C++ types and functions for calculating the log-likelihood for POVM effects which can be written as a product of individual effects. More...

#include <tomographer/densedm/indepmeasllh.h>

Public Types
enum
	Declare some stuff as part of the DenseLLH Interface compliance. More...

typedef DMTypes_	DMTypes
	The DMTypes in use here.

typedef LLHValueType_	LLHValueType
	Type used to calculate the log-likelihood function (see DenseLLH Interface)

typedef IntFreqType_	IntFreqType
	Type used to store integer measurement counts.

typedef Eigen::Matrix< typename DMTypes::RealScalar, Eigen::Dynamic, DMTypes::FixedDim2, Eigen::RowMajor, FixedMaxParamList, DMTypes::FixedDim2 >	VectorParamListType
	dynamic Matrix with rows = dim*dim Vectors (row-major) [maximum FixedMaxParamList rows, or Dynamic]

typedef const Eigen::Ref< const VectorParamListType > &	VectorParamListTypeConstRef
	Const ref to a VectorParamListType.

typedef VectorParamListType::Index	IndexType
	Type used to index entries in VectorParamListType (and also used for indexing entries in FreqListType)

typedef Eigen::Array< IntFreqType, Eigen::Dynamic, 1, 0, FixedMaxParamList, 1 >	FreqListType
	dynamic Array of integers [maximum FixedMaxParamList entries or Dynamic]

typedef const Eigen::Ref< const FreqListType > &	FreqListTypeConstRef
	Const ref to a FreqListType.

Public Member Functions
	IndepMeasLLH (DMTypes dmt_)
	Simple constructor. More...

	IndepMeasLLH (DMTypes dmt_, VectorParamListTypeConstRef Exn_, FreqListTypeConstRef Nx_)
	Constructor with full measurement data. More...

const IndexType	numEffects () const
	The number of POVM effects in the list. More...

const VectorParamListType &	Exn () const
	The stored individual POVM effects, in X Parameterization. More...

Eigen::Ref< const typename DMTypes::VectorParamType >	Exn (IndexType i) const
	The i-th stored POVM effect, in X Parameterization. More...

const FreqListType &	Nx () const
	The stored frequency counts for each individual POVM effect. More...

const IntFreqType	Nx (IndexType i) const
	The number of counts stored for the i-th POVM effect. More...

void	resetMeas ()
	Reset the measurement vectors and frequency counts. More...

void	addMeasEffect (typename DMTypes::VectorParamTypeConstRef E_x, IntFreqType n, bool check_validity=true)
	Store a measurement POVM effect along with a frequency count. More...

void	addMeasEffect (typename DMTypes::MatrixTypeConstRef E_m, IntFreqType n, bool check_validity=true)
	Store a POVM measurement effect with frequency count. More...

void	setMeas (VectorParamListTypeConstRef Exn_, FreqListTypeConstRef Nx_, bool check_validity=true)
	Specify the full measurement data at once. More...

void	checkAllMeas () const

void	checkEffect (IndexType i) const

template<ENABLED_IF( UseNMeasAmplifyFactor) >
LLHValueType	NMeasAmplifyFactor () const
	Factor by which to artificially amplify the number of measurements. More...

template<ENABLED_IF( !UseNMeasAmplifyFactor) >
LLHValueType	NMeasAmplifyFactor () const
	Basic implementation of NMeasAmplifyFactor() if this feature is disabled.

template<ENABLED_IF( UseNMeasAmplifyFactor) >
void	setNMeasAmplifyFactor (LLHValueType val)
	Set the factor by which to artificially multiply all frequency counts. More...

LLHValueType	logLikelihoodX (typename DMTypes::VectorParamTypeConstRef x) const
	Calculates the log-likelihood function, in X parameterization. More...

Public Attributes
const DMTypes	dmt
	The DMTypes object, storing e.g. the dimension of the problem.

Static Public Attributes
static constexpr int	FixedMaxParamList = FixedMaxParamList_
	Maximum number of POVM effects, fixed at compile-time or Eigen::Dynamic.

static constexpr bool	IsDynamicMaxParamList = (FixedMaxParamList_ == Eigen::Dynamic)
	Whether the dimension is specified dynamically at run-time or statically at compile-time.

static constexpr bool	UseNMeasAmplifyFactor = UseNMeasAmplifyFactor_
	Whether we allow NMeasAmplifyFactor to be set.

Detailed Description

template<typename DMTypes_, typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>
class Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >

C++ types and functions for calculating the log-likelihood for POVM effects which can be written as a product of individual effects.

Implements the DenseLLH Interface.

Since: Since Tomographer 5.3, a pointer to this class can be serialized with Boost.Serialization.

Definition at line 69 of file indepmeasllh.h.

Member Enumeration Documentation

§ anonymous enum

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

anonymous enum

Declare some stuff as part of the DenseLLH Interface compliance.

See DenseDM::LLHCalcTypeX and DenseLLH Interface for details.

Enumerator
LLHCalcType	Declare that this DenseLLH object exposes a logLikelihoodX() method.

Definition at line 90 of file indepmeasllh.h.

Constructor & Destructor Documentation

§ IndepMeasLLH() [1/2]

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::IndepMeasLLH ( DMTypes dmt_ )

inline

Simple constructor.

The measurement data is initialially empty. You may call addMeasEffect() or setMeas() to specify the measurement data.

Definition at line 121 of file indepmeasllh.h.

§ IndepMeasLLH() [2/2]

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::IndepMeasLLH	(	DMTypes	dmt_,
		VectorParamListTypeConstRef	Exn_,
		FreqListTypeConstRef	Nx_
	)

inline

Constructor with full measurement data.

The measurement data is set to Exn_ and Nx_ via a call to setMeas().

Definition at line 131 of file indepmeasllh.h.

Member Function Documentation

§ addMeasEffect() [1/2]

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

void Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::addMeasEffect	(	typename DMTypes::VectorParamTypeConstRef	E_x,
		IntFreqType	n,
		bool	check_validity = `true`
	)

inline

Store a measurement POVM effect along with a frequency count.

Parameters

E_x	the X-parameterization of the POVM effect corresponding to the observed measurement outcome
n	the number of times this POVM effect was observed in the experiment
check_validity	Perform some sanity checks, verifying the E_x and n are valid inputs

If n is zero, then the measurement effect is ignored and not stored. This is because the outcome was never observed in the experiment; furthermore we can't have zero entries in the Nx() vector because that would cause "0*log(0)" terms in our logLikelihoodX() calculation and create a mess of NaNs And Infs.

Definition at line 220 of file indepmeasllh.h.

§ addMeasEffect() [2/2]

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

void Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::addMeasEffect	(	typename DMTypes::MatrixTypeConstRef	E_m,
		IntFreqType	n,
		bool	check_validity = `true`
	)

inline

Store a POVM measurement effect with frequency count.

This overload accepts the POVM effect specified as a dense matrix instead of a X Parameterization.

See addMeasEffect(typename DMTypes::VectorParamTypeConstRef E_x, IntFreqType n, bool check_validity = true).

Definition at line 256 of file indepmeasllh.h.

§ Exn() [1/2]

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

const VectorParamListType& Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::Exn ( ) const

inline

The stored individual POVM effects, in X Parameterization.

This is an Eigen::Array type (2-D), whose rows are the x-parameterization representation of the POVM effects.

The number of rows of Exn must be equal to the number of rows of Nx. Use setMeas() or addMeasEffect() to populate measurements.

§ Exn() [2/2]

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

Eigen::Ref<const typename DMTypes::VectorParamType> Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::Exn ( IndexType i ) const

inline

The i-th stored POVM effect, in X Parameterization.

Returns the i-th stored POVM effect, in X-parameterization, as a column vector.

§ logLikelihoodX()

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

LLHValueType Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::logLikelihoodX ( typename DMTypes::VectorParamTypeConstRef x ) const

inline

Calculates the log-likelihood function, in X parameterization.

Returns: the value of the log-likelihood function of this data at the point x, defined as
\[ \log\Lambda(\texttt{x}) = \sum_k \texttt{Nx[k]}\,\ln\mathrm{tr}(\texttt{Exn[k]}\,\rho(\texttt{x})) . \]

Note: this does not include a sometimes conventional factor \( -2\).

Definition at line 384 of file indepmeasllh.h.

§ NMeasAmplifyFactor()

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

template<ENABLED_IF( UseNMeasAmplifyFactor) >

LLHValueType Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::NMeasAmplifyFactor ( ) const

inline

Factor by which to artificially amplify the number of measurements.

This should always be set to one for any physical experiment. It is only useful for tests.

Definition at line 359 of file indepmeasllh.h.

§ numEffects()

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

const IndexType Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::numEffects ( ) const

inline

The number of POVM effects in the list.

Returns the size of the list of POVM effects. They are not guaranteed to be different (although this is usually the case); that depends on what the user specified to setMeas().

Definition at line 146 of file indepmeasllh.h.

§ Nx() [1/2]

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

const FreqListType& Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::Nx ( ) const

inline

The stored frequency counts for each individual POVM effect.

This is an Eigen::Array object (1-D), of an integer type, which stores the number of times the corresponding POVM effect (given in the corresponding row in Exn) was observed in the experiment.

The number of rows of Exn must be equal to the number of rows of Nx. Use setMeas() or addMeasEffect to specify the measurement data.

§ Nx() [2/2]

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

const IntFreqType Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::Nx ( IndexType i ) const

inline

The number of counts stored for the i-th POVM effect.

Returns the frequency count corresponding to the i-th POVM effect, i.e. the number of times this POVM effect was observed in the experiment.

§ resetMeas()

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

void Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::resetMeas ( )

inline

Reset the measurement vectors and frequency counts.

Resets the measurement data to an empty list. Consequently the return values of Exn() and Nx() are subsequently empty vectors.

Definition at line 199 of file indepmeasllh.h.

§ setMeas()

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

void Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::setMeas	(	VectorParamListTypeConstRef	Exn_,
		FreqListTypeConstRef	Nx_,
		bool	check_validity = `true`
	)

inline

Specify the full measurement data at once.

Definition at line 279 of file indepmeasllh.h.

§ setNMeasAmplifyFactor()

template<typename DMTypes_ , typename LLHValueType_ = typename DMTypes_::RealScalar, typename IntFreqType_ = int, int FixedMaxParamList_ = Eigen::Dynamic, bool UseNMeasAmplifyFactor_ = false>

template<ENABLED_IF( UseNMeasAmplifyFactor) >

void Tomographer::DenseDM::IndepMeasLLH< DMTypes_, LLHValueType_, IntFreqType_, FixedMaxParamList_, UseNMeasAmplifyFactor_ >::setNMeasAmplifyFactor ( LLHValueType val )

inline

Set the factor by which to artificially multiply all frequency counts.

Only use this for tests and debugging. It does not have any meaning for actual measurement data, as with this you are altering the numbers that you observed in the experiment!

Definition at line 372 of file indepmeasllh.h.

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

tomographer/densedm/indepmeasllh.h (v5.3)

Public Types

Public Member Functions

Public Attributes

Static Public Attributes

Detailed Description

Member Enumeration Documentation

§ anonymous enum

Constructor & Destructor Documentation

§ IndepMeasLLH() [1/2]

§ IndepMeasLLH() [2/2]

Member Function Documentation

§ addMeasEffect() [1/2]

§ addMeasEffect() [2/2]

§ Exn() [1/2]

§ Exn() [2/2]

§ logLikelihoodX()

§ NMeasAmplifyFactor()

§ numEffects()

§ Nx() [1/2]

§ Nx() [2/2]

§ resetMeas()

§ setMeas()

§ setNMeasAmplifyFactor()