The Weibull distribution Random Number Generator (RNG) that allows stream numbers to be set deterministically. More...
#include <random-variable-stream.h>
Public Member Functions | |
WeibullRandomVariable () | |
Creates a Weibull distribution RNG with the default values for the scale, shape, and upper bound. More... | |
double | GetBound (void) const |
Returns the upper bound on values that can be returned by this RNG stream. More... | |
uint32_t | GetInteger (uint32_t scale, uint32_t shape, uint32_t bound) |
Returns a random unsigned integer from a Weibull distribution with the specified scale, shape, and upper bound. More... | |
virtual uint32_t | GetInteger (void) |
Returns a random unsigned integer from a Weibull distribution with the current scale, shape, and upper bound. More... | |
double | GetScale (void) const |
Returns the scale parameter for the Weibull distribution returned by this RNG stream. More... | |
double | GetShape (void) const |
Returns the shape parameter for the Weibull distribution returned by this RNG stream. More... | |
double | GetValue (double scale, double shape, double bound) |
Returns a random double from a Weibull distribution with the specified scale, shape, and upper bound. More... | |
virtual double | GetValue (void) |
Returns a random double from a Weibull distribution with the current scale, shape, and upper bound. More... | |
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RandomVariableStream () | |
virtual | ~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... | |
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Object () | |
virtual | ~Object () |
void | AggregateObject (Ptr< Object > other) |
void | Dispose (void) |
Run the DoDispose methods of this object and all the objects aggregated to it. More... | |
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) |
This method calls the virtual DoInitialize method on all the objects aggregated to this object. More... | |
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SimpleRefCount () | |
Constructor. More... | |
SimpleRefCount (const SimpleRefCount &o) | |
Copy constructor. More... | |
uint32_t | GetReferenceCount (void) const |
Get the reference count of the object. More... | |
SimpleRefCount & | operator= (const SimpleRefCount &o) |
Assignment. More... | |
void | Ref (void) const |
Increment the reference count. More... | |
void | Unref (void) const |
Decrement the reference count. More... | |
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virtual | ~ObjectBase () |
Virtual destructor. More... | |
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) |
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static TypeId | GetTypeId (void) |
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static TypeId | GetTypeId (void) |
Register this type. More... | |
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static void | Cleanup (void) |
Noop. More... | |
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static TypeId | GetTypeId (void) |
Get the type ID. More... | |
Private Attributes | |
double | m_bound |
The upper bound on values that can be returned by this RNG stream. More... | |
double | m_scale |
The scale parameter for the Weibull distribution returned by this RNG stream. More... | |
double | m_shape |
The shape parameter for the Weibull distribution returned by this RNG stream. More... | |
Additional Inherited Members | |
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RngStream * | Peek (void) const |
Returns a pointer to the underlying RNG stream. More... | |
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Object (const Object &o) | |
virtual void | DoDispose (void) |
This method is called by Object::Dispose or by the object's destructor, whichever comes first. More... | |
virtual void | DoInitialize (void) |
This method is called only once by Object::Initialize. More... | |
virtual void | NotifyNewAggregate (void) |
This method is invoked whenever two sets of objects are aggregated together. More... | |
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void | ConstructSelf (const AttributeConstructionList &attributes) |
virtual void | NotifyConstructionCompleted (void) |
This method is invoked once all member attributes have been initialized. More... | |
The Weibull 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 Weibull distribution. It also supports the generation of single random numbers from various Weibull distributions.
The probability density function is defined over the interval [0, ] as:
where
is the shape parameter and
is the scale parameter. The specified mean is related to the scale and shape parameters by the following relation:
where
is the Gamma function.
Since Weibull distributions can theoretically return unbounded values, it is sometimes useful to specify a fixed upper limit. Note however when the upper limit is specified, the true mean of the distribution is slightly smaller than the mean value specified.
Here is an example of how to use this class:
ns3::WeibullRandomVariable is accessible through the following paths with Config::Set and Config::Connect:
No TraceSources are defined for this type.
Definition at line 874 of file random-variable-stream.h.
ns3::WeibullRandomVariable::WeibullRandomVariable | ( | ) |
Creates a Weibull distribution RNG with the default values for the scale, shape, and upper bound.
Definition at line 562 of file random-variable-stream.cc.
References NS_LOG_FUNCTION.
double ns3::WeibullRandomVariable::GetBound | ( | void | ) | const |
Returns the upper bound on values that can be returned by this RNG stream.
Definition at line 582 of file random-variable-stream.cc.
References m_bound, and NS_LOG_FUNCTION.
uint32_t ns3::WeibullRandomVariable::GetInteger | ( | uint32_t | scale, |
uint32_t | shape, | ||
uint32_t | bound | ||
) |
Returns a random unsigned integer from a Weibull distribution with the specified scale, shape, and upper bound.
scale | Scale parameter for the Weibull distribution. |
shape | Shape parameter for the Weibull distribution. |
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 1.
Definition at line 613 of file random-variable-stream.cc.
References GetValue(), and NS_LOG_FUNCTION.
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virtual |
Returns a random unsigned integer from a Weibull distribution with the current scale, shape, and upper bound.
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 1.
Implements ns3::RandomVariableStream.
Definition at line 626 of file random-variable-stream.cc.
References GetValue(), m_bound, m_scale, m_shape, and NS_LOG_FUNCTION.
double ns3::WeibullRandomVariable::GetScale | ( | void | ) | const |
Returns the scale parameter for the Weibull distribution returned by this RNG stream.
Definition at line 570 of file random-variable-stream.cc.
References m_scale, and NS_LOG_FUNCTION.
double ns3::WeibullRandomVariable::GetShape | ( | void | ) | const |
Returns the shape parameter for the Weibull distribution returned by this RNG stream.
Definition at line 576 of file random-variable-stream.cc.
References m_shape, and NS_LOG_FUNCTION.
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static |
Definition at line 542 of file random-variable-stream.cc.
References m_bound, m_scale, m_shape, and ns3::TypeId::SetParent().
double ns3::WeibullRandomVariable::GetValue | ( | double | scale, |
double | shape, | ||
double | bound | ||
) |
Returns a random double from a Weibull distribution with the specified scale, shape, and upper bound.
scale | Scale parameter for the Weibull distribution. |
shape | Shape parameter for the Weibull distribution. |
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 1.
Definition at line 589 of file random-variable-stream.cc.
References ns3::RandomVariableStream::IsAntithetic(), NS_LOG_FUNCTION, ns3::RandomVariableStream::Peek(), and ns3::RngStream::RandU01().
Referenced by RandomVariableStreamWeibullTestCase::ChiSquaredTest(), RandomVariableStreamWeibullAntitheticTestCase::ChiSquaredTest(), RandomVariableStreamWeibullTestCase::DoRun(), and RandomVariableStreamWeibullAntitheticTestCase::DoRun().
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virtual |
Returns a random double from a Weibull distribution with the current scale, shape, and upper bound.
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 1.
Note that we have to re-implement this method here because the method is overloaded above for the three-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 620 of file random-variable-stream.cc.
References m_bound, m_scale, m_shape, and NS_LOG_FUNCTION.
Referenced by GetInteger().
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private |
The upper bound on values that can be returned by this RNG stream.
Definition at line 1018 of file random-variable-stream.h.
Referenced by GetBound(), GetInteger(), GetTypeId(), and GetValue().
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private |
The scale parameter for the Weibull distribution returned by this RNG stream.
Definition at line 1012 of file random-variable-stream.h.
Referenced by GetInteger(), GetScale(), GetTypeId(), and GetValue().
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private |
The shape parameter for the Weibull distribution returned by this RNG stream.
Definition at line 1015 of file random-variable-stream.h.
Referenced by GetInteger(), GetShape(), GetTypeId(), and GetValue().