SSJ  3.3.1
Stochastic Simulation in Java
Public Member Functions | Static Public Member Functions | List of all members
NormalDistQuick Class Reference

A variant of the class NormalDist (for the normal distribution with mean \(\mu\) and variance \(\sigma^2\)). More...

Inheritance diagram for NormalDistQuick:
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Collaboration diagram for NormalDistQuick:
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Public Member Functions

 NormalDistQuick ()
 Constructs a NormalDistQuick object with default parameters \(\mu= 0\) and \(\sigma= 1\).
 
 NormalDistQuick (double mu, double sigma)
 Constructs a NormalDistQuick object with mean \(\mu\) = mu and standard deviation \(\sigma\) = sigma.
 
double cdf (double x)
 Returns the distribution function \(F(x)\). More...
 
double barF (double x)
 Returns \(\bar{F}(x) = 1 - F(x)\). More...
 
double inverseF (double u)
 Returns the inverse distribution function \(F^{-1}(u)\), defined in ( inverseF ). More...
 
- Public Member Functions inherited from NormalDist
 NormalDist ()
 Constructs a NormalDist object with default parameters \(\mu= 0\) and \(\sigma= 1\).
 
 NormalDist (double mu, double sigma)
 Constructs a NormalDist object with mean \(\mu\) = mu and standard deviation \(\sigma\) = sigma.
 
double density (double x)
 
double cdf (double x)
 Returns the distribution function \(F(x)\). More...
 
double barF (double x)
 Returns \(\bar{F}(x) = 1 - F(x)\). More...
 
double inverseF (double u)
 Returns the inverse distribution function \(F^{-1}(u)\), defined in ( inverseF ). More...
 
double getMean ()
 Returns the mean of the distribution function.
 
double getVariance ()
 Returns the variance of the distribution function.
 
double getStandardDeviation ()
 Returns the standard deviation of the distribution function.
 
double getMu ()
 Returns the parameter \(\mu\).
 
double getSigma ()
 Returns the parameter \(\sigma\).
 
void setParams (double mu, double sigma)
 Sets the parameters \(\mu\) and \(\sigma\) of this object.
 
double [] getParams ()
 Return a table containing the parameters of the current distribution. More...
 
String toString ()
 Returns a String containing information about the current distribution.
 
- Public Member Functions inherited from ContinuousDistribution
abstract double density (double x)
 Returns \(f(x)\), the density evaluated at \(x\). More...
 
double barF (double x)
 Returns the complementary distribution function. More...
 
double inverseBrent (double a, double b, double u, double tol)
 Computes the inverse distribution function \(x = F^{-1}(u)\), using the Brent-Dekker method. More...
 
double inverseBisection (double u)
 Computes and returns the inverse distribution function \(x = F^{-1}(u)\), using bisection. More...
 
double inverseF (double u)
 Returns the inverse distribution function \(x = F^{-1}(u)\). More...
 
double getMean ()
 Returns the mean. More...
 
double getVariance ()
 Returns the variance. More...
 
double getStandardDeviation ()
 Returns the standard deviation. More...
 
double getXinf ()
 Returns \(x_a\) such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). More...
 
double getXsup ()
 Returns \(x_b\) such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). More...
 
void setXinf (double xa)
 Sets the value \(x_a=\) xa, such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). More...
 
void setXsup (double xb)
 Sets the value \(x_b=\) xb, such that the probability density is 0 everywhere outside the interval \([x_a, x_b]\). More...
 

Static Public Member Functions

static double cdf01 (double x)
 Same as cdf(0.0, 1.0, x).
 
static double cdf (double mu, double sigma, double x)
 Returns an approximation of \(\Phi(x)\), where \(\Phi\) is the standard normal distribution function, with mean 0 and variance 1. More...
 
static double barF01 (double x)
 Same as barF(0.0, 1.0, x).
 
static double barF (double mu, double sigma, double x)
 Returns an approximation of \(1 - \Phi(x)\), where \(\Phi\) is the standard normal distribution function, with mean 0 and variance. More...
 
static double inverseF01 (double u)
 Same as inverseF(0.0, 1.0, u).
 
static double inverseF (double mu, double sigma, double u)
 Returns an approximation of \(\Phi^{-1}(u)\), where \(\Phi\) is the standard normal distribution function, with mean 0 and variance 1. More...
 
- Static Public Member Functions inherited from NormalDist
static double density01 (double x)
 Same as density(0, 1, x).
 
static double density (double mu, double sigma, double x)
 Computes the normal density function ( fnormal ).
 
static double cdf01 (double x)
 Same as cdf(0, 1, x).
 
static double cdf (double mu, double sigma, double x)
 Computes the normal distribution function with mean \(\mu\) and variance \(\sigma^2\). More...
 
static double barF01 (double x)
 Same as barF(0, 1, x).
 
static double barF (double mu, double sigma, double x)
 Computes the complementary normal distribution function \(\bar{F}(x) = 1 - \Phi((x-\mu)/\sigma)\), with mean \(\mu\) and variance \(\sigma^2\). More...
 
static double inverseF01 (double u)
 Same as inverseF(0, 1, u).
 
static double inverseF (double mu, double sigma, double u)
 Computes the inverse normal distribution function with mean \(\mu\) and variance \(\sigma^2\). More...
 
static double [] getMLE (double[] x, int n)
 Estimates the parameters \((\mu, \sigma)\) of the normal distribution using the maximum likelihood method, from the \(n\) observations \(x[i]\), \(i = 0, 1,…, n-1\). More...
 
static NormalDist getInstanceFromMLE (double[] x, int n)
 Creates a new instance of a normal distribution with parameters \(\mu\) and \(\sigma\) estimated using the maximum likelihood method based on the \(n\) observations \(x[i]\), \(i = 0, 1, …, n-1\). More...
 
static double getMean (double mu, double sigma)
 Computes and returns the mean \(E[X] = \mu\) of the normal distribution with parameters \(\mu\) and \(\sigma\). More...
 
static double getVariance (double mu, double sigma)
 Computes and returns the variance \(\mbox{Var}[X] = \sigma^2\) of the normal distribution with parameters \(\mu\) and \(\sigma\). More...
 
static double getStandardDeviation (double mu, double sigma)
 Computes and returns the standard deviation \(\sigma\) of the normal distribution with parameters \(\mu\) and \(\sigma\). More...
 

Additional Inherited Members

- Public Attributes inherited from ContinuousDistribution
int decPrec = 15
 
- Protected Attributes inherited from NormalDist
double mu
 
double sigma
 
- Protected Attributes inherited from ContinuousDistribution
double supportA = Double.NEGATIVE_INFINITY
 
double supportB = Double.POSITIVE_INFINITY
 
- Static Protected Attributes inherited from NormalDist
static final double RAC2PI = 2.50662827463100050
 
- Static Protected Attributes inherited from ContinuousDistribution
static final double XBIG = 100.0
 
static final double XBIGM = 1000.0
 
static final double [] EPSARRAY
 

Detailed Description

A variant of the class NormalDist (for the normal distribution with mean \(\mu\) and variance \(\sigma^2\)).

The difference is in the implementation of the methods cdf01, barF01 and inverseF01, which are faster but less accurate than those of the class NormalDist.

Member Function Documentation

◆ barF() [1/2]

double barF ( double  x)

Returns \(\bar{F}(x) = 1 - F(x)\).

Parameters
xvalue at which the complementary distribution function is evaluated
Returns
complementary distribution function evaluated at x

Implements Distribution.

◆ barF() [2/2]

static double barF ( double  mu,
double  sigma,
double  x 
)
static

Returns an approximation of \(1 - \Phi(x)\), where \(\Phi\) is the standard normal distribution function, with mean 0 and variance.

  1. Uses Marsaglia et al’s [174]  fast method with table lookups. Returns 15 decimal digits of precision. This method is approximately twice faster than NormalDist.barF.

◆ cdf() [1/2]

double cdf ( double  x)

Returns the distribution function \(F(x)\).

Parameters
xvalue at which the distribution function is evaluated
Returns
distribution function evaluated at x

Implements Distribution.

◆ cdf() [2/2]

static double cdf ( double  mu,
double  sigma,
double  x 
)
static

Returns an approximation of \(\Phi(x)\), where \(\Phi\) is the standard normal distribution function, with mean 0 and variance 1.

Uses Marsaglia et al’s [174]  fast method with table lookups. Returns 15 decimal digits of precision. This method is approximately 60% faster than NormalDist.cdf.

◆ inverseF() [1/2]

double inverseF ( double  u)

Returns the inverse distribution function \(F^{-1}(u)\), defined in ( inverseF ).

Parameters
uvalue in the interval \((0,1)\) for which the inverse distribution function is evaluated
Returns
the inverse distribution function evaluated at u

Implements Distribution.

◆ inverseF() [2/2]

static double inverseF ( double  mu,
double  sigma,
double  u 
)
static

Returns an approximation of \(\Phi^{-1}(u)\), where \(\Phi\) is the standard normal distribution function, with mean 0 and variance 1.

Uses the method of Marsaglia, Zaman, and Marsaglia [174] , with table lookups. Returns 6 decimal digits of precision. This method is approximately 20% faster than NormalDist.inverseF.


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