in core/src/main/java/org/apache/commons/functor/aggregator/functions/DoublePercentileAggregatorFunction.java [117:128]
public Double evaluate(List<Double> data) {
if (data == null || data.size() == 0) {
return null;
}
List<Double> copy = data;
if (useCopy) {
copy = new ArrayList<Double>(data);
}
Collections.sort(copy);
int rank = computeRank(data);
return copy.get(rank);
}