README.md

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# ILTS
- The code for ILTS and other baselines compared in query efficiency experiments are available in this repository.
    - ILTS is implemented in [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_ILTS.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_ILTS.java) with convex hull precomputation in [tsfile/src/main/java/org/apache/iotdb/tsfile/file/metadata/statistics/Statistics.java](tsfile/src/main/java/org/apache/iotdb/tsfile/file/metadata/statistics/Statistics.java).
    - LTTB is implemented in [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_LTTB.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_LTTB.java).
    - MinMaxLTTB is implemented in [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_MinMaxPreselection.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_MinMaxPreselection.java) and [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/GroupByWithoutValueFilterDataSet.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/GroupByWithoutValueFilterDataSet.java).
    - MinMax is implemented in [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_MinMax.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_MinMax.java).
    - M4 is implemented in [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_M4.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_M4.java).
    - OM3 is implemented by storing the OM3 coefficient table as regular time series and querying them with a `WHERE timestamp in (%s)` clause.
- The README of [Apache IoTDB](https://iotdb.apache.org/) itself is in [README_IOTDB.md](README_IOTDB.md). To build this repository, run `mvn clean package -DskipTests -pl -distribution`.
- Others:
    - Visval is implemented in [server/src/main/java/org/apache/iotdb/db/query/simpiece/Visval.java](server/src/main/java/org/apache/iotdb/db/query/simpiece/Visval.java).
    - Uniform is implemented in [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_Uniform.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_Uniform.java).
    - FSW is implemented in [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_FSW.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_FSW.java) and [server/src/main/java/org/apache/iotdb/db/query/simpiece/FSW.java](server/src/main/java/org/apache/iotdb/db/query/simpiece/FSW.java).
    - Sim-Piece is implemented in [server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_SimPiece.java](server/src/main/java/org/apache/iotdb/db/query/dataset/groupby/LocalGroupByExecutorTri_SimPiece.java) and [server/src/main/java/org/apache/iotdb/db/query/simpiece/SimPiece.java](server/src/main/java/org/apache/iotdb/db/query/simpiece/SimPiece.java).
    - Some integration tests for correctness are in [server/src/test/java/org/apache/iotdb/db/integration/tri/MyTest_ILTS.java](server/src/test/java/org/apache/iotdb/db/integration/tri/MyTest_ILTS.java).