for (int i = 0; i < size; i++) {
features[i] = expectedMean + random.nextGaussian() * stdDev;
}
// When
FixedStreamFeatureStatistics statistics = new FixedStreamFeatureStatistics();
for (int i = 0; i < size; i++) {
statistics.update(features[i]);
}
// Then
assertEquals(expectedMean, statistics.getMean(), 0.1);
assertEquals(stdDev, statistics.getStdDev(), 0.1);
}