace.dim() = " << mbHSpace.dim() << ", dim = " << dim
                                            << ", this->dim() = " << this->dim());
            this->basis().makeCompressed();
            assert(dim == this->dim());
        };

ParitySector() [2/2]

template<class ManyBodySpace , typename RealType = Real_t>

template<typename... Args>

__host__ __device__ ParitySector< ManyBodySpace, RealType >::ParitySector ( int  parity, int  systemSize, Args...  args  )

inline

Default constructor.

Parameters

k
systemSize
dimLoc

            : ParitySector(parity, ManyBodySpace(systemSize, args...)) {
            debug_constructor_printf((Default));
        }

Member Function Documentation

numParityPairs()

template<class ManyBodySpace , typename RealType = Real_t>

__host__ __device__ int ParitySector< ManyBodySpace, RealType >::numParityPairs ( )

inlineprivate

                                                 {
            assert((this->dim() - m_NumParityEigens) % 2 == 0);
            return (this->dim() - m_NumParityEigens) / 2;
        }

parity()

template<class ManyBodySpace , typename RealType = Real_t>

__host__ __device__ int ParitySector< ManyBodySpace, RealType >::parity ( ) const

inline

{ return m_parity; };

period()

template<class ManyBodySpace , typename RealType = Real_t>

__host__ __device__ int ParitySector< ManyBodySpace, RealType >::period ( int  j ) const

inline

                                                    {
            assert(j < this->dim() && "j < this->dim()");
            return this->basis().outerIndexPtr()[j + 1] - this->basis().outerIndexPtr()[j];
        };

rep()

template<class ManyBodySpace , typename RealType = Real_t>

__host__ __device__ int ParitySector< ManyBodySpace, RealType >::rep ( int  j, int  trans = 0  ) const

inline

                                                                {
            assert(j < this->dim());
            int const period
                = this->basis().outerIndexPtr()[j + 1] - this->basis().outerIndexPtr()[j];
            int const innerId = this->basis().outerIndexPtr()[j] + (trans % period);
            assert(innerId < this->basis().nonZeros());
            return this->basis().innerIndexPtr()[innerId];
        };

Member Data Documentation

m_NumParityEigens

template<class ManyBodySpace , typename RealType = Real_t>

int ParitySector< ManyBodySpace, RealType >::m_NumParityEigens = 0

private

m_parity

template<class ManyBodySpace , typename RealType = Real_t>

int ParitySector< ManyBodySpace, RealType >::m_parity

private

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

• /Users/shoki/GitHub/Locality/Headers/HilbertSpace/ParitySector.hpp