Class ArrayOfStringsSketch

Direct Known Subclasses:
FdtSketch

public class ArrayOfStringsSketch extends UpdatableSketch<String[],ArrayOfStringsSummary>
Author:
Lee Rhodes
  • Constructor Details

    • ArrayOfStringsSketch

      public ArrayOfStringsSketch()
      Constructs new sketch with default K = 4096 (lgK = 12), default ResizeFactor=X8, and default p = 1.0.
    • ArrayOfStringsSketch

      public ArrayOfStringsSketch(int lgK)
      Constructs new sketch with default ResizeFactor=X8, default p = 1.0 and given lgK.
      Parameters:
      lgK - Log_base2 of Nominal Entries. See Nominal Entries
    • ArrayOfStringsSketch

      public ArrayOfStringsSketch(int lgK, ResizeFactor rf, float p)
      Constructs new sketch with given ResizeFactor, p and lgK.
      Parameters:
      lgK - Log_base2 of Nominal Entries. See Nominal Entries
      rf - ResizeFactor See Resize Factor
      p - sampling probability See Sampling Probability
    • ArrayOfStringsSketch

      @Deprecated public ArrayOfStringsSketch(org.apache.datasketches.memory.Memory mem)
      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 ArrayOfStringsSketch, and usually with data.
      Parameters:
      mem - the given Memory
    • ArrayOfStringsSketch

      public ArrayOfStringsSketch(ArrayOfStringsSketch sketch)
      Copy Constructor
      Parameters:
      sketch - the sketch to copy
  • Method Details

    • copy

      public ArrayOfStringsSketch copy()
      Overrides:
      copy in class UpdatableSketch<String[],ArrayOfStringsSummary>
      Returns:
      a deep copy of this sketch
    • update

      public void update(String[] strArrKey, String[] strArr)
      Updates the sketch with String arrays for both key and value.
      Parameters:
      strArrKey - the given String array key
      strArr - the given String array 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

      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

      Description copied from class: Sketch
      Returns a SketchIterator
      Specified by:
      iterator in class Sketch<S extends Summary>
      Returns:
      a SketchIterator