Class TupleUnion<S extends Summary>

java.lang.Object
org.apache.datasketches.tuple.TupleUnion<S>
Type Parameters:
S - Type of Summary
public class TupleUnion<S extends Summary> extends Object
Compute the union of two or more generic tuple sketches or generic TupleSketches combined with ThetaSketches. A new instance represents an empty set.

  • Constructor Details

    • TupleUnion

      public TupleUnion(SummarySetOperations<S> summarySetOps)
      Creates new TupleUnion instance with instructions on how to process two summaries that overlap. This will have the default nominal entries (K).
      Parameters:
      summarySetOps - instance of SummarySetOperations

    • TupleUnion

      public TupleUnion(int nomEntries, SummarySetOperations<S> summarySetOps)
      Creates new TupleUnion instance.
      Parameters:
      nomEntries - nominal entries (K). Forced to the nearest power of 2 greater than given value.
      summarySetOps - instance of SummarySetOperations

  • Method Details

    • union

      public CompactTupleSketch<S> union(TupleSketch<S> tupleSketchA, TupleSketch<S> tupleSketchB)
      Perform a stateless, pair-wise union operation between two tuple sketches. The returned sketch will be cut back to the smaller of the two k values if required.

      Nulls and empty sketches are ignored.

      Parameters:
      tupleSketchA - The first argument
      tupleSketchB - The second argument
      Returns:
      the result ordered CompactTupleSketch on the heap.

    • union

      public CompactTupleSketch<S> union(TupleSketch<S> tupleSketch, ThetaSketch thetaSketch, S summary)
      Perform a stateless, pair-wise union operation between a tupleSketch and a ThetaSketch. The returned sketch will be cut back to the smaller of the two k values if required.

      Nulls and empty sketches are ignored.

      Parameters:
      tupleSketch - The first argument
      thetaSketch - The second argument
      summary - the given proxy summary for the ThetaSketch, which doesn't have one. This may not be null.
      Returns:
      the result ordered CompactTupleSketch on the heap.

    • union

      public void union(TupleSketch<S> tupleSketch)
      Performs a stateful union of the internal set with the given TupleSketch.
      Parameters:
      tupleSketch - input tuple sketch to merge with the internal set. Nulls and empty sketches are ignored.

    • union

      public void union(ThetaSketch thetaSketch, S summary)
      Performs a stateful union of the internal set with the given ThetaSketch by combining entries using the hashes from the ThetaSketch and summary values from the given summary.
      Parameters:
      thetaSketch - the given ThetaSketch input. If null or empty, it is ignored.
      summary - the given proxy summary for the ThetaSketch, which doesn't have one. This may not be null.

    • getResult

      public CompactTupleSketch<S> getResult()
      Gets the result of a sequence of stateful union operations as an unordered CompactTupleSketch
      Returns:
      result of the stateful unions so far. The state of this operation is not reset after the result is returned.

    • getResult

      public CompactTupleSketch<S> getResult(boolean reset)
      Gets the result of a sequence of stateful union operations as an unordered CompactTupleSketch.
      Parameters:
      reset - If true, clears this operator to the empty state after this result is returned. Set this to false if you wish to obtain an intermediate result.
      Returns:
      result of the stateful union

    • reset

      public void reset()
      Resets the internal set to the initial state, which represents an empty set. This is only useful after sequences of stateful union operations.