org.apache.sysds.runtime.compress.colgroup

Class ColGroupFactory

java.lang.Object

org.apache.sysds.runtime.compress.colgroup.ColGroupFactory

public final class ColGroupFactory
extends Object

Factory pattern for constructing ColGroups.

Constructor Summary

Constructors

Constructor and Description
ColGroupFactory()

Method Summary

Modifier and Type	Method and Description
static AColGroup	compress(int[] colIndexes, int rlen, ABitmap ubm, AColGroup.CompressionType compType, CompressionSettings cs, MatrixBlock rawMatrixBlock, double tupleSparsity) Method for compressing an ColGroup.
static List<AColGroup>	compressColGroups(MatrixBlock in, CompressedSizeInfo csi, CompressionSettings compSettings, int k) The actual compression method, that handles the logic of compressing multiple columns together.
static AColGroup	genColGroupConst(int numRows, int numCols, double value)
static AColGroup	getColGroupConst(int numRows, int[] cols, double value)

Methods inherited from class java.lang.Object

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

Constructor Detail

ColGroupFactory

public ColGroupFactory()

Method Detail

compressColGroups

public static List<AColGroup> compressColGroups(MatrixBlock in,
                                                CompressedSizeInfo csi,
                                                CompressionSettings compSettings,
                                                int k)

The actual compression method, that handles the logic of compressing multiple columns together. This method also have the responsibility of correcting any estimation errors previously made.

Parameters:

in - The input matrix, that could have been transposed if CompSettings was set to do that

csi - The compression Information extracted from the estimation, this contains which groups of columns to compress together

compSettings - The compression settings to construct the compression based on.

k - The degree of parallelism used.

Returns:

A Resulting array of ColGroups, containing the compressed information from the input matrix block.

compress

public static AColGroup compress(int[] colIndexes,
                                 int rlen,
                                 ABitmap ubm,
                                 AColGroup.CompressionType compType,
                                 CompressionSettings cs,
                                 MatrixBlock rawMatrixBlock,
                                 double tupleSparsity)

Method for compressing an ColGroup.

Parameters:

colIndexes - The Column indexes to compress

rlen - The number of rows in the columns

ubm - The Bitmap containing all the data needed for the compression (unless Uncompressed ColGroup)

compType - The CompressionType selected

cs - The compression Settings used for the given compression

rawMatrixBlock - The copy of the original input (maybe transposed) MatrixBlock

tupleSparsity - The sparsity of the ubs entries.

Returns:

A Compressed ColGroup

genColGroupConst

public static AColGroup genColGroupConst(int numRows,
                                         int numCols,
                                         double value)

getColGroupConst

public static AColGroup getColGroupConst(int numRows,
                                         int[] cols,
                                         double value)