Package org.apache.datasketches.tuple.adouble

Class DoubleSketch

java.lang.Object
org.apache.datasketches.tuple.Sketch<S>
org.apache.datasketches.tuple.UpdatableSketch<Double,DoubleSummary>
org.apache.datasketches.tuple.adouble.DoubleSketch
public class DoubleSketch extends UpdatableSketch<Double,DoubleSummary>
Author:
Lee Rhodes

  • Constructor Details

    • DoubleSketch

      public DoubleSketch(int lgK, DoubleSummary.Mode mode)
      Constructs this sketch with given lgK.
      Parameters:
      lgK - Log_base2 of Nominal Entries. See Nominal Entries
      mode - The DoubleSummary mode to be used

    • DoubleSketch

      public DoubleSketch(int lgK, int lgResizeFactor, float samplingProbability, DoubleSummary.Mode mode)
      Creates this sketch with the following parameters:
      Parameters:
      lgK - Log_base2 of Nominal Entries.
      lgResizeFactor - log2(resizeFactor) - value from 0 to 3: 
       0 - no resizing (max size allocated),
 1 - double internal hash table each time it reaches a threshold
 2 - grow four times
 3 - grow eight times (default)
      samplingProbability - See Sampling Probability
      mode - The DoubleSummary mode to be used

    • DoubleSketch

      @Deprecated public DoubleSketch(org.apache.datasketches.memory.Memory mem, DoubleSummary.Mode mode)
      Deprecated.
      As of 3.0.0, heapifying an UpdatableSketch is deprecated. This capability will be removed in a future release. Heapifying a CompactSketch is not deprecated.
      Constructs this sketch from a Memory image, which must be from an DoubleSketch, and usually with data.
      Parameters:
      mem - the given Memory
      mode - The DoubleSummary mode to be used

  • Method Details

    • update

      public void update(String key, Double value)
      Description copied from class: UpdatableSketch
      Updates this sketch with a String key and U value. The value is passed to update() method of the Summary object associated with the key
      Overrides:
      update in class UpdatableSketch<Double,DoubleSummary>
      Parameters:
      key - The given String key
      value - The given U value

    • update

      public void update(long key, Double value)
      Description copied from class: UpdatableSketch
      Updates this sketch with a long key and U value. The value is passed to update() method of the Summary object associated with the key
      Overrides:
      update in class UpdatableSketch<Double,DoubleSummary>
      Parameters:
      key - The given long key
      value - The given U value

    • getRetainedEntries

      public int getRetainedEntries()
      Specified by:
      getRetainedEntries in class Sketch<S extends Summary>
      Returns:
      number of retained entries

    • getCountLessThanThetaLong

      public int getCountLessThanThetaLong(long thetaLong)
      Description copied from class: Sketch
      Gets the number of hash values less than the given theta expressed as a long.
      Specified by:
      getCountLessThanThetaLong in class Sketch<S extends Summary>
      Parameters:
      thetaLong - the given theta as a long between zero and Long.MAX_VALUE.
      Returns:
      the number of hash values less than the given thetaLong.

    • getNominalEntries

      public int getNominalEntries()
      Get configured nominal number of entries
      Returns:
      nominal number of entries

    • getLgK

      public int getLgK()
      Get log_base2 of Nominal Entries
      Returns:
      log_base2 of Nominal Entries

    • getSamplingProbability

      public float getSamplingProbability()
      Get configured sampling probability
      Returns:
      sampling probability

    • getCurrentCapacity

      public int getCurrentCapacity()
      Get current capacity
      Returns:
      current capacity

    • getResizeFactor

      public ResizeFactor getResizeFactor()
      Get configured resize factor
      Returns:
      resize factor

    • trim

      public void trim()
      Rebuilds reducing the actual number of entries to the nominal number of entries if needed

    • reset

      public void reset()
      Resets this sketch an empty state.

    • compact

      public CompactSketch<DoubleSummary> compact()
      Converts the current state of the sketch into a compact sketch
      Specified by:
      compact in class Sketch<S extends Summary>
      Returns:
      compact sketch

    • toByteArray

      @Deprecated public byte[] toByteArray()
      Deprecated.
      As of 3.0.0, serializing an UpdatableSketch is deprecated. This capability will be removed in a future release. Serializing a CompactSketch is not deprecated.
      This serializes an UpdatableSketch (QuickSelectSketch).
      Specified by:
      toByteArray in class Sketch<S extends Summary>
      Returns:
      serialized representation of an UpdatableSketch (QuickSelectSketch).

    • iterator

      public TupleSketchIterator<DoubleSummary> iterator()
      Description copied from class: Sketch
      Returns a SketchIterator
      Specified by:
      iterator in class Sketch<S extends Summary>
      Returns:
      a SketchIterator