Package org.apache.sysds.runtime.data

Class SparseRow

java.lang.Object
org.apache.sysds.runtime.data.SparseRow
All Implemented Interfaces:
Serializable
Direct Known Subclasses:
SparseRowScalar, SparseRowVector
public abstract class SparseRow extends Object implements Serializable
Base class for sparse row implementations such as sparse row vectors and sparse scalars (single value per row).
See Also:

  • Constructor Summary

    Constructors
    Constructor
    Description
    SparseRow()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    abstract boolean
    add(int col, double v)
    Add a value to a specified column with awareness of potential insertions.
    abstract SparseRow
    append(int col, double v)
    Appends a value to the end of the sparse row.
    abstract void
    compact()
    In-place compaction of non-zero-entries; removes zero entries and shifts non-zero entries to the left if necessary.
    abstract void
    compact(double eps)
    In-place compaction of values over eps away from zero; and shifts non-zero entries to the left if necessary.
    abstract SparseRow
    copy(boolean deep)
    Make a copy of this row.
    abstract double
    get(int col)
    Gets the value of a specified column.
    abstract int[]
    indexes()
    Get the index array of non-zero entries, co-aligned with the array of values.
    abstract boolean
    isEmpty()
    Indicates if the sparse row is empty, i.e., if is has size zero.
    abstract void
    reset(int estnns, int maxnns)
    Resets the sparse row to empty, after this call size and isEmpty are guaranteed to return 0 and true, respectively.
    abstract int
    searchIndexesFirstGT(int col)
     
    abstract int
    searchIndexesFirstGTE(int col)
    Get first index greater than equal column index.
    abstract boolean
    set(int col, double v)
    Sets the value of a specified column with awareness of potential overwrites or deletes (set to value zero).
    abstract int
    size()
    Get the number of non-zero values of the sparse row.
    abstract void
    sort()
    In-place sort of column-index value pairs in order to allow binary search after constant-time append was used for reading unordered sparse rows.
    String
    toString()
     
    abstract double[]
    values()
    Get the value array of non-zero entries, co-aligned with the array of indexes.

    Methods inherited from class java.lang.Object

    equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

  • Constructor Details

    • SparseRow

      public SparseRow()

  • Method Details

    • size

      public abstract int size()
      Get the number of non-zero values of the sparse row.
      Returns:
      number of non-zeros

    • isEmpty

      public abstract boolean isEmpty()
      Indicates if the sparse row is empty, i.e., if is has size zero.
      Returns:
      true if empty

    • values

      public abstract double[] values()
      Get the value array of non-zero entries, co-aligned with the array of indexes.
      Returns:
      array of values

    • indexes

      public abstract int[] indexes()
      Get the index array of non-zero entries, co-aligned with the array of values.
      Returns:
      array of indexes

    • reset

      public abstract void reset(int estnns, int maxnns)
      Resets the sparse row to empty, after this call size and isEmpty are guaranteed to return 0 and true, respectively.
      Parameters:
      estnns - estimated number of non-zeros
      maxnns - maximum number of non-zeros, e.g., number of columns

    • set

      public abstract boolean set(int col, double v)
      Sets the value of a specified column with awareness of potential overwrites or deletes (set to value zero).
      Parameters:
      col - column index, zero-based
      v - value
      Returns:
      true if the size of the sparse row changed

    • add

      public abstract boolean add(int col, double v)
      Add a value to a specified column with awareness of potential insertions.
      Parameters:
      col - column index, zero-based
      v - value
      Returns:
      true if the size of the sparse row changed

    • append

      public abstract SparseRow append(int col, double v)
      Appends a value to the end of the sparse row.
      Parameters:
      col - column index, zero-based
      v - value
      Returns:
      the row with an appended element

    • get

      public abstract double get(int col)
      Gets the value of a specified column. If the column index does not exist in the sparse row, this call returns zero.
      Parameters:
      col - column index, zero-based
      Returns:
      value

    • sort

      public abstract void sort()
      In-place sort of column-index value pairs in order to allow binary search after constant-time append was used for reading unordered sparse rows. We first check if already sorted and subsequently sort if necessary in order to get O(n) best case. Note: In-place sort is necessary in order to guarantee the memory estimate for operations that implicitly read that data set.

    • compact

      public abstract void compact()
      In-place compaction of non-zero-entries; removes zero entries and shifts non-zero entries to the left if necessary.

    • compact

      public abstract void compact(double eps)
      In-place compaction of values over eps away from zero; and shifts non-zero entries to the left if necessary.
      Parameters:
      eps - epsilon value

    • copy

      public abstract SparseRow copy(boolean deep)
      Make a copy of this row.
      Parameters:
      deep - if the copy should be deep
      Returns:
      A copy

    • searchIndexesFirstGTE

      public abstract int searchIndexesFirstGTE(int col)
      Get first index greater than equal column index.
      Parameters:
      col - column to be greater than
      Returns:
      index

    • searchIndexesFirstGT

      public abstract int searchIndexesFirstGT(int col)

    • toString

      public String toString()
      Overrides:
      toString in class Object