org.apache.sysds.runtime.compress.colgroup

Class ColGroupCompressed

java.lang.Object

org.apache.sysds.runtime.compress.colgroup.AColGroup

org.apache.sysds.runtime.compress.colgroup.ColGroupCompressed

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

ColGroupConst, ColGroupEmpty, ColGroupValue

public abstract class ColGroupCompressed
extends AColGroup

Base class for column groups encoded Encoded in a compressed manner.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.sysds.runtime.compress.colgroup.AColGroup

AColGroup.CompressionType

Method Summary

Modifier and Type	Method and Description
void	computeColSums(double[] c, int nRows) Compute the column sum
double	getMax() Short hand method for getting maximum value contained in this column group.
double	getMin() Short hand method for getting minimum value contained in this column group.
abstract double[]	getValues() Get all the values in the colGroup.
abstract boolean	isLossy() Is Lossy
void	tsmm(MatrixBlock ret, int nRows) Do a transposed self matrix multiplication on the left side t(x) %*% x.
void	unaryAggregateOperations(AggregateUnaryOperator op, double[] c, int nRows, int rl, int ru) Unary Aggregate operator, since aggregate operators require new object output, the output becomes an uncompressed matrix.

Methods inherited from class org.apache.sysds.runtime.compress.colgroup.AColGroup

binaryRowOp, colSum, containsValue, copy, countNonZerosPerRow, decompressToBlock, decompressToBlock, estimateInMemorySize, get, getColIndices, getCompType, getExactSizeOnDisk, getNumberNonZeros, getNumCols, getNumValues, getValuesAsBlock, isDense, leftMultByAColGroup, leftMultByMatrix, leftMultByMatrix, readFields, replace, rightMultByMatrix, scalarOperation, shiftColIndices, sliceColumn, sliceColumns, toString, tsmmAColGroup, write

Methods inherited from class java.lang.Object

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

Method Detail

getValues

public abstract double[] getValues()

Description copied from class: AColGroup

Get all the values in the colGroup. Note that this is only the stored values not the way they are stored. Making the output a list of values used in that colGroup not the actual full column.

Specified by:

getValues in class AColGroup

Returns:

a double list of values.

isLossy

public abstract boolean isLossy()

Description copied from class: AColGroup

Is Lossy

Specified by:

isLossy in class AColGroup

Returns:

returns if the ColGroup is compressed in a lossy manner.

getMin

public double getMin()

Description copied from class: AColGroup

Short hand method for getting minimum value contained in this column group.

Specified by:

getMin in class AColGroup

Returns:

The minimum value contained in this ColumnGroup

getMax

public double getMax()

Description copied from class: AColGroup

Short hand method for getting maximum value contained in this column group.

Specified by:

getMax in class AColGroup

Returns:

The maximum value contained in this ColumnGroup

computeColSums

public void computeColSums(double[] c,
                           int nRows)

Description copied from class: AColGroup

Compute the column sum

Specified by:

computeColSums in class AColGroup

Parameters:

c - The array to add the column sum to.

nRows - The number of rows in the column group.

unaryAggregateOperations

public final void unaryAggregateOperations(AggregateUnaryOperator op,
                                           double[] c,
                                           int nRows,
                                           int rl,
                                           int ru)

Description copied from class: AColGroup

Unary Aggregate operator, since aggregate operators require new object output, the output becomes an uncompressed matrix.

Specified by:

unaryAggregateOperations in class AColGroup

Parameters:

op - The operator used

c - The output matrix block

nRows - The total number of rows in the Column Group

rl - The Starting Row to do aggregation from

ru - The last Row to do aggregation to (not included)

tsmm

public final void tsmm(MatrixBlock ret,
                       int nRows)

Description copied from class: AColGroup

Do a transposed self matrix multiplication on the left side t(x) %*% x. but only with this column group. This gives better performance since there is no need to iterate through all the rows of the matrix, but the execution can be limited to its number of distinct values. Note it only calculate the upper triangle

Specified by:

tsmm in class AColGroup

Parameters:

ret - The return matrix block [numColumns x numColumns]

nRows - The number of rows in the column group