presto-main/src/main/java/io/prestosql/operator/aggregation/GeometricMeanAggregations.java/GeometricMeanAggregations/output
class GeometricMeanAggregations:    @OutputFunction(StandardTypes.DOUBLE)
    public static void output(@AggregationState LongAndDoubleState state, BlockBuilder out)
    {
        long count = state.getLong();
        if (count == 0) {
            out.appendNull();
        }
        else {
            DOUBLE.writeDouble(out, Math.exp(state.getDouble() / count));
        }
    }