The Erlang distribution Random Number Generator (RNG) that allows stream numbers to be set deterministically. More...
#include "random-variable-stream.h"
Public Member Functions | |
ErlangRandomVariable () | |
Creates an Erlang distribution RNG with the default values for k and lambda. More... | |
uint32_t | GetInteger (uint32_t k, uint32_t lambda) |
Returns a random unsigned integer from an Erlang distribution with the specified k and lambda. More... | |
virtual uint32_t | GetInteger (void) |
Returns a random unsigned integer from an Erlang distribution with the current k and lambda. More... | |
uint32_t | GetK (void) const |
Returns the k value for the Erlang distribution returned by this RNG stream. More... | |
double | GetLambda (void) const |
Returns the lambda value for the Erlang distribution returned by this RNG stream. More... | |
double | GetValue (uint32_t k, double lambda) |
Returns a random double from an Erlang distribution with the specified k and lambda. More... | |
virtual double | GetValue (void) |
Returns a random double from an Erlang distribution with the current k and lambda. More... | |
Public Member Functions inherited from ns3::RandomVariableStream | |
RandomVariableStream () | |
Default constructor. More... | |
virtual | ~RandomVariableStream () |
Destructor. More... | |
int64_t | GetStream (void) const |
Returns the stream number for the RngStream. More... | |
bool | IsAntithetic (void) const |
Check if antithetic values will be generated. More... | |
void | SetAntithetic (bool isAntithetic) |
Specify whether antithetic values should be generated. More... | |
void | SetStream (int64_t stream) |
Specifies the stream number for the RngStream. More... | |
Public Member Functions inherited from ns3::Object | |
Object () | |
Constructor. More... | |
virtual | ~Object () |
Destructor. More... | |
void | AggregateObject (Ptr< Object > other) |
Aggregate two Objects together. More... | |
void | Dispose (void) |
Dispose of this Object. More... | |
AggregateIterator | GetAggregateIterator (void) const |
Get an iterator to the Objects aggregated to this one. More... | |
virtual TypeId | GetInstanceTypeId (void) const |
Get the most derived TypeId for this Object. More... | |
template<> | |
Ptr< Object > | GetObject () const |
Specialization of () for objects of type ns3::Object. More... | |
template<typename T > | |
Ptr< T > | GetObject (TypeId tid) const |
Get a pointer to the requested aggregated Object by TypeId. More... | |
template<> | |
Ptr< Object > | GetObject (TypeId tid) const |
Specialization of (TypeId tid) for objects of type ns3::Object. More... | |
template<typename T > | |
Ptr< T > | GetObject (void) const |
Get a pointer to the requested aggregated Object. More... | |
void | Initialize (void) |
Invoke DoInitialize on all Objects aggregated to this one. More... | |
bool | IsInitialized (void) const |
Check if the object has been initialized. More... | |
Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter > | |
SimpleRefCount () | |
Default constructor. More... | |
SimpleRefCount (const SimpleRefCount &o[[maybe_unused]]) | |
Copy constructor. More... | |
uint32_t | GetReferenceCount (void) const |
Get the reference count of the object. More... | |
SimpleRefCount & | operator= ([[maybe_unused]] const SimpleRefCount &o) |
Assignment operator. More... | |
void | Ref (void) const |
Increment the reference count. More... | |
void | Unref (void) const |
Decrement the reference count. More... | |
Public Member Functions inherited from ns3::ObjectBase | |
virtual | ~ObjectBase () |
Virtual destructor. More... | |
void | GetAttribute (std::string name, AttributeValue &value) const |
Get the value of an attribute, raising fatal errors if unsuccessful. More... | |
bool | GetAttributeFailSafe (std::string name, AttributeValue &value) const |
Get the value of an attribute without raising erros. More... | |
void | SetAttribute (std::string name, const AttributeValue &value) |
Set a single attribute, raising fatal errors if unsuccessful. More... | |
bool | SetAttributeFailSafe (std::string name, const AttributeValue &value) |
Set a single attribute without raising errors. More... | |
bool | TraceConnect (std::string name, std::string context, const CallbackBase &cb) |
Connect a TraceSource to a Callback with a context. More... | |
bool | TraceConnectWithoutContext (std::string name, const CallbackBase &cb) |
Connect a TraceSource to a Callback without a context. More... | |
bool | TraceDisconnect (std::string name, std::string context, const CallbackBase &cb) |
Disconnect from a TraceSource a Callback previously connected with a context. More... | |
bool | TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb) |
Disconnect from a TraceSource a Callback previously connected without a context. More... | |
Static Public Member Functions | |
static TypeId | GetTypeId (void) |
Register this type. More... | |
Static Public Member Functions inherited from ns3::RandomVariableStream | |
static TypeId | GetTypeId (void) |
Register this type. More... | |
Static Public Member Functions inherited from ns3::Object | |
static TypeId | GetTypeId (void) |
Register this type. More... | |
Static Public Member Functions inherited from ns3::ObjectBase | |
static TypeId | GetTypeId (void) |
Get the type ID. More... | |
Private Member Functions | |
double | GetExponentialValue (double mean, double bound) |
Returns a random double from an exponential distribution with the specified mean and upper bound. More... | |
Private Attributes | |
uint32_t | m_k |
The k value for the Erlang distribution returned by this RNG stream. More... | |
double | m_lambda |
The lambda value for the Erlang distribution returned by this RNG stream. More... | |
Additional Inherited Members | |
Protected Member Functions inherited from ns3::RandomVariableStream | |
RngStream * | Peek (void) const |
Get the pointer to the underlying RngStream. More... | |
Protected Member Functions inherited from ns3::Object | |
Object (const Object &o) | |
Copy an Object. More... | |
virtual void | DoDispose (void) |
Destructor implementation. More... | |
virtual void | DoInitialize (void) |
Initialize() implementation. More... | |
virtual void | NotifyNewAggregate (void) |
Notify all Objects aggregated to this one of a new Object being aggregated. More... | |
Protected Member Functions inherited from ns3::ObjectBase | |
void | ConstructSelf (const AttributeConstructionList &attributes) |
Complete construction of ObjectBase; invoked by derived classes. More... | |
virtual void | NotifyConstructionCompleted (void) |
Notifier called once the ObjectBase is fully constructed. More... | |
Related Functions inherited from ns3::ObjectBase | |
static TypeId | GetObjectIid (void) |
Ensure the TypeId for ObjectBase gets fully configured to anchor the inheritance tree properly. More... | |
The Erlang distribution Random Number Generator (RNG) that allows stream numbers to be set deterministically.
This class supports the creation of objects that return random numbers from a fixed Erlang distribution. It also supports the generation of single random numbers from various Erlang distributions.
The Erlang distribution is a special case of the Gamma distribution where k (= alpha) is a non-negative integer. Erlang distributed variables can be generated using a much faster algorithm than gamma variables.
The probability density function is defined over the interval [0, ) as: where and
Here is an example of how to use this class:
ns3::ErlangRandomVariable is accessible through the following paths with Config::Set and Config::Connect:
No TraceSources are defined for this type.
Size of this type is 72 bytes (on a 64-bit architecture).
Definition at line 1679 of file random-variable-stream.h.
ns3::ErlangRandomVariable::ErlangRandomVariable | ( | ) |
Creates an Erlang distribution RNG with the default values for k and lambda.
Definition at line 1085 of file random-variable-stream.cc.
References NS_LOG_FUNCTION.
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private |
Returns a random double from an exponential distribution with the specified mean and upper bound.
[in] | mean | Mean value of the random variables. |
[in] | bound | Upper bound on values returned. |
Note that antithetic values are being generated if m_isAntithetic is equal to true. If is a uniform variable over [0,1] and
is a value that would be returned normally, then ) is the distance that would be from . The value returned in the antithetic case, , is calculated as
which now involves the log of the distance is from the 1.
Definition at line 1154 of file random-variable-stream.cc.
References ns3::RandomVariableStream::IsAntithetic(), NS_LOG_FUNCTION, ns3::RandomVariableStream::Peek(), and ns3::RngStream::RandU01().
Referenced by GetValue().
uint32_t ns3::ErlangRandomVariable::GetInteger | ( | uint32_t | k, |
uint32_t | lambda | ||
) |
Returns a random unsigned integer from an Erlang distribution with the specified k and lambda.
[in] | k | K value for the Erlang distribution. |
[in] | lambda | Lambda value for the Erlang distribution. |
Note that antithetic values are being generated if m_isAntithetic is equal to true. If is a uniform variable over [0,1] and is a value that would be returned normally, then ) is the distance that would be from . The value returned in the antithetic case, , uses (1-u), which is the distance is from the 1.
Definition at line 1134 of file random-variable-stream.cc.
References GetValue(), bianchi11ax::k, and NS_LOG_FUNCTION.
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virtual |
Returns a random unsigned integer from an Erlang distribution with the current k and lambda.
Note that antithetic values are being generated if m_isAntithetic is equal to true. If is a uniform variable over [0,1] and is a value that would be returned normally, then ) is the distance that would be from . The value returned in the antithetic case, , uses (1-u), which is the distance is from the 1.
Implements ns3::RandomVariableStream.
Definition at line 1147 of file random-variable-stream.cc.
References GetValue(), m_k, m_lambda, and NS_LOG_FUNCTION.
uint32_t ns3::ErlangRandomVariable::GetK | ( | void | ) | const |
Returns the k value for the Erlang distribution returned by this RNG stream.
Definition at line 1092 of file random-variable-stream.cc.
References m_k, and NS_LOG_FUNCTION.
double ns3::ErlangRandomVariable::GetLambda | ( | void | ) | const |
Returns the lambda value for the Erlang distribution returned by this RNG stream.
Definition at line 1098 of file random-variable-stream.cc.
References m_lambda, and NS_LOG_FUNCTION.
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static |
Register this type.
Definition at line 1068 of file random-variable-stream.cc.
References m_k, m_lambda, ns3::MakeDoubleAccessor(), ns3::MakeIntegerAccessor(), and ns3::TypeId::SetParent().
double ns3::ErlangRandomVariable::GetValue | ( | uint32_t | k, |
double | lambda | ||
) |
Returns a random double from an Erlang distribution with the specified k and lambda.
[in] | k | K value for the Erlang distribution. |
[in] | lambda | Lambda value for the Erlang distribution. |
Note that antithetic values are being generated if m_isAntithetic is equal to true. If is a uniform variable over [0,1] and is a value that would be returned normally, then ) is the distance that would be from . The value returned in the antithetic case, , uses (1-u), which is the distance is from the 1.
Definition at line 1117 of file random-variable-stream.cc.
References GetExponentialValue(), bianchi11ax::k, NS_LOG_FUNCTION, and test-ns3::result.
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virtual |
Returns a random double from an Erlang distribution with the current k and lambda.
Note that antithetic values are being generated if m_isAntithetic is equal to true. If is a uniform variable over [0,1] and is a value that would be returned normally, then ) is the distance that would be from . The value returned in the antithetic case, , uses (1-u), which is the distance is from the 1.
Note that we have to re-implement this method here because the method is overloaded above for the two-argument variant and the c++ name resolution rules don't work well with overloads split between parent and child classes.
Implements ns3::RandomVariableStream.
Definition at line 1141 of file random-variable-stream.cc.
References m_k, m_lambda, and NS_LOG_FUNCTION.
Referenced by GetInteger().
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private |
The k value for the Erlang distribution returned by this RNG stream.
Definition at line 1795 of file random-variable-stream.h.
Referenced by GetInteger(), GetK(), GetTypeId(), and GetValue().
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private |
The lambda value for the Erlang distribution returned by this RNG stream.
Definition at line 1798 of file random-variable-stream.h.
Referenced by GetInteger(), GetLambda(), GetTypeId(), and GetValue().