Class ThetaIntersection

java.lang.Object
org.apache.datasketches.theta.ThetaSetOperation
org.apache.datasketches.theta.ThetaIntersection
All Implemented Interfaces:
MemorySegmentStatus
public abstract class ThetaIntersection extends ThetaSetOperation
The API for intersection operations
Author:
Lee Rhodes

  • Constructor Details

    • ThetaIntersection

      public ThetaIntersection()
      No argument constructor.

  • Method Details

    • getFamily

      public Family getFamily()
      Description copied from class: ThetaSetOperation
      Gets the Family of this ThetaSetOperation
      Specified by:
      getFamily in class ThetaSetOperation
      Returns:
      the Family of this ThetaSetOperation

    • getResult

      public CompactThetaSketch getResult()
      Gets the result of this operation as an ordered CompactThetaSketch on the Java heap. This does not disturb the underlying data structure of this intersection. The intersect(ThetaSketch) method must have been called at least once, otherwise an exception will be thrown. This is because a virgin intersection represents the Universal Set, which has an infinite number of values.
      Returns:
      the result of this operation as an ordered CompactThetaSketch on the Java heap

    • getResult

      public abstract CompactThetaSketch getResult(boolean dstOrdered, MemorySegment dstSeg)
      Gets the result of this operation as a CompactThetaSketch in the given dstSeg. This does not disturb the underlying data structure of this intersection. The intersect(ThetaSketch) method must have been called at least once, otherwise an exception will be thrown. This is because a virgin intersection represents the Universal Set, which has an infinite number of values.

      Note that presenting an intersection with an empty sketch sets the internal state of the intersection to empty = true, and current count = 0. This is consistent with the mathematical definition of the intersection of any set with the empty set is always empty.

      Presenting an intersection with a null argument will throw an exception.

      Parameters:
      dstOrdered - See Destination Ordered
      dstSeg - the destination MemorySegment.
      Returns:
      the result of this operation as a CompactThetaSketch stored in the given dstSeg, which can be either on or off-heap..

    • hasResult

      public abstract boolean hasResult()
      Returns true if there is a valid intersection result available
      Returns:
      true if there is a valid intersection result available

    • reset

      public abstract void reset()
      Resets this ThetaIntersection for stateful operations only. The seed remains intact, otherwise reverts to the Universal Set: theta = 1.0, no retained data and empty = false.

    • toByteArray

      public abstract byte[] toByteArray()
      Serialize this intersection to a byte array form.
      Returns:
      byte array of this intersection

    • intersect

      public abstract void intersect(ThetaSketch sketchIn)
      Intersect the given sketch with the internal state. This method can be repeatedly called. If the given sketch is null the internal state becomes the empty sketch. Theta will become the minimum of thetas seen so far.
      Parameters:
      sketchIn - the given sketch

    • intersect

      public CompactThetaSketch intersect(ThetaSketch a, ThetaSketch b)
      Perform intersect set operation on the two given sketch arguments and return the result as an ordered CompactThetaSketch on the heap.
      Parameters:
      a - The first sketch argument
      b - The second sketch argument
      Returns:
      an ordered CompactThetaSketch on the heap

    • intersect

      public abstract CompactThetaSketch intersect(ThetaSketch a, ThetaSketch b, boolean dstOrdered, MemorySegment dstSeg)
      Perform intersect set operation on the two given sketches and return the result as a CompactThetaSketch.
      Parameters:
      a - The first sketch argument
      b - The second sketch argument
      dstOrdered - See Destination Ordered.
      dstSeg - the destination MemorySegment.
      Returns:
      the result as a CompactThetaSketch.

    • wrap

      public static ThetaIntersection wrap(MemorySegment srcSeg)
      Factory: Wrap a ThetaIntersection target around the given source MemorySegment containing intersection data. This method assumes the Default Update Seed. If the given source MemorySegment is read-only, the returned object will also be read-only.
      Parameters:
      srcSeg - The source MemorySegment image.
      Returns:
      a ThetaIntersection that wraps a source MemorySegment that contains a ThetaIntersection image

    • wrap

      public static ThetaIntersection wrap(MemorySegment srcSeg, long expectedSeed)
      Factory: Wrap a ThetaIntersection target around the given source MemorySegment containing intersection data. If the given source MemorySegment is read-only, the returned object will also be read-only.
      Parameters:
      srcSeg - The source MemorySegment image.
      expectedSeed - See seed
      Returns:
      a ThetaIntersection that wraps a source MemorySegment that contains a ThetaIntersection image