A FloatGenerator which returns a normally distributed value. More...

#include <RandGenerator.h>

Inheritance diagram for Menge::Math::NormalFloatGenerator:

Public Member Functions
	NormalFloatGenerator (float mean, float stddev, float minVal, float maxVal, int seed=0)
	Constructor. More...

void	set (float mean, float stddev, float minVal, float maxVal)
	Sets the distribution parameters. More...

virtual float	getValue () const
	Return a value based on the float generation rules. More...

virtual float	getValueConcurrent () const
	Return a value based on the float generation rules - performed in a thread-safe manner. More...

virtual void	print (Logger &out) const
	Function for converting the generator to a string on a output stream. More...

virtual FloatGenerator *	copy () const
	Create a copy of itself. More...

Public Member Functions inherited from Menge::Math::FloatGenerator
	FloatGenerator ()
	Constructor.

virtual	~FloatGenerator ()
	Virtual destructor.

Protected Attributes
float	_mean
	The mean value of the distribution.

float	_std
	The standard deviation of the value.

float	_min
	The lower clamped value, such that all values returned will be greater than or equal to minVal. For largely "pure" normal distribution, minVal <= mean - 3 * stddev.

float	_max
	The upper clamped value, such that all values returned will be less than or equal to maxVal. For largely "pure" normal distribution, maxVal >= mean + 3 * stddev.

float	_second
	The second random number generated (see Math::r4_normalR).

unsigned int	_calls
	The number of calls to the generator. Every second call requires a new call to the random number generator.

int	_seed
	A seed for the random number generator.

SimpleLock	_lock
	The lock for guaranteeing threadsafe random number generation.

Friends
Logger &	operator<< (Logger &out, const NormalFloatGenerator &gen)
	Friend function for writing string representation to an output stream. More...

Detailed Description

A FloatGenerator which returns a normally distributed value.

Furthermore, the normally distributed value is clamped to a range [min, max] that prevents the otherwise theoretically possible (though highly improbable) values that can lie outside of practical ranges.

The min and max values should span a range which includes the interval: [ mean - 3 * std. dev., mean + 3 * std. dev.] Clamping the range smaller will lead to abnormal accretions of samples at the clamping boundaries. By having the range span at least six standard deviations, centered at the mean, most of the normal distribution will be unaffected by clamping.

Constructor & Destructor Documentation

Menge::Math::NormalFloatGenerator::NormalFloatGenerator	(	float	mean,
		float	stddev,
		float	minVal,
		float	maxVal,
		int	seed = `0`
	)

Constructor.

The value is normally distributed around mean, with a standard deviation of stddev but clamped to lie within the range [minVal, maxVal].

Parameters

mean	The mean value of the distribution.
stddev	The standard deviation of the value
minVal	The lower clamped value, such that all values returned will be greater than or equal to minVal. For largely "pure" normal distribution, minVal <= mean - 3 * stddev.
maxVal	The upper clamped value, such that all values returned will be less than or equal to maxVal. For largely "pure" normal distribution, maxVal >= mean + 3 * stddev.
seed	If the seed is zero, the global seed will be used otherwise the particular seed will be used.

Member Function Documentation

FloatGenerator * Menge::Math::NormalFloatGenerator::copy ( ) const

virtual

Create a copy of itself.

Returns: A pointer to a new generator which is a copy of this one. The caller of this function is responsible for freeing up the memory for the copy.

Implements Menge::Math::FloatGenerator.

float Menge::Math::NormalFloatGenerator::getValue ( ) const

virtual

Return a value based on the float generation rules.

Returns: A clamped, normally-distributed float value.

Implements Menge::Math::FloatGenerator.

float Menge::Math::NormalFloatGenerator::getValueConcurrent ( ) const

virtual

Return a value based on the float generation rules - performed in a thread-safe manner.

This is the basic functionality that must be overwridden by derived classes.

Returns: A float value.

Implements Menge::Math::FloatGenerator.

void Menge::Math::NormalFloatGenerator::print ( Logger & out ) const

virtual

Function for converting the generator to a string on a output stream.

Parameters

out	The output stream to write the string representation to.

Implements Menge::Math::FloatGenerator.

void Menge::Math::NormalFloatGenerator::set	(	float	mean,
		float	stddev,
		float	minVal,
		float	maxVal
	)

Sets the distribution parameters.

Parameters

mean	The mean value of the distribution.
stddev	The standard deviation of the value
minVal	The lower clamped value, such that all values returned will be greater than or equal to minVal. For largely "pure" normal distribution, minVal <= mean - 3 * stddev.
maxVal	The upper clamped value, such that all values returned will be less than or equal to maxVal. For largely "pure" normal distribution, maxVal >= mean + 3 * stddev.

Friends And Related Function Documentation

Logger& operator<<	(	Logger &	out,
		const NormalFloatGenerator &	gen
	)

friend

Friend function for writing string representation to an output stream.

Parameters

out	The output stream.
gen	An instance of the generator to represent as a string.

Returns: Reference to the input output stream.

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

src/menge/MengeCore/Math/RandGenerator.h
src/menge/MengeCore/Math/RandGenerator.cpp

Public Member Functions

Protected Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation