org.openscience.cdk.math

Class RandomNumbersTool

java.lang.Object

java.util.Random

org.openscience.cdk.math.RandomNumbersTool

All Implemented Interfaces:

Serializable

public class RandomNumbersTool
extends Random

Class supplying useful methods to generate random numbers. This class isn't supposed to be instantiated. You should use it by calling its static methods.

See Also:

Serialized Form

Source code:

master

Belongs to CDK module:

standard

Constructor Summary

Constructors

Constructor and Description
RandomNumbersTool()

Method Summary

Modifier and Type	Method and Description
static double	exponentialDouble(double mean) Generates a random double from an Exponential distribution with the specified mean value.
static boolean	flipCoin(double p) Returns a boolean value based on a biased coin toss.
static double	gaussianDouble(double dev) Generates a random double from a Gaussian distribution with the specified deviation.
static float	gaussianFloat(float dev) Generates a random float from a Gaussian distribution with the specified deviation.
static Random	getRandom() Returns the instance of Random used by this class.
static long	getRandomSeed() Returns the seed being used by this random number generator.
static int	randomBit() Generates a random bit: either 0 or 1.
static boolean	randomBoolean() Generates a random boolean.
static double	randomDouble() Generates a random double between 0 and 1.
static double	randomDouble(double lo, double hi) Generates a random double between the specified values.
static float	randomFloat() Generates a random float between 0 and 1.
static float	randomFloat(float lo, float hi) Generates a random float between the specified values.
static int	randomInt() Generates a random integer between 0 and 1.
static int	randomInt(int lo, int hi) Generates a random integer between the specified values.
static long	randomLong() Generates a random long between 0 and 1.
static long	randomLong(long lo, long hi) Generates a random long between the specified values.
static void	setRandom(Random base_random) Sets the base generator to be used by this class.
static void	setRandomSeed(long new_seed) Sets the seed of this random number generator using a single long seed.

Methods inherited from class java.util.Random

doubles, doubles, doubles, doubles, ints, ints, ints, ints, longs, longs, longs, longs, next, nextBoolean, nextBytes, nextDouble, nextFloat, nextGaussian, nextInt, nextInt, nextLong, setSeed

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RandomNumbersTool

public RandomNumbersTool()

Method Detail

setRandom

public static void setRandom(Random base_random)

Sets the base generator to be used by this class.

Parameters:

base_random - a java.util.Random subclass.

setRandomSeed

public static void setRandomSeed(long new_seed)

Sets the seed of this random number generator using a single long seed.

Parameters:

new_seed - the seed to be used by the random number generator.

getRandomSeed

public static long getRandomSeed()

Returns the seed being used by this random number generator.

Returns:

the long seed.

getRandom

public static Random getRandom()

Returns the instance of Random used by this class.

Returns:

An object of Random

randomInt

public static int randomInt()

Generates a random integer between 0 and 1.

Returns:

a random integer between 0 and 1.

randomInt

public static int randomInt(int lo,
                            int hi)

Generates a random integer between the specified values.

Parameters:

lo - the lower bound for the generated integer.

hi - the upper bound for the generated integer.

Returns:

a random integer between lo and hi.

randomLong

public static long randomLong()

Generates a random long between 0 and 1.

Returns:

a random long between 0 and 1.

randomLong

public static long randomLong(long lo,
                              long hi)

Generates a random long between the specified values.

Parameters:

lo - the lower bound for the generated long.

hi - the upper bound for the generated long.

Returns:

a random long between lo and hi.

randomFloat

public static float randomFloat()

Generates a random float between 0 and 1.

Returns:

a random float between 0 and 1.

randomFloat

public static float randomFloat(float lo,
                                float hi)

Generates a random float between the specified values.

Parameters:

lo - the lower bound for the generated float.

hi - the upper bound for the generated float.

Returns:

a random float between lo and hi.

randomDouble

public static double randomDouble()

Generates a random double between 0 and 1.

Returns:

a random double between 0 and 1.

randomDouble

public static double randomDouble(double lo,
                                  double hi)

Generates a random double between the specified values.

Parameters:

lo - the lower bound for the generated double.

hi - the upper bound for the generated double.

Returns:

a random double between lo and hi.

randomBoolean

public static boolean randomBoolean()

Generates a random boolean.

Returns:

a random boolean.

randomBit

public static int randomBit()

Generates a random bit: either 0 or 1.

Returns:

a random bit.

flipCoin

public static boolean flipCoin(double p)

Returns a boolean value based on a biased coin toss.

Parameters:

p - the probability of success.

Returns:

true if a success was found; false otherwise.

gaussianFloat

public static float gaussianFloat(float dev)

Generates a random float from a Gaussian distribution with the specified deviation.

Parameters:

dev - the desired deviation.

Returns:

a random float from a Gaussian distribution with deviation dev.

gaussianDouble

public static double gaussianDouble(double dev)

Generates a random double from a Gaussian distribution with the specified deviation.

Parameters:

dev - the desired deviation.

Returns:

a random double from a Gaussian distribution with deviation dev.

exponentialDouble

public static double exponentialDouble(double mean)

Generates a random double from an Exponential distribution with the specified mean value.

Parameters:

mean - the desired mean value.

Returns:

a random double from an Exponential distribution with mean value mean.