leventov commented on a change in pull request #6581: Moments Sketch custom aggregator URL: https://github.com/apache/incubator-druid/pull/6581#discussion_r247845408
########## File path: extensions-contrib/momentsketch/src/main/java/org/apache/druid/query/aggregation/momentsketch/MomentSketchWrapper.java ########## @@ -0,0 +1,169 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +package org.apache.druid.query.aggregation.momentsketch; + +import com.github.stanfordfuturedata.momentsketch.MomentSolver; +import com.github.stanfordfuturedata.momentsketch.MomentStruct; + +import java.nio.ByteBuffer; + +public class MomentSketchWrapper Review comment: This class contains mathematical bits that are not obvious. It's javadoc comment should refer to some document (a paper at least, but preferably something more approachable) after reading which a reader of this class could understand what is "moment solving", ArcSinh compression concept, what does `log(x + sqrt(1 + x^2))` mean, etc. Ideally it's just explained inline. P. S. I see those things are explained to some extent in `MomentSketchAggregatorFactory`. Please link to this class in the javadoc comment too. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
