Class ColGroupSDCZeros

  • All Implemented Interfaces:
    Serializable, AOffsetsGroup, IContainADictionary, IContainDefaultTuple, IMapToDataGroup

    public class ColGroupSDCZeros
    extends ASDCZero
    implements IMapToDataGroup
    Column group that sparsely encodes the dictionary values. The idea is that all values is encoded with indexes except the most common one. the most common one can be inferred by not being included in the indexes. If the values are very sparse then the most common one is zero. This is the case for this column group, that specifically exploits that the column contain lots of zero values. This column group is handy in cases where sparse unsafe operations is executed on very sparse columns.
    See Also:
    Serialized Form
    • Method Detail

      • getColGroupType

        public org.apache.sysds.runtime.compress.colgroup.AColGroup.ColGroupType getColGroupType()
      • getIdx

        public double getIdx​(int r,
                             int colIdx)
        Description copied from class: AColGroup
        Get the value at a colGroup specific row/column index position.
        Specified by:
        getIdx in class AColGroup
        Parameters:
        r - row
        colIdx - column index in the _colIndexes.
        Returns:
        value at the row/column index position
      • getCounts

        public int[] getCounts​(int[] counts)
      • preAggregateDense

        public void preAggregateDense​(MatrixBlock m,
                                      double[] preAgg,
                                      int rl,
                                      int ru,
                                      int cl,
                                      int cu)
        Description copied from class: APreAgg
        Pre aggregate a dense matrix block into a pre aggregate target (first step of left matrix multiplication)
        Specified by:
        preAggregateDense in class APreAgg
        Parameters:
        m - The matrix to preAggregate
        preAgg - The preAggregate target
        rl - Row lower on the left side matrix
        ru - Row upper on the left side matrix
        cl - Column lower on the left side matrix (or row lower in the column group)
        cu - Column upper on the left side matrix (or row upper in the column group)
      • estimateInMemorySize

        public long estimateInMemorySize()
        Description copied from class: AColGroup
        Get the upper bound estimate of in memory allocation for the column group.
        Overrides:
        estimateInMemorySize in class AColGroupValue
        Returns:
        an upper bound on the number of bytes used to store this ColGroup in memory.
      • scalarOperation

        public AColGroup scalarOperation​(ScalarOperator op)
        Description copied from class: AColGroup
        Perform the specified scalar operation directly on the compressed column group, without decompressing individual cells if possible.
        Specified by:
        scalarOperation in class AColGroup
        Parameters:
        op - operation to perform
        Returns:
        version of this column group with the operation applied
      • unaryOperation

        public AColGroup unaryOperation​(UnaryOperator op)
        Description copied from class: AColGroup
        Perform unary operation on the column group and return a new column group
        Specified by:
        unaryOperation in class AColGroup
        Parameters:
        op - The operation to perform
        Returns:
        The new column group
      • binaryRowOpLeft

        public AColGroup binaryRowOpLeft​(BinaryOperator op,
                                         double[] v,
                                         boolean isRowSafe)
        Description copied from class: AColGroup
        Perform a binary row operation.
        Specified by:
        binaryRowOpLeft in class AColGroup
        Parameters:
        op - The operation to execute
        v - The vector of values to apply the values contained should be at least the length of the highest value in the column index
        isRowSafe - True if the binary op is applied to an entire zero row and all results are zero
        Returns:
        A updated column group with the new values.
      • binaryRowOpRight

        public AColGroup binaryRowOpRight​(BinaryOperator op,
                                          double[] v,
                                          boolean isRowSafe)
        Description copied from class: AColGroup
        Perform a binary row operation.
        Specified by:
        binaryRowOpRight in class AColGroup
        Parameters:
        op - The operation to execute
        v - The vector of values to apply the values contained should be at least the length of the highest value in the column index
        isRowSafe - True if the binary op is applied to an entire zero row and all results are zero
        Returns:
        A updated column group with the new values.
      • getExactSizeOnDisk

        public long getExactSizeOnDisk()
        Description copied from class: AColGroup
        Returns the exact serialized size of column group. This can be used for example for buffer preallocation.
        Overrides:
        getExactSizeOnDisk in class ADictBasedColGroup
        Returns:
        exact serialized size for column group
      • preAggregateThatDDCStructure

        public void preAggregateThatDDCStructure​(ColGroupDDC that,
                                                 Dictionary ret)
      • replace

        public AColGroup replace​(double pattern,
                                 double replace)
        Description copied from class: AColGroup
        Make a copy of the column group values, and replace all values that match pattern with replacement value.
        Overrides:
        replace in class AColGroupValue
        Parameters:
        pattern - The value to look for
        replace - The value to replace the other value with
        Returns:
        A new Column Group, reusing the index structure but with new values.
      • getCost

        public double getCost​(ComputationCostEstimator e,
                              int nRows)
        Description copied from class: AColGroup
        Get the computation cost associated with this column group.
        Specified by:
        getCost in class AColGroup
        Parameters:
        e - The computation cost estimator
        nRows - the number of rows in the column group
        Returns:
        The cost of this column group
      • containsValue

        public boolean containsValue​(double pattern)
        Description copied from class: AColGroup
        Detect if the column group contains a specific value.
        Specified by:
        containsValue in class AColGroup
        Parameters:
        pattern - The value to look for.
        Returns:
        boolean saying true if the value is contained.
      • sliceRows

        public AColGroup sliceRows​(int rl,
                                   int ru)
        Description copied from class: AColGroup
        Slice range of rows out of the column group and return a new column group only containing the row segment. Note that this slice should maintain pointers back to the original dictionaries and only modify index structures.
        Specified by:
        sliceRows in class AColGroup
        Parameters:
        rl - The row to start at
        ru - The row to end at (not included)
        Returns:
        A new column group containing the specified row range.
      • append

        public AColGroup append​(AColGroup g)
        Description copied from class: AColGroup
        Append the other column group to this column group. This method tries to combine them to return a new column group containing both. In some cases it is possible in reasonable time, in others it is not. The result is first this column group followed by the other column group in higher row values. If it is not possible or very inefficient null is returned.
        Specified by:
        append in class AColGroup
        Parameters:
        g - The other column group
        Returns:
        A combined column group or null
      • appendNInternal

        public AColGroup appendNInternal​(AColGroup[] g,
                                         int blen,
                                         int rlen)
      • recompress

        public AColGroup recompress()
        Description copied from class: AColGroup
        Recompress this column group into a new column group.
        Specified by:
        recompress in class AColGroup
        Returns:
        A new or the same column group depending on optimization goal.
      • getEncoding

        public IEncode getEncoding()
        Description copied from class: AColGroup
        Get encoding of this column group.
        Overrides:
        getEncoding in class AColGroup
        Returns:
        The encoding of the index structure.