Package org.apache.datasketches.quantilescommon

Class ItemsSketchSortedView<T>

java.lang.Object
org.apache.datasketches.quantilescommon.ItemsSketchSortedView<T>
Type Parameters:
T - The sketch data type
All Implemented Interfaces:
GenericSortedView<T>, PartitioningFeature<T>, SketchPartitionLimits, SortedView
public class ItemsSketchSortedView<T> extends Object implements GenericSortedView<T>
The SortedView for the KllItemsSketch and the classic ItemsSketch.
Author:
Alexander Saydakov, Lee Rhodes

  • Constructor Details

    • ItemsSketchSortedView

      public ItemsSketchSortedView(T[] quantiles, long[] cumWeights, QuantilesGenericAPI<T> sk)
      Constructor.
      Parameters:
      quantiles - the given array of quantiles, which must be ordered.
      cumWeights - the given array of cumulative weights, which must be ordered, start with the value one, and the last value must be equal to N, the total number of items updated to the sketch.
      sk - the underlying quantile sketch.

  • Method Details

    • getComparator

      public Comparator<? super T> getComparator()
      Description copied from interface: GenericSortedView
      Gets the Comparator for this generic type.
      Specified by:
      getComparator in interface GenericSortedView<T>
      Returns:
      the Comparator for this generic type.

    • getCumulativeWeights

      public long[] getCumulativeWeights()
      Description copied from interface: SortedView
      Returns the array of cumulative weights from the sketch. Also known as the natural ranks, which are the Natural Numbers on the interval [1, N].
      Specified by:
      getCumulativeWeights in interface SortedView
      Returns:
      the array of cumulative weights (or natural ranks).

    • getMaxItem

      public T getMaxItem()
      Description copied from interface: GenericSortedView
      Returns the maximum item of the stream. This may be distinct from the largest item retained by the sketch algorithm.
      Specified by:
      getMaxItem in interface GenericSortedView<T>
      Returns:
      the maximum item of the stream

    • getMinItem

      public T getMinItem()
      Description copied from interface: GenericSortedView
      Returns the minimum item of the stream. This may be distinct from the smallest item retained by the sketch algorithm.
      Specified by:
      getMinItem in interface GenericSortedView<T>
      Returns:
      the minimum item of the stream

    • getN

      public long getN()
      Description copied from interface: SketchPartitionLimits
      Gets the length of the input stream offered to the sketch..
      Specified by:
      getN in interface SketchPartitionLimits
      Specified by:
      getN in interface SortedView
      Returns:
      the length of the input stream offered to the sketch.

    • getNumRetained

      public int getNumRetained()
      Description copied from interface: SortedView
      Gets the number of quantiles retained by this sorted view. This may be slightly different from the function with the same name when called from the originating sketch.
      Specified by:
      getNumRetained in interface SortedView
      Returns:
      the number of quantiles retained by this sorted view

    • getMaxPartitions

      public int getMaxPartitions()
      Description copied from interface: SketchPartitionLimits
      Gets the maximum number of partitions this sketch will support based on the configured size K and the number of retained values of this sketch.
      Specified by:
      getMaxPartitions in interface SketchPartitionLimits
      Returns:
      the maximum number of partitions this sketch will support.

    • getPartitionBoundariesFromPartSize

      public GenericPartitionBoundaries<T> getPartitionBoundariesFromPartSize(long nominalPartitionSize, QuantileSearchCriteria searchCrit)
      Description copied from interface: PartitioningFeature
      This method returns an instance of GenericPartitionBoundaries which provides sufficient information for the user to create the given number of equally sized partitions, where "equally sized" refers to an approximately equal number of items per partition.

      The sketch must not be empty.

      Specified by:
      getPartitionBoundariesFromPartSize in interface PartitioningFeature<T>
      Parameters:
      nominalPartitionSize - an integer that specifies the nominal size, in items, of each target partition. This must be a positive integer greater than getMinPartitionSizeItems().
      searchCrit - If INCLUSIVE, all the returned quantiles are the upper boundaries of the equally sized partitions with the exception of the lowest returned quantile, which is the lowest boundary of the lowest ranked partition. If EXCLUSIVE, all the returned quantiles are the lower boundaries of the equally sized partitions with the exception of the highest returned quantile, which is the upper boundary of the highest ranked partition.
      Returns:
      an instance of GenericPartitionBoundaries.

    • getPartitionBoundariesFromNumParts

      public GenericPartitionBoundaries<T> getPartitionBoundariesFromNumParts(int numEquallySizedParts, QuantileSearchCriteria searchCrit)
      Description copied from interface: PartitioningFeature
      This method returns an instance of GenericPartitionBoundaries which provides sufficient information for the user to create the given number of equally sized partitions, where "equally sized" refers to an approximately equal number of items per partition.

      The sketch must not be empty.

      Specified by:
      getPartitionBoundariesFromNumParts in interface PartitioningFeature<T>
      Parameters:
      numEquallySizedParts - an integer that specifies the number of equally sized partitions between getMinItem() and getMaxItem(). This must be a positive integer less than getMaxPartitions()
      • A 1 will return: minItem, maxItem.
      • A 2 will return: minItem, median quantile, maxItem.
      • Etc.
      searchCrit - If INCLUSIVE, all the returned quantiles are the upper boundaries of the equally sized partitions with the exception of the lowest returned quantile, which is the lowest boundary of the lowest ranked partition. If EXCLUSIVE, all the returned quantiles are the lower boundaries of the equally sized partitions with the exception of the highest returned quantile, which is the upper boundary of the highest ranked partition.
      Returns:
      an instance of GenericPartitionBoundaries.

    • getQuantile

      public T getQuantile(double rank, QuantileSearchCriteria searchCrit)
      Description copied from interface: GenericSortedView
      Gets the approximate quantile of the given normalized rank and the given search criterion.
      Specified by:
      getQuantile in interface GenericSortedView<T>
      Parameters:
      rank - the given normalized rank, a double in the range [0.0, 1.0].
      searchCrit - If INCLUSIVE, the given rank includes all quantiles ≤ the quantile directly corresponding to the given rank. If EXCLUSIVE, he given rank includes all quantiles < the quantile directly corresponding to the given rank.
      Returns:
      the approximate quantile given the normalized rank.
      See Also:

    • getQuantiles

      public T[] getQuantiles(double[] ranks, QuantileSearchCriteria searchCrit)
      Gets an array of quantiles corresponding to the given array of ranks.
      Parameters:
      ranks - the given array of normalized ranks
      searchCrit - The search criterion: either INCLUSIVE or EXCLUSIVE.
      Returns:
      an array of quantiles corresponding to the given array of ranks.

    • getQuantiles

      public T[] getQuantiles()
      Description copied from interface: GenericSortedView
      Returns the full array of quantiles.
      Specified by:
      getQuantiles in interface GenericSortedView<T>
      Returns:
      the full array of quantiles.

    • getRank

      public double getRank(T quantile, QuantileSearchCriteria searchCrit)
      Description copied from interface: GenericSortedView
      Gets the normalized rank corresponding to the given a quantile.
      Specified by:
      getRank in interface GenericSortedView<T>
      Parameters:
      quantile - the given quantile
      searchCrit - if INCLUSIVE the given quantile is included into the rank.
      Returns:
      the normalized rank corresponding to the given quantile.
      See Also:

    • isEmpty

      public boolean isEmpty()
      Description copied from interface: SortedView
      Returns true if this sorted view is empty.
      Specified by:
      isEmpty in interface SortedView
      Returns:
      true if this sorted view is empty.

    • iterator

      public GenericSortedViewIterator<T> iterator()
      Description copied from interface: SortedView
      Returns an iterator for this Sorted View.
      Specified by:
      iterator in interface GenericSortedView<T>
      Specified by:
      iterator in interface SortedView
      Returns:
      an iterator for this Sorted View.