Java Code Examples for org.apache.commons.math3.stat.StatUtils#mean()

@Override
public Object doWork(Object value) throws IOException{
  if(null == value){
    throw new IOException(String.format(Locale.ROOT, "Unable to find %s(...) because the value is null", constructingFactory.getFunctionName(getClass())));
  }
  else if(value instanceof List){
    @SuppressWarnings({"unchecked"})
    List<Number> c = (List<Number>) value;
    double[] data = new double[c.size()];
    for(int i=0; i< c.size(); i++) {
      data[i] = c.get(i).doubleValue();
    }

    return StatUtils.mean(data);
  }
  else{
    throw new IOException(String.format(Locale.ROOT, "Unable to find %s(...) because the value is not a collection, instead a %s was found", constructingFactory.getFunctionName(getClass()), value.getClass().getSimpleName()));
  }
}
 

@Test
public void testSample() {
    final double[] values = { -2.0d, 2.0d, 4.0d, -2.0d, 22.0d, 11.0d, 3.0d, 14.0d, 5.0d };
    final int length = values.length;
    final double mean = StatUtils.mean(values); // 6.333...
    final SemiVariance sv = new SemiVariance();  // Default bias correction is true
    final double downsideSemiVariance = sv.evaluate(values); // Downside is the default
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {-2d, 2d, 4d, -2d, 3d, 5d}, mean) / (length - 1),
            downsideSemiVariance, 1E-14);

    sv.setVarianceDirection(SemiVariance.UPSIDE_VARIANCE);
    final double upsideSemiVariance = sv.evaluate(values);
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {22d, 11d, 14d}, mean) / (length - 1),
            upsideSemiVariance, 1E-14);

    // Verify that upper + lower semivariance against the mean sum to variance
    Assert.assertEquals(StatUtils.variance(values), downsideSemiVariance + upsideSemiVariance, 10e-12);
}
 

@Test
public void testSample() {
    final double[] values = { -2.0d, 2.0d, 4.0d, -2.0d, 22.0d, 11.0d, 3.0d, 14.0d, 5.0d };
    final int length = values.length;
    final double mean = StatUtils.mean(values); // 6.333...
    final SemiVariance sv = new SemiVariance();  // Default bias correction is true
    final double downsideSemiVariance = sv.evaluate(values); // Downside is the default
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {-2d, 2d, 4d, -2d, 3d, 5d}, mean) / (length - 1),
            downsideSemiVariance, 1E-14);

    sv.setVarianceDirection(SemiVariance.UPSIDE_VARIANCE);
    final double upsideSemiVariance = sv.evaluate(values);
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {22d, 11d, 14d}, mean) / (length - 1),
            upsideSemiVariance, 1E-14);

    // Verify that upper + lower semivariance against the mean sum to variance
    Assert.assertEquals(StatUtils.variance(values), downsideSemiVariance + upsideSemiVariance, 10e-12);
}
 

@Test
public void testSample() {
    final double[] values = { -2.0d, 2.0d, 4.0d, -2.0d, 22.0d, 11.0d, 3.0d, 14.0d, 5.0d };
    final int length = values.length;
    final double mean = StatUtils.mean(values); // 6.333...
    final SemiVariance sv = new SemiVariance();  // Default bias correction is true
    final double downsideSemiVariance = sv.evaluate(values); // Downside is the default
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {-2d, 2d, 4d, -2d, 3d, 5d}, mean) / (length - 1),
            downsideSemiVariance, 1E-14);

    sv.setVarianceDirection(SemiVariance.UPSIDE_VARIANCE);
    final double upsideSemiVariance = sv.evaluate(values);
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {22d, 11d, 14d}, mean) / (length - 1),
            upsideSemiVariance, 1E-14);

    // Verify that upper + lower semivariance against the mean sum to variance
    Assert.assertEquals(StatUtils.variance(values), downsideSemiVariance + upsideSemiVariance, 10e-12);
}
 

@Test
public void testSample() {
    final double[] values = { -2.0d, 2.0d, 4.0d, -2.0d, 22.0d, 11.0d, 3.0d, 14.0d, 5.0d };
    final int length = values.length;
    final double mean = StatUtils.mean(values); // 6.333...
    final SemiVariance sv = new SemiVariance();  // Default bias correction is true
    final double downsideSemiVariance = sv.evaluate(values); // Downside is the default
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {-2d, 2d, 4d, -2d, 3d, 5d}, mean) / (length - 1),
            downsideSemiVariance, 1E-14);

    sv.setVarianceDirection(SemiVariance.UPSIDE_VARIANCE);
    final double upsideSemiVariance = sv.evaluate(values);
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {22d, 11d, 14d}, mean) / (length - 1),
            upsideSemiVariance, 1E-14);

    // Verify that upper + lower semivariance against the mean sum to variance
    Assert.assertEquals(StatUtils.variance(values), downsideSemiVariance + upsideSemiVariance, 10e-12);
}
 

@Test
public void testSample() {
    final double[] values = { -2.0d, 2.0d, 4.0d, -2.0d, 22.0d, 11.0d, 3.0d, 14.0d, 5.0d };
    final int length = values.length;
    final double mean = StatUtils.mean(values); // 6.333...
    final SemiVariance sv = new SemiVariance();  // Default bias correction is true
    final double downsideSemiVariance = sv.evaluate(values); // Downside is the default
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {-2d, 2d, 4d, -2d, 3d, 5d}, mean) / (length - 1),
            downsideSemiVariance, 1E-14);

    sv.setVarianceDirection(SemiVariance.UPSIDE_VARIANCE);
    final double upsideSemiVariance = sv.evaluate(values);
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {22d, 11d, 14d}, mean) / (length - 1),
            upsideSemiVariance, 1E-14);

    // Verify that upper + lower semivariance against the mean sum to variance
    Assert.assertEquals(StatUtils.variance(values), downsideSemiVariance + upsideSemiVariance, 10e-12);
}
 

@Test
public void testSample() {
    final double[] values = { -2.0d, 2.0d, 4.0d, -2.0d, 22.0d, 11.0d, 3.0d, 14.0d, 5.0d };
    final int length = values.length;
    final double mean = StatUtils.mean(values); // 6.333...
    final SemiVariance sv = new SemiVariance();  // Default bias correction is true
    final double downsideSemiVariance = sv.evaluate(values); // Downside is the default
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {-2d, 2d, 4d, -2d, 3d, 5d}, mean) / (length - 1),
            downsideSemiVariance, 1E-14);

    sv.setVarianceDirection(SemiVariance.UPSIDE_VARIANCE);
    final double upsideSemiVariance = sv.evaluate(values);
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {22d, 11d, 14d}, mean) / (length - 1),
            upsideSemiVariance, 1E-14);

    // Verify that upper + lower semivariance against the mean sum to variance
    Assert.assertEquals(StatUtils.variance(values), downsideSemiVariance + upsideSemiVariance, 10e-12);
}
 

@Test
public void testSample() {
    final double[] values = { -2.0d, 2.0d, 4.0d, -2.0d, 22.0d, 11.0d, 3.0d, 14.0d, 5.0d };
    final int length = values.length;
    final double mean = StatUtils.mean(values); // 6.333...
    final SemiVariance sv = new SemiVariance();  // Default bias correction is true
    final double downsideSemiVariance = sv.evaluate(values); // Downside is the default
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {-2d, 2d, 4d, -2d, 3d, 5d}, mean) / (length - 1),
            downsideSemiVariance, 1E-14);

    sv.setVarianceDirection(SemiVariance.UPSIDE_VARIANCE);
    final double upsideSemiVariance = sv.evaluate(values);
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {22d, 11d, 14d}, mean) / (length - 1),
            upsideSemiVariance, 1E-14);

    // Verify that upper + lower semivariance against the mean sum to variance
    Assert.assertEquals(StatUtils.variance(values), downsideSemiVariance + upsideSemiVariance, 10e-12);
}
 

@Test
public void testSample() {
    final double[] values = { -2.0d, 2.0d, 4.0d, -2.0d, 22.0d, 11.0d, 3.0d, 14.0d, 5.0d };
    final int length = values.length;
    final double mean = StatUtils.mean(values); // 6.333...
    final SemiVariance sv = new SemiVariance();  // Default bias correction is true
    final double downsideSemiVariance = sv.evaluate(values); // Downside is the default
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {-2d, 2d, 4d, -2d, 3d, 5d}, mean) / (length - 1),
            downsideSemiVariance, 1E-14);

    sv.setVarianceDirection(SemiVariance.UPSIDE_VARIANCE);
    final double upsideSemiVariance = sv.evaluate(values);
    Assert.assertEquals(TestUtils.sumSquareDev(new double[] {22d, 11d, 14d}, mean) / (length - 1),
            upsideSemiVariance, 1E-14);

    // Verify that upper + lower semivariance against the mean sum to variance
    Assert.assertEquals(StatUtils.variance(values), downsideSemiVariance + upsideSemiVariance, 10e-12);
}
 

/**
 * @param numForecastSteps
 *            number of values the forecaster is going to forecast
 *
 * @return Forecast Result
 */
@Override
public IForecastResult forecast(final int numForecastSteps) {
	final ITimeSeries<Double> history = this.getTsOriginal();
	final ITimeSeries<Double> tsFC = this.prepareForecastTS();

	final List<Double> allHistory = new ArrayList<Double>(history.getValues());
	final Double[] histValuesNotNull = MeanForecasterJava.removeNullValues(allHistory);
	final double mean = StatUtils.mean(ArrayUtils.toPrimitive(histValuesNotNull));
	final Double[] forecastValues = new Double[numForecastSteps];
	Arrays.fill(forecastValues, mean);

	tsFC.appendAll(forecastValues);
	return new ForecastResult(tsFC, this.getTsOriginal(), ForecastMethod.MEAN);
}
 

/**
 * 
 * @param dataActiveMap
 * @param sample
 */
public void calculateStats ( boolean[] dataActiveMap, double[] sample ) {
    ArrayList<Double> liveSample = new ArrayList<>();
    sampleMean = 0.0;

    if ( sample.length > 0 ) {

        for (int i = 0; i < sample.length; i ++) {
            if ( dataActiveMap[i] ) {
                sampleMean += sample[i];
                liveSample.add( sample[i] );
            }
        }

        sampleMean /= liveSample.size();
    }
    
    double[] liveSampleArray = new double[liveSample.size()];
    for (int i = 0; i < liveSampleArray.length; i ++){
        liveSampleArray[i] = (double)liveSample.get( i );
    }
    
           
    sampleMean = StatUtils.mean( liveSampleArray );
    variance = StatUtils.variance( liveSampleArray );

    stdErrSampleMean = Math.sqrt(variance) / Math.sqrt( liveSampleArray.length );

}
 

public double getMeanUMIPurity () {
	List<String> umis = new ArrayList<String>(this.umis());

	double [] purity = new double [umis.size()];
	for (int i=0; i<purity.length; i++) {
		double d = getUMIPurity(umis.get(i));
		purity[i]=d;
	}

	double result = StatUtils.mean(purity);
	return result;
}
 

@Override
public Double summarize(NumericColumn<?> column) {
  double[] col = removeMissing(column);
  return Math.sqrt(StatUtils.variance(col)) / StatUtils.mean(col);
}
 

@Override
public Double summarize(NumericColumn<?> column) {
  return StatUtils.mean(removeMissing(column));
}
 

@Override
public Double summarize(NumericColumn<?> column) {
  double[] col = removeMissing(column);
  return Math.sqrt(StatUtils.variance(col)) / StatUtils.mean(col);
}
 

@Override
public Double summarize(NumericColumn<?> column) {
  return StatUtils.mean(removeMissing(column));
}
 

public static double sharpe(double[] dailyReturns) {
    return StatUtils.mean(dailyReturns) / Math.sqrt(StatUtils.variance(dailyReturns)) * Math.sqrt(250);
}
 

/**
 * Calculates the mean of specified column
 * @param colName the column for which the mean will be calculated
 * @return mean
 */
public double mean(String colName) {
  return StatUtils.mean(toDoubleArray(colName));
}