object.common
Class HypDistanceCalculator

java.lang.Object
  object.common.HypDistanceCalculator

public class HypDistanceCalculator
extends java.lang.Object

This class calculates cumulative Hypergeometric distances, used for p-value calculations.

Field Summary

static int	ROUNDING_STRATEGY The rounding strategy for the calculations.
static int	SCALE The number of digits after the first non-zero digit in the decimal part of a number.

Constructor Summary

HypDistanceCalculator()

Method Summary

protected static int	approximateScale(java.math.BigDecimal divisor, java.math.BigDecimal dividend)
static double	calculateHypDistance(int population, int population_true, int sample, int sample_true, boolean fast)
static java.math.BigDecimal	combinations(int n, int k)

Methods inherited from class java.lang.Object

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

Field Detail

SCALE

public static final int SCALE

The number of digits after the first non-zero digit in the decimal part of a number. This is used for division calculations.

See Also:

Constant Field Values

ROUNDING_STRATEGY

public static final int ROUNDING_STRATEGY

The rounding strategy for the calculations. The options are described in java.math.BigDecimal.

See Also:

Constant Field Values

Constructor Detail

HypDistanceCalculator

public HypDistanceCalculator()

Method Detail

calculateHypDistance

public static double calculateHypDistance(int population,
                                          int population_true,
                                          int sample,
                                          int sample_true,
                                          boolean fast)

Parameters:

population - the total population

population_true - the population that is true

sample - the sample size

sample_true - the items in sample that are in population_true

fast - whether the calculation should be done fast, at expense of some precision

Returns:

the hypergeometric distance for the given parameters

approximateScale

protected static int approximateScale(java.math.BigDecimal divisor,
                                      java.math.BigDecimal dividend)

combinations

public static java.math.BigDecimal combinations(int n,
                                                int k)

Returns:

n choose k