Class SparseRow

    • Constructor Summary

      Constructors 
      Constructor Description
      SparseRow()  
    • Method Summary

      All Methods Instance Methods Abstract Methods Concrete Methods 
      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 void 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 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 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.
    • Constructor Detail

      • SparseRow

        public SparseRow()
    • Method Detail

      • 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 void append​(int col,
                                    double v)
        Appends a value to the end of the sparse row.
        Parameters:
        col - column index, zero-based
        v - value
      • 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