[Java] How to compute variance and standard deviation via Java

Problem
Assume I have a List of double, I would like to compute its variance and standard deviation.

How to implement it with Java?

How-To
Here has sample code:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

public static void main(String[] args) { List<Double> data = Arrays.asList(0.51, 0.53, 0.49, 0.74, 0.55, 0.47, 0.59, 0.47, 0.45, 0.72); DoubleSummaryStatistics summaryStatistics = data.stream().mapToDouble(d -> d.doubleValue()).summaryStatistics(); Double mean = summaryStatistics.getAverage(); Double variance = 0d; for (Double num : data) { variance += Math.pow(num - mean, 2); } variance = variance / 10; Double standardDeviation = Math.sqrt(variance); DecimalFormat df = new DecimalFormat("0.000"); log.info("variance = " + df.format(variance)); log.info("standardDeviation = " + df.format(standardDeviation)); }