The binomial distribution Random Number Generator (RNG). More...
#include "random-variable-stream.h"
Public Member Functions | |
BinomialRandomVariable () | |
virtual uint32_t | GetInteger () |
Get the next random value drawn from the distribution. | |
uint32_t | GetInteger (uint32_t trials, uint32_t probability) |
Get the next random value drawn from the distribution. | |
double | GetValue () override |
Get the next random value drawn from the distribution. | |
double | GetValue (uint32_t trials, double probability) |
Get the next random value drawn from the distribution. | |
Public Member Functions inherited from ns3::RandomVariableStream | |
RandomVariableStream () | |
Default constructor. | |
RandomVariableStream (const RandomVariableStream &)=delete | |
~RandomVariableStream () override | |
Destructor. | |
int64_t | GetStream () const |
Returns the stream number for the RngStream. | |
bool | IsAntithetic () const |
Check if antithetic values will be generated. | |
RandomVariableStream & | operator= (const RandomVariableStream &)=delete |
void | SetAntithetic (bool isAntithetic) |
Specify whether antithetic values should be generated. | |
void | SetStream (int64_t stream) |
Specifies the stream number for the RngStream. | |
Public Member Functions inherited from ns3::Object | |
Object () | |
Constructor. | |
~Object () override | |
Destructor. | |
void | AggregateObject (Ptr< Object > other) |
Aggregate two Objects together. | |
void | Dispose () |
Dispose of this Object. | |
AggregateIterator | GetAggregateIterator () const |
Get an iterator to the Objects aggregated to this one. | |
TypeId | GetInstanceTypeId () const override |
Get the most derived TypeId for this Object. | |
template<typename T > | |
Ptr< T > | GetObject () const |
Get a pointer to the requested aggregated Object. | |
template<> | |
Ptr< Object > | GetObject () const |
Specialization of () for objects of type ns3::Object. | |
template<typename T > | |
Ptr< T > | GetObject (TypeId tid) const |
Get a pointer to the requested aggregated Object by TypeId. | |
template<> | |
Ptr< Object > | GetObject (TypeId tid) const |
Specialization of (TypeId tid) for objects of type ns3::Object. | |
void | Initialize () |
Invoke DoInitialize on all Objects aggregated to this one. | |
bool | IsInitialized () const |
Check if the object has been initialized. | |
void | UnidirectionalAggregateObject (Ptr< Object > other) |
Aggregate an Object to another Object. | |
Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter > | |
SimpleRefCount () | |
Default constructor. | |
SimpleRefCount (const SimpleRefCount &o) | |
Copy constructor. | |
uint32_t | GetReferenceCount () const |
Get the reference count of the object. | |
SimpleRefCount & | operator= (const SimpleRefCount &o) |
Assignment operator. | |
void | Ref () const |
Increment the reference count. | |
void | Unref () const |
Decrement the reference count. | |
Public Member Functions inherited from ns3::ObjectBase | |
virtual | ~ObjectBase () |
Virtual destructor. | |
void | GetAttribute (std::string name, AttributeValue &value, bool permissive=false) const |
Get the value of an attribute, raising fatal errors if unsuccessful. | |
bool | GetAttributeFailSafe (std::string name, AttributeValue &value) const |
Get the value of an attribute without raising errors. | |
void | SetAttribute (std::string name, const AttributeValue &value) |
Set a single attribute, raising fatal errors if unsuccessful. | |
bool | SetAttributeFailSafe (std::string name, const AttributeValue &value) |
Set a single attribute without raising errors. | |
bool | TraceConnect (std::string name, std::string context, const CallbackBase &cb) |
Connect a TraceSource to a Callback with a context. | |
bool | TraceConnectWithoutContext (std::string name, const CallbackBase &cb) |
Connect a TraceSource to a Callback without a context. | |
bool | TraceDisconnect (std::string name, std::string context, const CallbackBase &cb) |
Disconnect from a TraceSource a Callback previously connected with a context. | |
bool | TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb) |
Disconnect from a TraceSource a Callback previously connected without a context. | |
Static Public Member Functions | |
static TypeId | GetTypeId () |
Register this type. | |
Static Public Member Functions inherited from ns3::RandomVariableStream | |
static TypeId | GetTypeId () |
Register this type. | |
Static Public Member Functions inherited from ns3::Object | |
static TypeId | GetTypeId () |
Register this type. | |
Static Public Member Functions inherited from ns3::ObjectBase | |
static TypeId | GetTypeId () |
Get the type ID. | |
Private Attributes | |
double | m_probability |
The probability of success in each trial. | |
uint32_t | m_trials |
The number of trials. | |
Additional Inherited Members | |
Protected Member Functions inherited from ns3::RandomVariableStream | |
RngStream * | Peek () const |
Get the pointer to the underlying RngStream. | |
Protected Member Functions inherited from ns3::Object | |
Object (const Object &o) | |
Copy an Object. | |
virtual void | DoDispose () |
Destructor implementation. | |
virtual void | DoInitialize () |
Initialize() implementation. | |
virtual void | NotifyNewAggregate () |
Notify all Objects aggregated to this one of a new Object being aggregated. | |
Protected Member Functions inherited from ns3::ObjectBase | |
void | ConstructSelf (const AttributeConstructionList &attributes) |
Complete construction of ObjectBase; invoked by derived classes. | |
virtual void | NotifyConstructionCompleted () |
Notifier called once the ObjectBase is fully constructed. | |
Related Symbols inherited from ns3::ObjectBase | |
static TypeId | GetObjectIid () |
Ensure the TypeId for ObjectBase gets fully configured to anchor the inheritance tree properly. | |
The binomial distribution Random Number Generator (RNG).
This class supports the creation of objects that return random numbers from a fixed binomial distribution. It also supports the generation of single random numbers from various binomial distributions.
The probability mass function of a binomial variable is defined as:
where is the number of trials and is the probability of success in each trial. The mean of this distribution is and the variance is .
The Binomial RNG value for a given number of trials and success probability is generated by
where is a uniform random variable on [0,1) for each trial, and is an indicator function that is 1 if and 0 otherwise. The sum of these indicator functions over all trials gives the total number of successes, which is the value of the binomial random variable.
Here is an example of how to use this class:
If an instance of this RNG is configured to return antithetic values, the actual value returned, , for the Binomial process is determined by:
where is a uniform random variable on [0,1) for each trial. The antithetic approach uses instead of in the indicator function.
There are alternative methods for generating binomial distributions that may offer greater efficiency. However, this implementation opts for a simpler approach. Although not as efficient, this method was chosen for its simplicity and sufficiency in most applications.
ns3::BinomialRandomVariable is accessible through the following paths with Config::Set and Config::Connect:
No TraceSources are defined for this type.
Group: Core
Size of this type is 96 bytes (on a 64-bit architecture).
Definition at line 2144 of file random-variable-stream.h.
ns3::BinomialRandomVariable::BinomialRandomVariable | ( | ) |
Definition at line 1762 of file random-variable-stream.cc.
References NS_LOG_FUNCTION.
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virtual |
Get the next random value drawn from the distribution.
Reimplemented from ns3::RandomVariableStream.
Definition at line 144 of file random-variable-stream.cc.
Get the next random value drawn from the distribution.
[in] | trials | Number of trials. |
[in] | probability | Probability of success in each trial. |
Definition at line 1792 of file random-variable-stream.cc.
References ns3::RandomVariableStream::GetStream(), GetValue(), and NS_LOG_DEBUG.
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static |
Register this type.
Definition at line 1742 of file random-variable-stream.cc.
References m_probability, m_trials, ns3::MakeDoubleAccessor(), ns3::MakeDoubleChecker(), ns3::MakeIntegerAccessor(), ns3::MakeIntegerChecker(), and ns3::TypeId::SetParent().
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overridevirtual |
Get the next random value drawn from the distribution.
Implements ns3::RandomVariableStream.
Definition at line 1801 of file random-variable-stream.cc.
References GetValue(), m_probability, and m_trials.
Referenced by GetInteger(), and GetValue().
Get the next random value drawn from the distribution.
[in] | trials | Number of trials. |
[in] | probability | Probability of success in each trial. |
Definition at line 1769 of file random-variable-stream.cc.
References ns3::RandomVariableStream::GetStream(), ns3::RandomVariableStream::IsAntithetic(), NS_LOG_DEBUG, ns3::RandomVariableStream::Peek(), and ns3::RngStream::RandU01().
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private |
The probability of success in each trial.
Definition at line 2179 of file random-variable-stream.h.
Referenced by GetTypeId(), and GetValue().
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private |
The number of trials.
Definition at line 2176 of file random-variable-stream.h.
Referenced by GetTypeId(), and GetValue().