Package org.apache.sysds.runtime.compress.colgroup

Class ColGroupSDCSingleZeros

java.lang.Object

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

org.apache.sysds.runtime.compress.colgroup.AColGroupCompressed

org.apache.sysds.runtime.compress.colgroup.ADictBasedColGroup

org.apache.sysds.runtime.compress.colgroup.AColGroupValue

org.apache.sysds.runtime.compress.colgroup.APreAgg

org.apache.sysds.runtime.compress.colgroup.ASDCZero

org.apache.sysds.runtime.compress.colgroup.ColGroupSDCSingleZeros

All Implemented Interfaces:

Serializable, AOffsetsGroup

public class ColGroupSDCSingleZeros
extends ASDCZero

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 column group is handy in cases where sparse unsafe operations is executed on very sparse columns. Then the zeros would be materialized in the group without any overhead.

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	Description
AColGroup	append(AColGroup g)	Append the other column group to this column group.
AColGroup	appendNInternal(AColGroup[] g)
AColGroup	binaryRowOpLeft(BinaryOperator op, double[] v, boolean isRowSafe)	Perform a binary row operation.
AColGroup	binaryRowOpRight(BinaryOperator op, double[] v, boolean isRowSafe)	Perform a binary row operation.
boolean	containsValue(double pattern)	Detect if the column group contains a specific value.
static AColGroup	create(IColIndex colIndices, int numRows, ADictionary dict, AOffset offsets, int[] cachedCounts)
void	decompressToDenseBlockDenseDictionaryWithProvidedIterator(DenseBlock db, int rl, int ru, int offR, int offC, double[] values, AIterator it)
long	estimateInMemorySize()	Get the upper bound estimate of in memory allocation for the column group.
org.apache.sysds.runtime.compress.colgroup.AColGroup.ColGroupType	getColGroupType()
ICLAScheme	getCompressionScheme()	Get the compression scheme for this column group to enable compression of other data.
AColGroup.CompressionType	getCompType()	Obtain the compression type.
double	getCost(ComputationCostEstimator e, int nRows)	Get the computation cost associated with this column group.
int[]	getCounts(int[] counts)
long	getExactSizeOnDisk()	Returns the exact serialized size of column group.
double	getIdx(int r, int colIdx)	Get the value at a colGroup specific row/column index position.
int	getPreAggregateSize()
void	preAggregateDense(MatrixBlock m, double[] preAgg, int rl, int ru, int cl, int cu)	Pre aggregate a dense matrix block into a pre aggregate target (first step of left matrix multiplication)
void	preAggregateSparse(SparseBlock sb, double[] preAgg, int rl, int ru)
void	preAggregateThatDDCStructure(ColGroupDDC that, Dictionary ret)
void	preAggregateThatSDCSingleZerosStructure(ColGroupSDCSingleZeros that, Dictionary ret)
void	preAggregateThatSDCZerosStructure(ColGroupSDCZeros that, Dictionary ret)
static ColGroupSDCSingleZeros	read(DataInput in, int nRows)
AColGroup	replace(double pattern, double replace)	Make a copy of the column group values, and replace all values that match pattern with replacement value.
boolean	sameIndexStructure(AColGroupCompressed that)
AColGroup	scalarOperation(ScalarOperator op)	Perform the specified scalar operation directly on the compressed column group, without decompressing individual cells if possible.
AColGroup	sliceRows(int rl, int ru)	Slice range of rows out of the column group and return a new column group only containing the row segment.
String	toString()
AColGroup	unaryOperation(UnaryOperator op)	Perform unary operation on the column group and return a new column group
void	write(DataOutput out)

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

decompressToDenseBlock, decompressToDenseBlockDenseDictionary, getIterator, getNumRows, getOffsets, leftMultByMatrixNoPreAgg

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

leftMultByAColGroup, mmWithDictionary, preAggregate, preAggregateThatIndexStructure, tsmmAColGroup

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

centralMoment, computeColSums, getCounts, getNumberNonZeros, getNumValues, rexpandCols

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

decompressToDenseBlock, decompressToSparseBlock, getDictionary, rightMultByMatrix

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

getMax, getMin, getSum, isEmpty, preAggRows, tsmm, unaryAggregateOperations, unaryAggregateOperations

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

appendN, colSum, decompressToDenseBlock, decompressToSparseBlock, get, getColIndices, getNumCols, rightMultByMatrix, shiftColIndices, sliceColumn, sliceColumns

Methods inherited from class java.lang.Object

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

Method Detail

create

public static AColGroup create(IColIndex colIndices,
                               int numRows,
                               ADictionary dict,
                               AOffset offsets,
                               int[] cachedCounts)

getCompType

public AColGroup.CompressionType getCompType()

Description copied from class: AColGroup

Obtain the compression type.

Specified by:

getCompType in class AColGroup

Returns:

How the elements of the column group are compressed.

getColGroupType

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

decompressToDenseBlockDenseDictionaryWithProvidedIterator

public void decompressToDenseBlockDenseDictionaryWithProvidedIterator(DenseBlock db,
                                                                      int rl,
                                                                      int ru,
                                                                      int offR,
                                                                      int offC,
                                                                      double[] values,
                                                                      AIterator it)

Specified by:

decompressToDenseBlockDenseDictionaryWithProvidedIterator in class ASDCZero

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)

preAggregateSparse

public void preAggregateSparse(SparseBlock sb,
                               double[] preAgg,
                               int rl,
                               int ru)

Specified by:

preAggregateSparse in class APreAgg

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

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.

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, should be same length as dictionary length.

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, should be same length as dictionary length.

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.

write

public void write(DataOutput out)
           throws IOException

Overrides:

write in class ADictBasedColGroup

Throws:

IOException

read

public static ColGroupSDCSingleZeros read(DataInput in,
                                          int nRows)
                                   throws IOException

Throws:

IOException

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

sameIndexStructure

public boolean sameIndexStructure(AColGroupCompressed that)

preAggregateThatDDCStructure

public void preAggregateThatDDCStructure(ColGroupDDC that,
                                         Dictionary ret)

preAggregateThatSDCZerosStructure

public void preAggregateThatSDCZerosStructure(ColGroupSDCZeros that,
                                              Dictionary ret)

preAggregateThatSDCSingleZerosStructure

public void preAggregateThatSDCSingleZerosStructure(ColGroupSDCSingleZeros that,
                                                    Dictionary ret)

getPreAggregateSize

public int getPreAggregateSize()

Overrides:

getPreAggregateSize in class APreAgg

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

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)

getCompressionScheme

public ICLAScheme getCompressionScheme()

Description copied from class: AColGroup

Get the compression scheme for this column group to enable compression of other data.

Specified by:

getCompressionScheme in class AColGroup

Returns:

The compression scheme of this column group

toString

public String toString()

Overrides:

toString in class AColGroupValue