cdf< C > Struct Template Reference

CDF data structure. More...

#include <cdf.h>

Public Types
using	value_type = bbm::iterable_value_t< C >
using	index_type = index_t< value_type >

Public Member Functions
constexpr	cdf (void)
	Trivial constructor.
constexpr	cdf (const C &samples)
	Constructor.
constexpr	cdf (const cdf &src)
	Copy Constructor.
constexpr cdf	operator= (const cdf &src)
	Assigmemnt.
size_t	size (void) const
	number of samples
auto	sample (const value_type &xi, index_mask_t< index_type > mask=true) const
	sample the CDF given a random variable xi
auto	pdf (const index_type &idx, index_mask_t< index_type > mask=true) const
	querry the PDF that an index will be sampled.

Private Attributes
std::decay_t< C >	_cdf
	Data.

Detailed Description

template<typename C>
requires std::ranges::range<C>
struct bbm::cdf< C >

CDF data structure.

Template Parameters

C	= container type to store CDF as well as to provide samples for construction.

Requires that the container 'C' is a range.

Member Typedef Documentation

index_type

using index_type = index_t<value_type>

value_type

using value_type = bbm::iterable_value_t<C>

Constructor & Destructor Documentation

cdf() [1/3]

constexpr cdf ( void  )

inlineconstexpr

Trivial constructor.

cdf() [2/3]

constexpr cdf ( const C &  samples )

inlineconstexpr

Constructor.

Parameters

samples

a iterable container of samples (in order).

The samples will be integrated into a CDF and normalized.

cdf() [3/3]

constexpr cdf ( const cdf< C > &  src )

inlineconstexpr

Copy Constructor.

Member Function Documentation

operator=()

constexpr cdf operator= ( const cdf< C > &  src )

inlineconstexpr

Assigmemnt.

pdf()

auto pdf ( const index_type &  idx, index_mask_t< index_type >  mask = true  ) const

inline

querry the PDF that an index will be sampled.

Parameters

idx	= index to sample (must be in [0, size()-1]
mask	= enable/disable lanes

Returns

the pdf, which is equivalent to the normalized sample value.

sample()

auto sample ( const value_type &  xi, index_mask_t< index_type >  mask = true  ) const

inline

sample the CDF given a random variable xi

Parameters

xi	= random variable between 0 and 1
mask	= enable/disable lanes.

Returns

sampled index, the pdf, and the residual

The value type and index type are determined by the container itself. The random variable is expected to be provided in the same data type as the value type of the container. Hence, if the container stores a packet type, the we also expect the random variable be given as a packet, and the index type to have the same number of channels.

The returned type is a tuple of:

• the sampled index based on xi
• the corresponding pdf of the sample
• the residual, i.e., the rescaled entropy of xi that was not used to determine the sample.

size()

size_t size ( void  ) const

inline

number of samples

Member Data Documentation

_cdf

std::decay_t<C> _cdf

private

Data.

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

• include/util/cdf.h