JSUPPORT::JRandomSampler< T > Struct Template Reference

Template class for randomly sampling from a JLANG::JRewindableObjectIterator using a JLANG::JObjectSampler. More...

#include <JRandomSampler.hh>

Public Member Functions
	JRandomSampler ()
	Default constructor. More...
	JRandomSampler (const unsigned int on, const unsigned int off)
	Constructor. More...
const JRandomSampler &	getRandomSampler () const
	Get random sampler. More...
JRandomSampler &	getRandomSampler ()
	Get random sampler. More...
skip_type	operator() (const T &object) const
	Acceptance test operator. More...

Protected Attributes
skip_type	averageOn
skip_type	averageOff
skip_type	count

Friends
std::istream &	operator>> (std::istream &in, JRandomSampler &sampler)
	Read random sampler from input. More...
std::ostream &	operator<< (std::ostream &out, const JRandomSampler &sampler)
	Write random sampler to output. More...

Detailed Description

template<class T>
struct JSUPPORT::JRandomSampler< T >

Template class for randomly sampling from a JLANG::JRewindableObjectIterator using a JLANG::JObjectSampler.

The JRandomSampler class provides for an implementation of randomly sampling objects.
The sampling is controlled via two parameters, namely:

• a sequential iteration of a predefined average number of objects (JRandomSampler::averageOn); and
• a predefined average number of objects to skip (JRandomSampler::averageOff).

Definition at line 31 of file JRandomSampler.hh.

Constructor & Destructor Documentation

template<class T>

JSUPPORT::JRandomSampler< T >::JRandomSampler ( )

inline

Default constructor.

This constructor will sample all objects.

Definition at line 37 of file JRandomSampler.hh.

                     :
      averageOn (1),
      averageOff(0),
      count     (0)
    {}

template<class T>

JSUPPORT::JRandomSampler< T >::JRandomSampler ( const unsigned int  on, const unsigned int  off  )

inline

Constructor.

Parameters

on	average number of consecutively accepted events
off	average number of consecutively rejected events

Definition at line 50 of file JRandomSampler.hh.

                                           :
      averageOn (on),
      averageOff(off),
      count     (0)
    {}

Member Function Documentation

template<class T>

const JRandomSampler& JSUPPORT::JRandomSampler< T >::getRandomSampler ( ) const

inline

Get random sampler.

Returns

random sampler

Definition at line 63 of file JRandomSampler.hh.

    {
      return static_cast<const JRandomSampler&>(*this);
    }

template<class T>

JRandomSampler& JSUPPORT::JRandomSampler< T >::getRandomSampler ( )

inline

Get random sampler.

Returns

random sampler

Definition at line 74 of file JRandomSampler.hh.

    {
      return static_cast<JRandomSampler&>(*this);
    }

template<class T>

skip_type JSUPPORT::JRandomSampler< T >::operator() ( const T &  object ) const

inline

Acceptance test operator.

Return value 0 means accept and >0 number of objects to skip.

Parameters

object

object

Returns

number of objects to skip

Definition at line 87 of file JRandomSampler.hh.

    {
      if (count == 0) {

        count  = gRandom->Integer(2 * averageOn);

        return (skip_type) gRandom->Integer(2 * averageOff);

      } else {

        count -= 1;

        return 0;
      }
    }

Friends And Related Function Documentation

template<class T>

std::istream& operator>> ( std::istream &  in, JRandomSampler< T > &  sampler  )

friend

Read random sampler from input.

Parameters

in	input stream
sampler	random sampler

Returns

input stream

Definition at line 111 of file JRandomSampler.hh.

    {
      in >> sampler.averageOn;
      in >> sampler.averageOff;
      
      sampler.count = 0;

      return in;
    }

template<class T>

std::ostream& operator<< ( std::ostream &  out, const JRandomSampler< T > &  sampler  )

friend

Write random sampler to output.

Parameters

out	output stream
sampler	random sampler

Returns

output stream

Definition at line 129 of file JRandomSampler.hh.

    {
      out << sampler.averageOn;
      out << ' ';
      out << sampler.averageOff;

      return out;
    }

Member Data Documentation

template<class T>

skip_type JSUPPORT::JRandomSampler< T >::averageOn

protected

Definition at line 139 of file JRandomSampler.hh.

template<class T>

skip_type JSUPPORT::JRandomSampler< T >::averageOff

protected

Definition at line 140 of file JRandomSampler.hh.

template<class T>

skip_type JSUPPORT::JRandomSampler< T >::count

mutableprotected

Definition at line 141 of file JRandomSampler.hh.

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

• JRandomSampler.hh