Class UniformIntegerDistribution
java.lang.Object
org.hipparchus.distribution.discrete.AbstractIntegerDistribution
org.hipparchus.distribution.discrete.UniformIntegerDistribution
- All Implemented Interfaces:
Serializable
,IntegerDistribution
Implementation of the uniform integer distribution.
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Constructor Summary
ConstructorDescriptionUniformIntegerDistribution
(int lower, int upper) Creates a new uniform integer distribution using the given lower and upper bounds (both inclusive). -
Method Summary
Modifier and TypeMethodDescriptiondouble
cumulativeProbability
(int x) For a random variableX
whose values are distributed according to this distribution, this method returnsP(X <= x)
.double
Use this method to get the numerical value of the mean of this distribution.double
Use this method to get the numerical value of the variance of this distribution.int
Access the lower bound of the support.int
Access the upper bound of the support.boolean
Use this method to get information about whether the support is connected, i.e.double
probability
(int x) For a random variableX
whose values are distributed according to this distribution, this method returnsP(X = x)
.Methods inherited from class org.hipparchus.distribution.discrete.AbstractIntegerDistribution
inverseCumulativeProbability, logProbability, probability, solveInverseCumulativeProbability
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Constructor Details
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UniformIntegerDistribution
Creates a new uniform integer distribution using the given lower and upper bounds (both inclusive).- Parameters:
lower
- Lower bound (inclusive) of this distribution.upper
- Upper bound (inclusive) of this distribution.- Throws:
MathIllegalArgumentException
- iflower >= upper
.
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Method Details
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probability
public double probability(int x) For a random variableX
whose values are distributed according to this distribution, this method returnsP(X = x)
. In other words, this method represents the probability mass function (PMF) for the distribution.- Parameters:
x
- the point at which the PMF is evaluated- Returns:
- the value of the probability mass function at
x
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cumulativeProbability
public double cumulativeProbability(int x) For a random variableX
whose values are distributed according to this distribution, this method returnsP(X <= x)
. In other words, this method represents the (cumulative) distribution function (CDF) for this distribution.- Parameters:
x
- the point at which the CDF is evaluated- Returns:
- the probability that a random variable with this
distribution takes a value less than or equal to
x
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getNumericalMean
public double getNumericalMean()Use this method to get the numerical value of the mean of this distribution. For lower boundlower
and upper boundupper
, the mean is0.5 * (lower + upper)
.- Returns:
- the mean or
Double.NaN
if it is not defined
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getNumericalVariance
public double getNumericalVariance()Use this method to get the numerical value of the variance of this distribution. For lower boundlower
and upper boundupper
, andn = upper - lower + 1
, the variance is(n^2 - 1) / 12
.- Returns:
- the variance (possibly
Double.POSITIVE_INFINITY
orDouble.NaN
if it is not defined)
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getSupportLowerBound
public int getSupportLowerBound()Access the lower bound of the support. This method must return the same value asinverseCumulativeProbability(0)
. In other words, this method must return
The lower bound of the support is equal to the lower bound parameter of the distribution.inf {x in Z | P(X <= x) > 0}
.- Returns:
- lower bound of the support
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getSupportUpperBound
public int getSupportUpperBound()Access the upper bound of the support. This method must return the same value asinverseCumulativeProbability(1)
. In other words, this method must return
The upper bound of the support is equal to the upper bound parameter of the distribution.inf {x in R | P(X <= x) = 1}
.- Returns:
- upper bound of the support
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isSupportConnected
public boolean isSupportConnected()Use this method to get information about whether the support is connected, i.e. whether all integers between the lower and upper bound of the support are included in the support. The support of this distribution is connected.- Returns:
true
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