Represents a vector with entries of type T. More...

#include <dai/prob.h>

Public Types
typedef std::vector< T >	container_type
	Type of data structure used for storing the values. More...

typedef TProb< T >	this_type
	Shorthand. More...

typedef container_type::const_iterator	const_iterator
	Constant iterator over the elements. More...

typedef container_type::iterator	iterator
	Iterator over the elements. More...

typedef container_type::const_reverse_iterator	const_reverse_iterator
	Constant reverse iterator over the elements. More...

typedef container_type::reverse_iterator	reverse_iterator
	Reverse iterator over the elements. More...

Public Member Functions
template<typename binOp1 , typename binOp2 >
T	innerProduct (const this_type &q, T init, binOp1 binaryOp1, binOp2 binaryOp2) const
	Performs a generalized inner product, similar to std::inner_product. More...

Constructors and destructors
	TProb ()
	Default constructor (constructs empty vector) More...

	TProb (size_t n)
	Construct uniform probability distribution over n outcomes (i.e., a vector of length n with each entry set to ) More...

	TProb (size_t n, T p)
	Construct vector of length n with each entry set to p. More...

template<typename TIterator >
	TProb (TIterator begin, TIterator end, size_t sizeHint)
	Construct vector from a range. More...

template<typename S >
	TProb (const std::vector< S > &v)
	Construct vector from another vector. More...

Iterator interface
iterator	begin ()
	Returns iterator that points to the first element. More...

const_iterator	begin () const
	Returns constant iterator that points to the first element. More...

iterator	end ()
	Returns iterator that points beyond the last element. More...

const_iterator	end () const
	Returns constant iterator that points beyond the last element. More...

reverse_iterator	rbegin ()
	Returns reverse iterator that points to the last element. More...

const_reverse_iterator	rbegin () const
	Returns constant reverse iterator that points to the last element. More...

reverse_iterator	rend ()
	Returns reverse iterator that points beyond the first element. More...

const_reverse_iterator	rend () const
	Returns constant reverse iterator that points beyond the first element. More...

Miscellaneous operations
void	resize (size_t sz)

Get/set individual entries
T	get (size_t i) const
	Gets i 'th entry. More...

void	set (size_t i, T val)
	Sets i 'th entry to val. More...

Queries
const container_type &	p () const
	Returns a const reference to the wrapped container. More...

container_type &	p ()
	Returns a reference to the wrapped container. More...

T	operator[] (size_t i) const
	Returns a copy of the i 'th entry. More...

size_t	size () const
	Returns length of the vector (i.e., the number of entries) More...

template<typename unOp >
T	accumulateSum (T init, unOp op) const
	Accumulate all values (similar to std::accumulate) by summing. More...

template<typename unOp >
T	accumulateMax (T init, unOp op, bool minimize) const
	Accumulate all values (similar to std::accumulate) by maximization/minimization. More...

T	entropy () const
	Returns the Shannon entropy of `*this`, $-\sum_i p_i \log p_i$ . More...

T	max () const
	Returns maximum value of all entries. More...

T	min () const
	Returns minimum value of all entries. More...

T	sum () const
	Returns sum of all entries. More...

T	sumAbs () const
	Return sum of absolute value of all entries. More...

T	maxAbs () const
	Returns maximum absolute value of all entries. More...

bool	hasNaNs () const
	Returns `true` if one or more entries are NaN. More...

bool	hasNegatives () const
	Returns `true` if one or more entries are negative. More...

std::pair< size_t, T >	argmax () const
	Returns a pair consisting of the index of the maximum value and the maximum value itself. More...

size_t	draw ()
	Returns a random index, according to the (normalized) distribution described by *this. More...

bool	operator< (const this_type &q) const
	Lexicographical comparison. More...

bool	operator== (const this_type &q) const
	Comparison. More...

std::string	toString () const
	Formats a TProb as a string. More...

Unary transformations
template<typename unaryOp >
this_type	pwUnaryTr (unaryOp op) const
	Returns the result of applying operation op pointwise on `*this`. More...

this_type	operator- () const
	Returns negative of `*this`. More...

this_type	abs () const
	Returns pointwise absolute value. More...

this_type	exp () const
	Returns pointwise exponent. More...

this_type	log (bool zero=false) const
	Returns pointwise logarithm. More...

this_type	inverse (bool zero=true) const
	Returns pointwise inverse. More...

this_type	normalized (ProbNormType norm=dai::NORMPROB) const
	Returns normalized copy of `*this`, using the specified norm. More...

Unary operations
template<typename unaryOp >
this_type &	pwUnaryOp (unaryOp op)
	Applies unary operation op pointwise. More...

this_type &	randomize ()
	Draws all entries i.i.d. from a uniform distribution on [0,1) More...

this_type &	setUniform ()
	Sets all entries to where n is the length of the vector. More...

this_type &	takeAbs ()
	Applies absolute value pointwise. More...

this_type &	takeExp ()
	Applies exponent pointwise. More...

this_type &	takeLog (bool zero=false)
	Applies logarithm pointwise. More...

T	normalize (ProbNormType norm=dai::NORMPROB)
	Normalizes vector using the specified norm. More...

Operations with scalars
this_type &	fill (T x)
	Sets all entries to x. More...

this_type &	operator+= (T x)
	Adds scalar x to each entry. More...

this_type &	operator-= (T x)
	Subtracts scalar x from each entry. More...

this_type &	operator*= (T x)
	Multiplies each entry with scalar x. More...

this_type &	operator/= (T x)
	Divides each entry by scalar x, where division by 0 yields 0. More...

this_type &	operator^= (T x)
	Raises entries to the power x. More...

Transformations with scalars
this_type	operator+ (T x) const
	Returns sum of `*this` and scalar x. More...

this_type	operator- (T x) const
	Returns difference of `*this` and scalar x. More...

this_type	operator* (T x) const
	Returns product of `*this` with scalar x. More...

this_type	operator/ (T x) const
	Returns quotient of `*this` and scalar x, where division by 0 yields 0. More...

this_type	operator^ (T x) const
	Returns `*this` raised to the power x. More...

Operations with other equally-sized vectors
template<typename binaryOp >
this_type &	pwBinaryOp (const this_type &q, binaryOp op)
	Applies binary operation pointwise on two vectors. More...

this_type &	operator+= (const this_type &q)
	Pointwise addition with q. More...

this_type &	operator-= (const this_type &q)
	Pointwise subtraction of q. More...

this_type &	operator*= (const this_type &q)
	Pointwise multiplication with q. More...

this_type &	operator/= (const this_type &q)
	Pointwise division by q, where division by 0 yields 0. More...

this_type &	divide (const this_type &q)
	Pointwise division by q, where division by 0 yields +Inf. More...

this_type &	operator^= (const this_type &q)
	Pointwise power. More...

Transformations with other equally-sized vectors
template<typename binaryOp >
this_type	pwBinaryTr (const this_type &q, binaryOp op) const
	Returns the result of applying binary operation op pointwise on `*this` and q. More...

this_type	operator+ (const this_type &q) const
	Returns sum of `*this` and q. More...

this_type	operator- (const this_type &q) const
	Return `*this` minus q. More...

this_type	operator* (const this_type &q) const
	Return product of `*this` with q. More...

this_type	operator/ (const this_type &q) const
	Returns quotient of `*this` with q, where division by 0 yields 0. More...

this_type	divided_by (const this_type &q) const
	Pointwise division by q, where division by 0 yields +Inf. More...

this_type	operator^ (const this_type &q) const
	Returns `*this` to the power q. More...

Private Attributes
container_type	_p
	The data structure that stores the values. More...

Related Functions
(Note that these are not member functions.)
template<typename T >
T	dist (const TProb< T > &p, const TProb< T > &q, ProbDistType dt)
	Returns distance between p and q, measured using distance measure dt. More...

template<typename T >
std::ostream &	operator<< (std::ostream &os, const TProb< T > &p)
	Writes a TProb<T> to an output stream. More...

template<typename T >
TProb< T >	min (const TProb< T > &a, const TProb< T > &b)
	Returns the pointwise minimum of a and b. More...

template<typename T >
TProb< T >	max (const TProb< T > &a, const TProb< T > &b)
	Returns the pointwise maximum of a and b. More...

Detailed Description

template<typename T>
class dai::TProb< T >

Represents a vector with entries of type T.

It is simply a std::vector<T> with an interface designed for dealing with probability mass functions.

It is mainly used for representing measures on a finite outcome space, for example, the probability distribution of a discrete random variable. However, entries are not necessarily non-negative; it is also used to represent logarithms of probability mass functions.

Template Parameters

T	Should be a scalar that is castable from and to dai::Real and should support elementary arithmetic operations.

Member Typedef Documentation

template<typename T>

typedef std::vector<T> dai::TProb< T >::container_type

Type of data structure used for storing the values.

template<typename T>

typedef TProb<T> dai::TProb< T >::this_type

Shorthand.

template<typename T>

typedef container_type::const_iterator dai::TProb< T >::const_iterator

Constant iterator over the elements.

template<typename T>

typedef container_type::iterator dai::TProb< T >::iterator

Iterator over the elements.

template<typename T>

typedef container_type::const_reverse_iterator dai::TProb< T >::const_reverse_iterator

Constant reverse iterator over the elements.

template<typename T>

typedef container_type::reverse_iterator dai::TProb< T >::reverse_iterator

Reverse iterator over the elements.

Constructor & Destructor Documentation

template<typename T>

dai::TProb< T >::TProb ( )

inline

Default constructor (constructs empty vector)

template<typename T>

dai::TProb< T >::TProb ( size_t n )

inlineexplicit

Construct uniform probability distribution over n outcomes (i.e., a vector of length n with each entry set to $1/n$ )

template<typename T>

dai::TProb< T >::TProb	(	size_t	n,
		T	p
	)

inlineexplicit

Construct vector of length n with each entry set to p.

template<typename T>

template<typename TIterator >

dai::TProb< T >::TProb	(	TIterator	begin,
		TIterator	end,
		size_t	sizeHint
	)

inline

Construct vector from a range.

Template Parameters

TIterator Iterates over instances that can be cast to T

Parameters

begin	Points to first instance to be added.
end	Points just beyond last instance to be added.
sizeHint	For efficiency, the number of entries can be speficied by sizeHint; the value 0 can be given if the size is unknown, but this will result in a performance penalty.

template<typename T>

template<typename S >

dai::TProb< T >::TProb ( const std::vector< S > & v )

inline

Construct vector from another vector.

Template Parameters

S	type of elements in v (should be castable to type T)

Parameters

v	vector used for initialization.

Member Function Documentation

template<typename T>

iterator dai::TProb< T >::begin ( )

inline

Returns iterator that points to the first element.

template<typename T>

const_iterator dai::TProb< T >::begin ( ) const

inline

Returns constant iterator that points to the first element.

template<typename T>

iterator dai::TProb< T >::end ( )

inline

Returns iterator that points beyond the last element.

template<typename T>

const_iterator dai::TProb< T >::end ( ) const

inline

Returns constant iterator that points beyond the last element.

template<typename T>

reverse_iterator dai::TProb< T >::rbegin ( )

inline

Returns reverse iterator that points to the last element.

template<typename T>

const_reverse_iterator dai::TProb< T >::rbegin ( ) const

inline

Returns constant reverse iterator that points to the last element.

template<typename T>

reverse_iterator dai::TProb< T >::rend ( )

inline

Returns reverse iterator that points beyond the first element.

template<typename T>

const_reverse_iterator dai::TProb< T >::rend ( ) const

inline

Returns constant reverse iterator that points beyond the first element.

template<typename T>

T dai::TProb< T >::get ( size_t i ) const

inline

Gets i 'th entry.

template<typename T>

void dai::TProb< T >::set	(	size_t	i,
		T	val
	)

inline

Sets i 'th entry to val.

template<typename T>

const container_type& dai::TProb< T >::p ( ) const

inline

Returns a const reference to the wrapped container.

template<typename T>

container_type& dai::TProb< T >::p ( )

inline

Returns a reference to the wrapped container.

template<typename T>

T dai::TProb< T >::operator[] ( size_t i ) const

inline

Returns a copy of the i 'th entry.

template<typename T>

size_t dai::TProb< T >::size ( ) const

inline

Returns length of the vector (i.e., the number of entries)

template<typename T>

template<typename unOp >

T dai::TProb< T >::accumulateSum	(	T	init,
		unOp	op
	)		const

inline

Accumulate all values (similar to std::accumulate) by summing.

The following calculation is done:

T t = op(init);
for( const_iterator it = begin(); it != end(); it++ )
    t += op(*it);
return t;

template<typename T>

template<typename unOp >

T dai::TProb< T >::accumulateMax	(	T	init,
		unOp	op,
		bool	minimize
	)		const

inline

Accumulate all values (similar to std::accumulate) by maximization/minimization.

The following calculation is done (with "max" replaced by "min" if minimize == true):

T t = op(init);
for( const_iterator it = begin(); it != end(); it++ )
    t = std::max( t, op(*it) );
return t;

template<typename T>

T dai::TProb< T >::entropy ( ) const

inline

Returns the Shannon entropy of *this, $-\sum_i p_i \log p_i$ .

template<typename T>

T dai::TProb< T >::max ( ) const

inline

Returns maximum value of all entries.

template<typename T>

T dai::TProb< T >::min ( ) const

inline

Returns minimum value of all entries.

template<typename T>

T dai::TProb< T >::sum ( ) const

inline

Returns sum of all entries.

template<typename T>

T dai::TProb< T >::sumAbs ( ) const

inline

Return sum of absolute value of all entries.

template<typename T>

T dai::TProb< T >::maxAbs ( ) const

inline

Returns maximum absolute value of all entries.

template<typename T>

bool dai::TProb< T >::hasNaNs ( ) const

inline

Returns true if one or more entries are NaN.

template<typename T>

bool dai::TProb< T >::hasNegatives ( ) const

inline

Returns true if one or more entries are negative.

template<typename T>

std::pair<size_t,T> dai::TProb< T >::argmax ( ) const

inline

Returns a pair consisting of the index of the maximum value and the maximum value itself.

template<typename T>

size_t dai::TProb< T >::draw ( )

inline

Returns a random index, according to the (normalized) distribution described by *this.

template<typename T>

bool dai::TProb< T >::operator< ( const this_type & q ) const

inline

Lexicographical comparison.

Precondition: this->size() == q.size()

template<typename T>

bool dai::TProb< T >::operator== ( const this_type & q ) const

inline

Comparison.

template<typename T>

std::string dai::TProb< T >::toString ( ) const

inline

Formats a TProb as a string.

template<typename T>

template<typename unaryOp >

this_type dai::TProb< T >::pwUnaryTr ( unaryOp op ) const

inline

Returns the result of applying operation op pointwise on *this.

template<typename T>

this_type dai::TProb< T >::operator- ( ) const

inline

Returns negative of *this.

template<typename T>

this_type dai::TProb< T >::abs ( ) const

inline

Returns pointwise absolute value.

template<typename T>

this_type dai::TProb< T >::exp ( ) const

inline

Returns pointwise exponent.

template<typename T>

this_type dai::TProb< T >::log ( bool zero = false ) const

inline

Returns pointwise logarithm.

If zero == true, uses log(0)==0; otherwise, log(0)==-Inf.

template<typename T>

this_type dai::TProb< T >::inverse ( bool zero = true ) const

inline

Returns pointwise inverse.

If zero == true, uses 1/0==0; otherwise, 1/0==Inf.

template<typename T>

this_type dai::TProb< T >::normalized ( ProbNormType norm = dai::NORMPROB ) const

inline

Returns normalized copy of *this, using the specified norm.

Exceptions

NOT_NORMALIZABLE if the norm is zero

template<typename T>

template<typename unaryOp >

this_type& dai::TProb< T >::pwUnaryOp ( unaryOp op )

inline

Applies unary operation op pointwise.

template<typename T>

this_type& dai::TProb< T >::randomize ( )

inline

Draws all entries i.i.d. from a uniform distribution on [0,1)

template<typename T>

this_type& dai::TProb< T >::setUniform ( )

inline

Sets all entries to $1/n$ where n is the length of the vector.

template<typename T>

this_type& dai::TProb< T >::takeAbs ( )

inline

Applies absolute value pointwise.

template<typename T>

this_type& dai::TProb< T >::takeExp ( )

inline

Applies exponent pointwise.

template<typename T>

this_type& dai::TProb< T >::takeLog ( bool zero = false )

inline

Applies logarithm pointwise.

If zero == true, uses log(0)==0; otherwise, log(0)==-Inf.

template<typename T>

T dai::TProb< T >::normalize ( ProbNormType norm = dai::NORMPROB )

inline

Normalizes vector using the specified norm.

Exceptions

NOT_NORMALIZABLE if the norm is zero

template<typename T>

this_type& dai::TProb< T >::fill ( T x )

inline

Sets all entries to x.

template<typename T>

this_type& dai::TProb< T >::operator+= ( T x )

inline

Adds scalar x to each entry.

template<typename T>

this_type& dai::TProb< T >::operator-= ( T x )

inline

Subtracts scalar x from each entry.

template<typename T>

this_type& dai::TProb< T >::operator*= ( T x )

inline

Multiplies each entry with scalar x.

template<typename T>

this_type& dai::TProb< T >::operator/= ( T x )

inline

Divides each entry by scalar x, where division by 0 yields 0.

template<typename T>

this_type& dai::TProb< T >::operator^= ( T x )

inline

Raises entries to the power x.

template<typename T>

this_type dai::TProb< T >::operator+ ( T x ) const

inline

Returns sum of *this and scalar x.

template<typename T>

this_type dai::TProb< T >::operator- ( T x ) const

inline

Returns difference of *this and scalar x.

template<typename T>

this_type dai::TProb< T >::operator* ( T x ) const

inline

Returns product of *this with scalar x.

template<typename T>

this_type dai::TProb< T >::operator/ ( T x ) const

inline

Returns quotient of *this and scalar x, where division by 0 yields 0.

template<typename T>

this_type dai::TProb< T >::operator^ ( T x ) const

inline

Returns *this raised to the power x.

template<typename T>

template<typename binaryOp >

this_type& dai::TProb< T >::pwBinaryOp	(	const this_type &	q,
		binaryOp	op
	)

inline

Applies binary operation pointwise on two vectors.

Template Parameters

binaryOp Type of function object that accepts two arguments of type T and outputs a type T

Parameters

q	Right operand
op	Operation of type binaryOp

template<typename T>

this_type& dai::TProb< T >::operator+= ( const this_type & q )

inline

Pointwise addition with q.

Precondition: this->size() == q.size()

template<typename T>

this_type& dai::TProb< T >::operator-= ( const this_type & q )

inline

Pointwise subtraction of q.

Precondition: this->size() == q.size()

template<typename T>

this_type& dai::TProb< T >::operator*= ( const this_type & q )

inline

Pointwise multiplication with q.

Precondition: this->size() == q.size()

template<typename T>

this_type& dai::TProb< T >::operator/= ( const this_type & q )

inline

Pointwise division by q, where division by 0 yields 0.

Precondition: this->size() == q.size()

See also: divide(const TProb<T> &)

template<typename T>

this_type& dai::TProb< T >::divide ( const this_type & q )

inline

Pointwise division by q, where division by 0 yields +Inf.

Precondition: this->size() == q.size()

See also: operator/=(const TProb<T> &)

template<typename T>

this_type& dai::TProb< T >::operator^= ( const this_type & q )

inline

Pointwise power.

Precondition: this->size() == q.size()

template<typename T>

template<typename binaryOp >

this_type dai::TProb< T >::pwBinaryTr	(	const this_type &	q,
		binaryOp	op
	)		const

inline

Returns the result of applying binary operation op pointwise on *this and q.

Template Parameters

binaryOp Type of function object that accepts two arguments of type T and outputs a type T

Parameters

q	Right operand
op	Operation of type binaryOp

template<typename T>

this_type dai::TProb< T >::operator+ ( const this_type & q ) const

inline

Returns sum of *this and q.

Precondition: this->size() == q.size()

template<typename T>

this_type dai::TProb< T >::operator- ( const this_type & q ) const

inline

Return *this minus q.

Precondition: this->size() == q.size()

template<typename T>

this_type dai::TProb< T >::operator* ( const this_type & q ) const

inline

Return product of *this with q.

Precondition: this->size() == q.size()

template<typename T>

this_type dai::TProb< T >::operator/ ( const this_type & q ) const

inline

Returns quotient of *this with q, where division by 0 yields 0.

Precondition: this->size() == q.size()

See also: divided_by(const TProb<T> &)

template<typename T>

this_type dai::TProb< T >::divided_by ( const this_type & q ) const

inline

Pointwise division by q, where division by 0 yields +Inf.

Precondition: this->size() == q.size()

See also: operator/(const TProb<T> &)

template<typename T>

this_type dai::TProb< T >::operator^ ( const this_type & q ) const

inline

Returns *this to the power q.

Precondition: this->size() == q.size()

template<typename T>

template<typename binOp1 , typename binOp2 >

T dai::TProb< T >::innerProduct	(	const this_type &	q,
		T	init,
		binOp1	binaryOp1,
		binOp2	binaryOp2
	)		const

inline

Performs a generalized inner product, similar to std::inner_product.

Precondition: this->size() == q.size()

Friends And Related Function Documentation

template<typename T >

T dist	(	const TProb< T > &	p,
		const TProb< T > &	q,
		ProbDistType	dt
	)

Precondition: this->size() == q.size()

template<typename T >

std::ostream & operator<<	(	std::ostream &	os,
		const TProb< T > &	p
	)

template<typename T >

TProb< T > min	(	const TProb< T > &	a,
		const TProb< T > &	b
	)

Precondition: this->size() == q.size()

template<typename T >

TProb< T > max	(	const TProb< T > &	a,
		const TProb< T > &	b
	)

Precondition: this->size() == q.size()

Member Data Documentation

template<typename T>

container_type dai::TProb< T >::_p

private

The data structure that stores the values.

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

include/dai/prob.h

Public Types

Public Member Functions

Private Attributes

Related Functions

Detailed Description

template<typename T> class dai::TProb< T >

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation

template<typename T>
class dai::TProb< T >