Class ComputationCostEstimator

    • Constructor Detail

      • ComputationCostEstimator

        public ComputationCostEstimator​(int scans,
                                        int decompressions,
                                        int overlappingDecompressions,
                                        int leftMultiplications,
                                        int rightMultiplications,
                                        int compressedMultiplication,
                                        int dictOps,
                                        boolean isDensifying)
    • Method Detail

      • getCost

        public double getCost​(int nRows,
                              int nRowsScanned,
                              int nCols,
                              int nVals,
                              double sparsity)
        Get the cost of a column group.
        Parameters:
        nRows - The total number of rows
        nRowsScanned - Number of rows to process in this specific group
        nCols - Number of columns in the column group
        nVals - Number of unique tuples contained in the group
        sparsity - The sparsity of the unique tuples stored
        Returns:
        A cost
      • isDense

        public boolean isDense()
      • getCost

        public double getCost​(MatrixBlock mb)
        Description copied from class: ACostEstimate
        Get the cost of a matrix block.
        Specified by:
        getCost in class ACostEstimate
        Parameters:
        mb - A MatrixBlock
        Returns:
        The cost subject to the internal cost functions
      • getCost

        public double getCost​(AColGroup cg,
                              int nRows)
        Description copied from class: ACostEstimate
        Get the cost of a compressed columnGroup.
        Specified by:
        getCost in class ACostEstimate
        Parameters:
        cg - A ColumnGroup
        nRows - The number of rows in the column group
        Returns:
        The cost subject to the internal cost functions
      • shouldSparsify

        public boolean shouldSparsify()
        Description copied from class: ACostEstimate
        Ask the cost estimator if it is a good idea to try to sparsify a column group. It is the same as asking if it is a good idea to make FOR on top of the column group.
        Specified by:
        shouldSparsify in class ACostEstimate
        Returns:
        true if yes