The Random Number Generator (RNG) that has a specified empirical distribution. More...

#include <random-variable-stream.h>

Inheritance diagram for ns3::EmpiricalRandomVariable:

Classes
class	ValueCDF

Public Member Functions
	EmpiricalRandomVariable ()
	Creates an empirical RNG that has a specified, empirical distribution.

void	CDF (double v, double c)
	Specifies a point in the empirical distribution. More...

virtual uint32_t	GetInteger (void)
	Returns the next value in the empirical distribution. More...

virtual double	GetValue (void)
	Returns the next value in the empirical distribution. More...

Public Member Functions inherited from ns3::RandomVariableStream
int64_t	GetStream (void) const
	Returns the stream number for this RNG stream. More...

bool	IsAntithetic (void) const
	Returns true if antithetic values should be generated. More...

void	SetAntithetic (bool isAntithetic)
	Specifies whether antithetic values should be generated. More...

void	SetStream (int64_t stream)
	Specifies the stream number for this RNG stream. More...

Public Member Functions inherited from ns3::Object
void	AggregateObject (Ptr< Object > other)

void	Dispose (void)

AggregateIterator	GetAggregateIterator (void) const

virtual TypeId	GetInstanceTypeId (void) const

template<typename T >
Ptr< T >	GetObject (void) const

template<typename T >
Ptr< T >	GetObject (TypeId tid) const

void	Initialize (void)

Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
	SimpleRefCount (const SimpleRefCount &o)

uint32_t	GetReferenceCount (void) const

SimpleRefCount &	operator= (const SimpleRefCount &o)

void	Ref (void) const

void	Unref (void) const

Public Member Functions inherited from ns3::ObjectBase
void	GetAttribute (std::string name, AttributeValue &value) const

bool	GetAttributeFailSafe (std::string name, AttributeValue &attribute) const

void	SetAttribute (std::string name, const AttributeValue &value)

bool	SetAttributeFailSafe (std::string name, const AttributeValue &value)

bool	TraceConnect (std::string name, std::string context, const CallbackBase &cb)

bool	TraceConnectWithoutContext (std::string name, const CallbackBase &cb)

bool	TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)

bool	TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)

Static Public Member Functions
static TypeId	GetTypeId (void)

Static Public Member Functions inherited from ns3::RandomVariableStream
static TypeId	GetTypeId (void)

Static Public Member Functions inherited from ns3::Object
static TypeId	GetTypeId (void)

Static Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
static void	Cleanup (void)

Static Public Member Functions inherited from ns3::ObjectBase
static TypeId	GetTypeId (void)

Private Member Functions
virtual double	Interpolate (double, double, double, double, double)

virtual void	Validate ()

Private Attributes
std::vector< ValueCDF >	emp

bool	validated

Additional Inherited Members
Protected Member Functions inherited from ns3::RandomVariableStream
RngStream *	Peek (void) const
	Returns a pointer to the underlying RNG stream.

Protected Member Functions inherited from ns3::Object
	Object (const Object &o)

virtual void	DoDispose (void)

virtual void	DoInitialize (void)

virtual void	NotifyNewAggregate (void)

Protected Member Functions inherited from ns3::ObjectBase
void	ConstructSelf (const AttributeConstructionList &attributes)

virtual void	NotifyConstructionCompleted (void)

Detailed Description

The Random Number Generator (RNG) that has a specified empirical distribution.

Defines a random variable that has a specified, empirical distribution. The distribution is specified by a series of calls to the CDF member function, specifying a value and the probability that the function value is less than the specified value. When values are requested, a uniform random variable is used to select a probability, and the return value is interpreted linearly between the two appropriate points in the CDF. The method is known as inverse transform sampling: (http://en.wikipedia.org/wiki/Inverse_transform_sampling).

Here is an example of how to use this class:

// Create the RNG with a uniform distribution between 0 and 10.
Ptr<EmpiricalRandomVariable> x = CreateObject<EmpiricalRandomVariable> ();
x->CDF ( 0.0,  0.0);
x->CDF ( 5.0,  0.5);
x->CDF (10.0,  1.0);
// The expected value for the mean of the values returned by this
// empirical distribution is the midpoint of the distribution
//
//     E[value]  =  5 .
//                          
double value = x->GetValue ();

Config Paths

ns3::EmpiricalRandomVariable is accessible through the following paths with Config::Set and Config::Connect:

/ChannelList/[i]/$ns3::WifiChannel/$ns3::YansWifiChannel/PropagationDelayModel/$ns3::RandomPropagationDelayModel/Variable/$ns3::EmpiricalRandomVariable
/ChannelList/[i]/$ns3::WifiChannel/$ns3::YansWifiChannel/PropagationLossModel/$ns3::RandomPropagationLossModel/Variable/$ns3::EmpiricalRandomVariable
/ChannelList/[i]/$ns3::YansWifiChannel/PropagationDelayModel/$ns3::RandomPropagationDelayModel/Variable/$ns3::EmpiricalRandomVariable
/ChannelList/[i]/$ns3::YansWifiChannel/PropagationLossModel/$ns3::RandomPropagationLossModel/Variable/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::GaussMarkovMobilityModel/MeanDirection/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::GaussMarkovMobilityModel/MeanPitch/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::GaussMarkovMobilityModel/MeanVelocity/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomDirection2dMobilityModel/Pause/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomDirection2dMobilityModel/Speed/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWalk2dMobilityModel/Direction/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWalk2dMobilityModel/Speed/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/Pause/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/PositionAllocator/$ns3::RandomBoxPositionAllocator/X/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/PositionAllocator/$ns3::RandomBoxPositionAllocator/Y/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/PositionAllocator/$ns3::RandomBoxPositionAllocator/Z/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/PositionAllocator/$ns3::RandomDiscPositionAllocator/Rho/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/PositionAllocator/$ns3::RandomDiscPositionAllocator/Theta/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/PositionAllocator/$ns3::RandomRectanglePositionAllocator/X/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/PositionAllocator/$ns3::RandomRectanglePositionAllocator/Y/$ns3::EmpiricalRandomVariable
/NodeList/[i]/$ns3::MobilityModel/$ns3::RandomWaypointMobilityModel/Speed/$ns3::EmpiricalRandomVariable
/NodeList/[i]/ApplicationList/[i]/$ns3::OnOffApplication/OffTime/$ns3::EmpiricalRandomVariable
/NodeList/[i]/ApplicationList/[i]/$ns3::OnOffApplication/OnTime/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::CsmaNetDevice/ReceiveErrorModel/$ns3::BurstErrorModel/BurstSize/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::CsmaNetDevice/ReceiveErrorModel/$ns3::BurstErrorModel/BurstStart/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::CsmaNetDevice/ReceiveErrorModel/$ns3::RateErrorModel/RanVar/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::PointToPointNetDevice/ReceiveErrorModel/$ns3::BurstErrorModel/BurstSize/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::PointToPointNetDevice/ReceiveErrorModel/$ns3::BurstErrorModel/BurstStart/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::PointToPointNetDevice/ReceiveErrorModel/$ns3::RateErrorModel/RanVar/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::SimpleNetDevice/ReceiveErrorModel/$ns3::BurstErrorModel/BurstSize/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::SimpleNetDevice/ReceiveErrorModel/$ns3::BurstErrorModel/BurstStart/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::SimpleNetDevice/ReceiveErrorModel/$ns3::RateErrorModel/RanVar/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Channel/$ns3::YansWifiChannel/PropagationDelayModel/$ns3::RandomPropagationDelayModel/Variable/$ns3::EmpiricalRandomVariable
/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Channel/$ns3::YansWifiChannel/PropagationLossModel/$ns3::RandomPropagationLossModel/Variable/$ns3::EmpiricalRandomVariable

No Attributes are defined for this type.
No TraceSources are defined for this type.

Definition at line 2373 of file random-variable-stream.h.

Member Function Documentation

void ns3::EmpiricalRandomVariable::CDF	(	double	v,
		double	c
	)

Specifies a point in the empirical distribution.

Parameters

v	The function value for this point
c	Probability that the function is less than or equal to v

Definition at line 1589 of file random-variable-stream.cc.

References NS_LOG_FUNCTION.

Referenced by RandomVariableStreamEmpiricalTestCase::DoRun(), and RandomVariableStreamEmpiricalAntitheticTestCase::DoRun().

uint32_t ns3::EmpiricalRandomVariable::GetInteger ( void )

virtual

Returns the next value in the empirical distribution.

Returns: The integer next value in the empirical distribution.

Note that antithetic values are being generated if m_isAntithetic is equal to true. If $u$ is a uniform variable over [0,1] and $x$ is a value that would be returned normally, then $(1 - u$ ) is the distance that $u$ would be from $1$ . The value returned in the antithetic case, $x'$ , uses (1-u), which is the distance $u$ is from the 1.

Implements ns3::RandomVariableStream.

Definition at line 1583 of file random-variable-stream.cc.

References GetValue(), and NS_LOG_FUNCTION.

double ns3::EmpiricalRandomVariable::GetValue ( void )

virtual

Returns the next value in the empirical distribution.

Returns: The floating point next value in the empirical distribution.

Note that antithetic values are being generated if m_isAntithetic is equal to true. If $u$ is a uniform variable over [0,1] and $x$ is a value that would be returned normally, then $(1 - u$ ) is the distance that $u$ would be from $1$ . The value returned in the antithetic case, $x'$ , uses (1-u), which is the distance $u$ is from the 1.

Implements ns3::RandomVariableStream.

Definition at line 1529 of file random-variable-stream.cc.

References ns3::RandomVariableStream::IsAntithetic(), NS_LOG_FUNCTION, ns3::RandomVariableStream::Peek(), and ns3::RngStream::RandU01().

Referenced by RandomVariableStreamEmpiricalTestCase::DoRun(), RandomVariableStreamEmpiricalAntitheticTestCase::DoRun(), and GetInteger().

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

src/core/model/random-variable-stream.h
src/core/model/random-variable-stream.cc

Classes

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Config Paths

Member Function Documentation