public class ColGroupFactory extends Object
| Constructor and Description | 
|---|
| ColGroupFactory() | 
| Modifier and Type | Method and Description | 
|---|---|
| static List<ColGroup> | assignColumns(int numCols,
             ColGroup[] colGroups,
             MatrixBlock rawBlock,
             CompressionSettings compSettings)Method for producing the final ColGroupList stored inside the CompressedMatrixBlock. | 
| static ColGroup | compress(int[] colIndexes,
        int rlen,
        ABitmap ubm,
        ColGroup.CompressionType compType,
        CompressionSettings cs,
        MatrixBlock rawMatrixBlock)Method for compressing an ColGroup. | 
| static ColGroup[] | compressColGroups(MatrixBlock in,
                 HashMap<Integer,Double> compRatios,
                 List<int[]> groups,
                 CompressionSettings compSettings,
                 int k)The actual compression method, that handles the logic of compressing multiple columns together. | 
public static ColGroup[] compressColGroups(MatrixBlock in, HashMap<Integer,Double> compRatios, List<int[]> groups, CompressionSettings compSettings, int k)
in - The input matrix, that could have been transposed if CompSettings was set to do thatcompRatios - The previously computed Compression ratings of individual col indexes.groups - The column groups to consider compressing together.compSettings - The compression settings to construct the compression based on.k - The degree of parallelism used.public static ColGroup compress(int[] colIndexes, int rlen, ABitmap ubm, ColGroup.CompressionType compType, CompressionSettings cs, MatrixBlock rawMatrixBlock)
colIndexes - The Column indexes to compressrlen - The number of rows in the columnsubm - The Bitmap containing all the data needed for the compression (unless Uncompressed
                       ColGroup)compType - The CompressionType selectedcs - The compression Settings used for the given compressionrawMatrixBlock - The copy of the original input (maybe transposed) MatrixBlockpublic static List<ColGroup> assignColumns(int numCols, ColGroup[] colGroups, MatrixBlock rawBlock, CompressionSettings compSettings)
numCols - The number of columns in input matrixcolGroups - The colgroups made to assignrawBlock - The (maybe transposed) original MatrixBlockcompSettings - The Compressionsettings used.Copyright © 2020 The Apache Software Foundation. All rights reserved.