private FDistribution()

in commons-statistics-distribution/src/main/java/org/apache/commons/statistics/distribution/FDistribution.java [65:89]

• 24 lines of code
• 3 McCabe index (conditional complexity)

    private FDistribution(double numeratorDegreesOfFreedom,
                          double denominatorDegreesOfFreedom) {
        this.numeratorDegreesOfFreedom = numeratorDegreesOfFreedom;
        this.denominatorDegreesOfFreedom = denominatorDegreesOfFreedom;
        final double nhalf = numeratorDegreesOfFreedom / 2;
        final double mhalf = denominatorDegreesOfFreedom / 2;
        nHalfLogNmHalfLogM = nhalf * Math.log(numeratorDegreesOfFreedom) +
                             mhalf * Math.log(denominatorDegreesOfFreedom);
        logBetaNhalfMhalf = LogBeta.value(nhalf, mhalf);

        if (denominatorDegreesOfFreedom > MIN_DENOMINATOR_DF_FOR_MEAN) {
            mean = denominatorDegreesOfFreedom / (denominatorDegreesOfFreedom - 2);
        } else {
            mean = Double.NaN;
        }
        if (denominatorDegreesOfFreedom > MIN_DENOMINATOR_DF_FOR_VARIANCE) {
            final double denomDFMinusTwo = denominatorDegreesOfFreedom - 2;
            variance = (2 * (denominatorDegreesOfFreedom * denominatorDegreesOfFreedom) *
                            (numeratorDegreesOfFreedom + denominatorDegreesOfFreedom - 2)) /
                       (numeratorDegreesOfFreedom * (denomDFMinusTwo * denomDFMinusTwo) *
                            (denominatorDegreesOfFreedom - 4));
        } else {
            variance = Double.NaN;
        }
    }