TabulatedRngEngine Class Reference

Engine for TabulatedRandomGenerator. More...

#include <TabulatedRandomGenerator.h>

Collaboration diagram for TabulatedRngEngine:

[legend]

List of all members.

Public Member Functions
	TabulatedRngEngine (Dataset &dataset)
	Constructor from a dataset.
constexpr value_t	MaxValue () const
	Returns maximal possible value of stored random numbers.
value_t	Read (int channel) const
	Reads the random number for the given channel for the current event.
int	Register (int numChannels=1)
	Registers a new consumer of random numbers.
Private Attributes
int	numChannelsRegistered_
	Total number of channels registered.
int const	kSeed_ = 1439
	The seed to fill the table of random numbers.
int const	kVolume_ = 100'000
	Number of random numbers to generate.
std::vector< value_t >	table_
	Table of pre-generated random numbers.
TTreeReaderValue< ULong64_t >	event_
	Reader to access the event number from event ID.

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Detailed Description

Engine for TabulatedRandomGenerator.

This class provides fixed random numbers. Multiple numbers per event can be obtained using different channels. The number returned for a given channel in an event with a given ID, is always the same.

This class is not expected to be used directly but via TabulatedRandomGenerator instead. Each instance of the latter registers itself as a consumer of random numbers.

Internally, a table of pre-generated random integer numbers is maintained. Its elements are indexed by the current event number and given channel number. The table is treated as a circular buffer.

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Member Function Documentation

value_t TabulatedRngEngine::Read

(

int

channel

)

const

Reads the random number for the given channel for the current event.

It is responsibility of the caller to include the offset returned by Register into the provided channel number. No check on the given channel number is done.

int TabulatedRngEngine::Register

(

int

numChannels = 1

)

Registers a new consumer of random numbers.

The consumer must respect the returned offset to ensure that the set of random numbers it reads does not overlap with the sets read by other consumers.

Parameters:

[in]

numChannels

Number of random numbers that can be used by this consumer per event.

Returns:

Offset that determines the start of the range of channels allocated for this consumer.

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

• include/TabulatedRandomGenerator.h
• src/TabulatedRandomGenerator.cc