RandomDataGenerator (Hipparchus 1.7 API)

java.lang.Object
- org.hipparchus.random.RandomDataGenerator

All Implemented Interfaces:

Serializable, RandomGenerator
```
public class RandomDataGenerator
extends Object
implements RandomGenerator, Serializable
```
A class for generating random data.

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor and Description
`RandomDataGenerator()` Construct a RandomDataGenerator with a default RandomGenerator as its source of random data.
`RandomDataGenerator(long seed)` Construct a RandomDataGenerator with a default RandomGenerator as its source of random data, initialized with the given seed value.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`protected RandomGenerator`	`delegate()` Returns the backing delegate instance that methods are forwarded to.
`double`	`nextBeta(double alpha, double beta)` Returns the next pseudo-random beta-distributed value with the given shape and scale parameters.
`boolean`	`nextBoolean()` Returns the next pseudorandom, uniformly distributed `boolean` value from this random number generator's sequence.
`void`	`nextBytes(byte[] bytes)` Generates random bytes and places them into a user-supplied byte array.
`void`	`nextBytes(byte[] bytes, int offset, int length)` Generates random bytes and places them into a user-supplied byte array.
`int`	`nextDeviate(IntegerDistribution dist)` Returns a random deviate from the given distribution.
`double`	`nextDeviate(RealDistribution dist)` Returns a random deviate from the given distribution.
`int[]`	`nextDeviates(IntegerDistribution dist, int size)` Returns an array of random deviates from the given distribution.
`double[]`	`nextDeviates(RealDistribution dist, int size)` Returns an array of random deviates from the given distribution.
`double`	`nextDouble()` Returns the next pseudorandom, uniformly distributed `double` value between `0.0` and `1.0` from this random number generator's sequence.
`double`	`nextExponential(double mean)` Returns the next pseudo-random, exponentially distributed deviate.
`float`	`nextFloat()` Returns the next pseudorandom, uniformly distributed `float` value between `0.0` and `1.0` from this random number generator's sequence.
`double`	`nextGamma(double shape, double scale)` Returns the next pseudo-random gamma-distributed value with the given shape and scale parameters.
`double`	`nextGaussian()` Returns the next pseudorandom, Gaussian ("normally") distributed `double` value with mean `0.0` and standard deviation `1.0` from this random number generator's sequence.
`String`	`nextHexString(int len)` Generates a random string of hex characters of length `len`.
`int`	`nextInt()` Returns the next pseudorandom, uniformly distributed `int` value from this random number generator's sequence.
`int`	`nextInt(int n)` Returns a pseudorandom, uniformly distributed `int` value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.
`int`	`nextInt(int lower, int upper)` Returns a uniformly distributed random integer between lower and upper (inclusive).
`double`	`nextLogNormal(double shape, double scale)` Returns the next log-normally-distributed pseudo-random deviate.
`long`	`nextLong()` Returns the next pseudorandom, uniformly distributed `long` value from this random number generator's sequence.
`long`	`nextLong(long n)` Returns a pseudorandom, uniformly distributed `int` value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.
`long`	`nextLong(long lower, long upper)` Returns a uniformly distributed random long integer between lower and upper (inclusive).
`double`	`nextNormal(double mean, double standardDeviation)` Returns the next normally-distributed pseudo-random deviate.
`int[]`	`nextPermutation(int n, int k)` Generates an integer array of length `k` whose entries are selected randomly, without repetition, from the integers `0, ..., n - 1` (inclusive).
`int`	`nextPoisson(double mean)` Returns a poisson-distributed deviate with the given mean.
`Object[]`	`nextSample(Collection<?> c, int k)` Returns an array of `k` objects selected randomly from the Collection `c`.
`double[]`	`nextSample(double[] a, int k)` Returns an array of `k` double values selected randomly from the double array `a`.
`int[]`	`nextSampleWithReplacement(int sampleSize, double[] weights)` Generates a random sample of size sampleSize from {0, 1, ...
`double`	`nextUniform(double lower, double upper)` Returns a double value uniformly distributed over [lower, upper]
`int`	`nextZipf(int numberOfElements, double exponent)` Returns an integer value following a Zipf distribution with the given parameter.
`static RandomDataGenerator`	`of(RandomGenerator randomGenerator)` Factory method to create a `RandomData` instance using the supplied `RandomGenerator`.
`void`	`setSeed(int seed)` Sets the seed of the underlying random number generator using an `int` seed.
`void`	`setSeed(int[] seed)` Sets the seed of the underlying random number generator using an `int` array seed.
`void`	`setSeed(long seed)` Sets the seed of the underlying random number generator using a `long` seed.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.hipparchus.random.RandomGenerator
nextBoolean, nextBytes, nextBytes, nextDouble, nextFloat, nextGaussian, nextInt, nextInt, nextLong, nextLong, setSeed, setSeed, setSeed

- Constructor Detail
  - RandomDataGenerator
```
public RandomDataGenerator()
```
    Construct a RandomDataGenerator with a default RandomGenerator as its source of random data.
  - RandomDataGenerator
```
public RandomDataGenerator(long seed)
```
    Construct a RandomDataGenerator with a default RandomGenerator as its source of random data, initialized with the given seed value.
    
    Parameters:
    
    seed - seed value
- Method Detail
  - of
```
public static RandomDataGenerator of(RandomGenerator randomGenerator)
```
    Factory method to create a RandomData instance using the supplied RandomGenerator.
    
    Parameters:
    
    randomGenerator - source of random bits
    
    Returns:
    
    a RandomData using the given RandomGenerator to source bits
    
    Throws:
    
    MathIllegalArgumentException - if randomGenerator is null
  - delegate
```
protected RandomGenerator delegate()
```
    Returns the backing delegate instance that methods are forwarded to.
    Concrete subclasses override this method to supply the instance being decorated.
    
    Returns:
    
    the delegate instance
  - nextBeta
```
public double nextBeta(double alpha,
                       double beta)
```
    Returns the next pseudo-random beta-distributed value with the given shape and scale parameters.
    
    Parameters:
    
    alpha - First shape parameter (must be positive).
    
    beta - Second shape parameter (must be positive).
    
    Returns:
    
    beta-distributed random deviate
  - nextExponential
```
public double nextExponential(double mean)
```
    Returns the next pseudo-random, exponentially distributed deviate.
    
    Parameters:
    
    mean - mean of the exponential distribution
    
    Returns:
    
    exponentially distributed deviate about the given mean
  - nextGamma
```
public double nextGamma(double shape,
                        double scale)
```
    Returns the next pseudo-random gamma-distributed value with the given shape and scale parameters.
    
    Parameters:
    
    shape - shape parameter of the distribution
    
    scale - scale parameter of the distribution
    
    Returns:
    
    gamma-distributed random deviate
  - nextNormal
```
public double nextNormal(double mean,
                         double standardDeviation)
```
    Returns the next normally-distributed pseudo-random deviate.
    
    Parameters:
    
    mean - mean of the normal distribution
    
    standardDeviation - standard deviation of the normal distribution
    
    Returns:
    
    a random value, normally distributed with the given mean and standard deviation
  - nextLogNormal
```
public double nextLogNormal(double shape,
                            double scale)
```
    Returns the next log-normally-distributed pseudo-random deviate.
    
    Parameters:
    
    shape - shape parameter of the log-normal distribution
    
    scale - scale parameter of the log-normal distribution
    
    Returns:
    
    a random value, normally distributed with the given mean and standard deviation
  - nextPoisson
```
public int nextPoisson(double mean)
```
    Returns a poisson-distributed deviate with the given mean.
    
    Parameters:
    
    mean - expected value
    
    Returns:
    
    poisson deviate
    
    Throws:
    
    MathIllegalArgumentException - if mean is not strictly positive
  - nextDeviate
```
public double nextDeviate(RealDistribution dist)
```
    Returns a random deviate from the given distribution.
    
    Parameters:
    
    dist - the distribution to sample from
    
    Returns:
    
    a random value following the given distribution
  - nextDeviates
```
public double[] nextDeviates(RealDistribution dist,
                             int size)
```
    Returns an array of random deviates from the given distribution.
    
    Parameters:
    
    dist - the distribution to sample from
    
    size - the number of values to return
    
    Returns:
    
    an array of size values following the given distribution
  - nextDeviate
```
public int nextDeviate(IntegerDistribution dist)
```
    Returns a random deviate from the given distribution.
    
    Parameters:
    
    dist - the distribution to sample from
    
    Returns:
    
    a random value following the given distribution
  - nextDeviates
```
public int[] nextDeviates(IntegerDistribution dist,
                          int size)
```
    Returns an array of random deviates from the given distribution.
    
    Parameters:
    
    dist - the distribution to sample from
    
    size - the number of values to return
    
    Returns:
    
    an array of size values following the given distribution
  - nextInt
```
public int nextInt(int lower,
                   int upper)
```
    Returns a uniformly distributed random integer between lower and upper (inclusive).
    
    Parameters:
    
    lower - lower bound for the generated value
    
    upper - upper bound for the generated value
    
    Returns:
    
    a random integer value within the given bounds
    
    Throws:
    
    MathIllegalArgumentException - if lower is not strictly less than or equal to upper
  - nextLong
```
public long nextLong(long lower,
                     long upper)
              throws MathIllegalArgumentException
```
    Returns a uniformly distributed random long integer between lower and upper (inclusive).
    
    Parameters:
    
    lower - lower bound for the generated value
    
    upper - upper bound for the generated value
    
    Returns:
    
    a random long integer value within the given bounds
    
    Throws:
    
    MathIllegalArgumentException - if lower is not strictly less than or equal to upper
  - nextUniform
```
public double nextUniform(double lower,
                          double upper)
```
    Returns a double value uniformly distributed over [lower, upper]
    
    Parameters:
    
    lower - lower bound
    
    upper - upper bound
    
    Returns:
    
    uniform deviate
    
    Throws:
    
    MathIllegalArgumentException - if upper is less than or equal to upper
  - nextZipf
```
public int nextZipf(int numberOfElements,
                    double exponent)
```
    Returns an integer value following a Zipf distribution with the given parameter.
    
    Parameters:
    
    numberOfElements - number of elements of the distribution
    
    exponent - exponent of the distribution
    
    Returns:
    
    random Zipf value
  - nextHexString
```
public String nextHexString(int len)
                     throws MathIllegalArgumentException
```
    Generates a random string of hex characters of length len.
    The generated string will be random, but not cryptographically secure.
    Algorithm Description: hex strings are generated using a 2-step process.
    1. len / 2 + 1 binary bytes are generated using the underlying Random
    2. Each binary byte is translated into 2 hex digits
    Parameters:
    
    len - the desired string length.
    
    Returns:
    
    the random string.
    
    Throws:
    
    MathIllegalArgumentException - if len <= 0.
  - nextPermutation
```
public int[] nextPermutation(int n,
                             int k)
                      throws MathIllegalArgumentException
```
    Generates an integer array of length k whose entries are selected randomly, without repetition, from the integers 0, ..., n - 1 (inclusive).
    Generated arrays represent permutations of n taken k at a time.
    This method calls MathArrays.shuffle in order to create a random shuffle of the set of natural numbers { 0, 1, ..., n - 1 }.
    
    Parameters:
    
    n - the domain of the permutation
    
    k - the size of the permutation
    
    Returns:
    
    a random k-permutation of n, as an array of integers
    
    Throws:
    
    MathIllegalArgumentException - if k > n.
    
    MathIllegalArgumentException - if k <= 0.
  - nextSample
```
public Object[] nextSample(Collection<?> c,
                           int k)
                    throws MathIllegalArgumentException
```
    Returns an array of k objects selected randomly from the Collection c.
    Sampling from c is without replacement; but if c contains identical objects, the sample may include repeats. If all elements of c are distinct, the resulting object array represents a Simple Random Sample of size k from the elements of c.
    
    This method calls nextPermutation(c.size(), k) in order to sample the collection.
    
    Parameters:
    
    c - the collection to be sampled
    
    k - the size of the sample
    
    Returns:
    
    a random sample of k elements from c
    
    Throws:
    
    MathIllegalArgumentException - if k > c.size().
    
    MathIllegalArgumentException - if k <= 0.
  - nextSample
```
public double[] nextSample(double[] a,
                           int k)
                    throws MathIllegalArgumentException
```
    Returns an array of k double values selected randomly from the double array a.
    Sampling from a is without replacement; but if a contains identical objects, the sample may include repeats. If all elements of a are distinct, the resulting object array represents a Simple Random Sample of size k from the elements of a.
    
    Parameters:
    
    a - the array to be sampled
    
    k - the size of the sample
    
    Returns:
    
    a random sample of k elements from a
    
    Throws:
    
    MathIllegalArgumentException - if k > c.size().
    
    MathIllegalArgumentException - if k <= 0.
  - nextSampleWithReplacement
```
public int[] nextSampleWithReplacement(int sampleSize,
                                       double[] weights)
```
    Generates a random sample of size sampleSize from {0, 1, ... , weights.length - 1}, using weights as probabilities.
    For 0 < i < weights.length, the probability that i is selected (on any draw) is weights[i]. If necessary, the weights array is normalized to sum to 1 so that weights[i] is a probability and the array sums to 1.
    Weights can be 0, but must not be negative, infinite or NaN. At least one weight must be positive.
    
    Parameters:
    
    sampleSize - size of sample to generate
    
    weights - probability sampling weights
    
    Returns:
    
    an array of integers between 0 and weights.length - 1
    
    Throws:
    
    MathIllegalArgumentException - if weights contains negative, NaN or infinite values or only 0s or sampleSize is less than 0
  - setSeed
```
public void setSeed(int seed)
```
    Sets the seed of the underlying random number generator using an int seed.
    Sequences of values generated starting with the same seeds should be identical.
    
    Specified by:
    
    setSeed in interface RandomGenerator
    
    Parameters:
    
    seed - the seed value
  - setSeed
```
public void setSeed(int[] seed)
```
    Sets the seed of the underlying random number generator using an int array seed.
    Sequences of values generated starting with the same seeds should be identical.
    
    Specified by:
    
    setSeed in interface RandomGenerator
    
    Parameters:
    
    seed - the seed value
  - setSeed
```
public void setSeed(long seed)
```
    Sets the seed of the underlying random number generator using a long seed.
    Sequences of values generated starting with the same seeds should be identical.
    
    Specified by:
    
    setSeed in interface RandomGenerator
    
    Parameters:
    
    seed - the seed value
  - nextBytes
```
public void nextBytes(byte[] bytes)
```
    Generates random bytes and places them into a user-supplied byte array. The number of random bytes produced is equal to the length of the byte array.
    
    Specified by:
    
    nextBytes in interface RandomGenerator
    
    Parameters:
    
    bytes - the non-null byte array in which to put the random bytes
  - nextBytes
```
public void nextBytes(byte[] bytes,
                      int offset,
                      int length)
```
    Generates random bytes and places them into a user-supplied byte array.
    
    Specified by:
    
    nextBytes in interface RandomGenerator
    
    Parameters:
    
    bytes - the non-null byte array in which to put the random bytes
    
    offset - the starting index for inserting the generated bytes into the array
    
    length - the number of bytes to generate
  - nextInt
```
public int nextInt()
```
    Returns the next pseudorandom, uniformly distributed int value from this random number generator's sequence.
    All 2³² possible int values should be produced with (approximately) equal probability.
    
    Specified by:
    
    nextInt in interface RandomGenerator
    
    Returns:
    
    the next pseudorandom, uniformly distributed int value from this random number generator's sequence
  - nextInt
```
public int nextInt(int n)
```
    Returns a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.
    
    Specified by:
    
    nextInt in interface RandomGenerator
    
    Parameters:
    
    n - the bound on the random number to be returned. Must be positive.
    
    Returns:
    
    a pseudorandom, uniformly distributed int value between 0 (inclusive) and n (exclusive).
  - nextLong
```
public long nextLong()
```
    Returns the next pseudorandom, uniformly distributed long value from this random number generator's sequence. All 2⁶⁴ possible long values should be produced with (approximately) equal probability.
    
    Specified by:
    
    nextLong in interface RandomGenerator
    
    Returns:
    
    the next pseudorandom, uniformly distributed long value from this random number generator's sequence
  - nextLong
```
public long nextLong(long n)
```
    Returns a pseudorandom, uniformly distributed int value between 0 (inclusive) and the specified value (exclusive), drawn from this random number generator's sequence.
    
    Specified by:
    
    nextLong in interface RandomGenerator
    
    Parameters:
    
    n - the bound on the random number to be returned. Must be positive.
    
    Returns:
    
    a pseudorandom, uniformly distributed int value between 0 (inclusive) and n (exclusive).
  - nextBoolean
```
public boolean nextBoolean()
```
    Returns the next pseudorandom, uniformly distributed boolean value from this random number generator's sequence.
    
    Specified by:
    
    nextBoolean in interface RandomGenerator
    
    Returns:
    
    the next pseudorandom, uniformly distributed boolean value from this random number generator's sequence
  - nextFloat
```
public float nextFloat()
```
    Returns the next pseudorandom, uniformly distributed float value between 0.0 and 1.0 from this random number generator's sequence.
    
    Specified by:
    
    nextFloat in interface RandomGenerator
    
    Returns:
    
    the next pseudorandom, uniformly distributed float value between 0.0 and 1.0 from this random number generator's sequence
  - nextDouble
```
public double nextDouble()
```
    Returns the next pseudorandom, uniformly distributed double value between 0.0 and 1.0 from this random number generator's sequence.
    
    Specified by:
    
    nextDouble in interface RandomGenerator
    
    Returns:
    
    the next pseudorandom, uniformly distributed double value between 0.0 and 1.0 from this random number generator's sequence
  - nextGaussian
```
public double nextGaussian()
```
    Returns the next pseudorandom, Gaussian ("normally") distributed double value with mean 0.0 and standard deviation 1.0 from this random number generator's sequence.
    
    Specified by:
    
    nextGaussian in interface RandomGenerator
    
    Returns:
    
    the next pseudorandom, Gaussian ("normally") distributed double value with mean 0.0 and standard deviation 1.0 from this random number generator's sequence

Class RandomDataGenerator

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.hipparchus.random.RandomGenerator

Constructor Detail

RandomDataGenerator

RandomDataGenerator

Method Detail

of

delegate

nextBeta

nextExponential

nextGamma

nextNormal

nextLogNormal

nextPoisson

nextDeviate

nextDeviates

nextDeviate

nextDeviates

nextInt

nextLong

nextUniform

nextZipf

nextHexString

nextPermutation

nextSample

nextSample

nextSampleWithReplacement

setSeed

setSeed

setSeed

nextBytes

nextBytes

nextInt

nextInt

nextLong

nextLong

nextBoolean

nextFloat

nextDouble

nextGaussian