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Fixed missing javadoc.

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This commit is contained in:
Luc Maisonobe 2015-05-04 11:01:09 +02:00
parent b313ae6888
commit c8cb752431
2 changed files with 24 additions and 2 deletions
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14
src/main/java/org/apache/commons/math4/distribution/BetaDistribution.java
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@ -310,6 +310,11 @@ public class BetaDistribution extends AbstractRealDistribution {
/**
* Returns one sample using Cheng's BB algorithm, when both α and β are greater than 1.
* @param random random generator to use
* @param a0 distribution first shape parameter (α)
* @param a min(α, β) where α, β are the two distribution shape parameters
* @param b max(α, β) where α, β are the two distribution shape parameters
* @return sampled value
*/
private static double algorithmBB(RandomGenerator random,
final double a0,
@ -319,7 +324,9 @@ public class BetaDistribution extends AbstractRealDistribution {
final double beta = FastMath.sqrt((alpha - 2.) / (2. * a * b - alpha));
final double gamma = a + 1. / beta;
double r, w, t;
double r;
double w;
double t;
do {
final double u1 = random.nextDouble();
final double u2 = random.nextDouble();
@ -344,6 +351,11 @@ public class BetaDistribution extends AbstractRealDistribution {
/**
* Returns one sample using Cheng's BC algorithm, when at least one of α and β is smaller than 1.
* @param random random generator to use
* @param a0 distribution first shape parameter (α)
* @param a max(α, β) where α, β are the two distribution shape parameters
* @param b min(α, β) where α, β are the two distribution shape parameters
* @return sampled value
*/
private static double algorithmBC(RandomGenerator random,
final double a0,

12
src/main/java/org/apache/commons/math4/distribution/ZipfDistribution.java
View File

@ -307,11 +307,20 @@ public class ZipfDistribution extends AbstractIntegerDistribution {
/** Cached tail weight of instrumental distribution used for rejection sampling */
private double instrumentalDistributionTailWeight = Double.NaN;
/**
* Simple constructor.
* @param numberOfElements number of elements
* @param exponent exponent parameter of the distribution
*/
ZipfRejectionSampler(final int numberOfElements, final double exponent) {
this.numberOfElements = numberOfElements;
this.exponent = exponent;
}
/** Generate a random value sampled from this distribution.
* @param random random generator to use
* @return random value sampled from this distribution
*/
int sample(final RandomGenerator random) {
if (Double.isNaN(instrumentalDistributionTailWeight)) {
instrumentalDistributionTailWeight = integratePowerFunction(-exponent, 1.5, numberOfElements+0.5);
@ -360,7 +369,7 @@ public class ZipfDistribution extends AbstractIntegerDistribution {
* A Taylor series expansion is used, if x is close to 0.
*
* @param q a value in the range [0,1]
* @param
* @param x free parameter
* @return log((1-q)+q*exp(x))/x
*/
static double helper1(final double q, final double x) {
@ -377,6 +386,7 @@ public class ZipfDistribution extends AbstractIntegerDistribution {
* <p>
* A Taylor series expansion is used, if x is close to 0.
*
* @param x free parameter
* @return (exp(x)-1)/x if x is non-zero, 1 if x=0
*/
static double helper2(final double x) {