org.apache.sysds.runtime.compress.colgroup

Class ColGroupOffset

java.lang.Object

org.apache.sysds.runtime.compress.colgroup.ColGroup

org.apache.sysds.runtime.compress.colgroup.ColGroupValue

org.apache.sysds.runtime.compress.colgroup.ColGroupOffset

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

ColGroupOLE, ColGroupRLE

public abstract class ColGroupOffset
extends ColGroupValue

Base class for column groups encoded with various types of bitmap encoding. NOTES: * OLE: separate storage segment length and bitmaps led to a 30% improvement but not applied because more difficult to support both data layouts at the same time (distributed/local as well as w/ and w/o low-level opt)

See Also:

Serialized Form

Nested Class Summary

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

ColGroup.CompressionType

Method Summary

Modifier and Type	Method and Description
void	decompressToBlock(MatrixBlock target, int colpos) Decompress to block.
void	decompressToBlock(MatrixBlock target, int[] colIndexTargets) Decompress the contents of this column group into uncompressed packed columns
void	decompressToBlock(MatrixBlock target, int rl, int ru) Decompress the contents of this column group into the specified full matrix block.
long	estimateInMemorySize() Note: Must be overridden by child classes to account for additional data and metadata
double	get(int r, int c) Get the value at a global row/column position.
int[]	getBitmapOffsets()
char[]	getBitmaps()
long	getExactSizeOnDisk() Returns the exact serialized size of column group.
abstract Iterator<Integer>	getIterator(int k)
Iterator<IJV>	getIterator(int rl, int ru, boolean inclZeros, boolean rowMajor) Create a column group iterator for a row index range.
abstract Iterator<Integer>	getIterator(int k, int rl, int ru)
boolean	hasZeros()
void	readFields(DataInput in) Deserialize column group from data input.
String	toString()
void	write(DataOutput out) Serializes column group to data output.

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

cleanupThreadLocalMemory, getByteValues, getCounts, getCounts, getCounts, getCounts, getIfCountsType, getNumValues, getValues, getValuesAsBlock, isLossy, setupThreadLocalMemory, unaryAggregateOperations, unaryAggregateOperations

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

countNonZerosPerRow, getColIndex, getColIndices, getCompType, getNumCols, getNumRows, getRowIterator, leftMultByMatrix, leftMultByRowVector, leftMultByRowVector, rightMultByMatrix, rightMultByVector, scalarOperation, shiftColIndices

Methods inherited from class java.lang.Object

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

Method Detail

estimateInMemorySize

public long estimateInMemorySize()

Description copied from class: ColGroup

Note: Must be overridden by child classes to account for additional data and metadata

Specified by:

estimateInMemorySize in class ColGroup

Returns:

an upper bound on the number of bytes used to store this ColGroup in memory.

decompressToBlock

public void decompressToBlock(MatrixBlock target,
                              int rl,
                              int ru)

Description copied from class: ColGroup

Decompress the contents of this column group into the specified full matrix block.

Specified by:

decompressToBlock in class ColGroup

Parameters:

target - a matrix block where the columns covered by this column group have not yet been filled in.

rl - row lower

ru - row upper

decompressToBlock

public void decompressToBlock(MatrixBlock target,
                              int[] colIndexTargets)

Description copied from class: ColGroup

Decompress the contents of this column group into uncompressed packed columns

Specified by:

decompressToBlock in class ColGroup

Parameters:

target - a dense matrix block. The block must have enough space to hold the contents of this column group.

colIndexTargets - array that maps column indices in the original matrix block to columns of target.

decompressToBlock

public void decompressToBlock(MatrixBlock target,
                              int colpos)

Description copied from class: ColGroup

Decompress to block.

Specified by:

decompressToBlock in class ColGroup

Parameters:

target - dense output vector

colpos - column to decompress, error if larger or equal numCols

get

public double get(int r,
                  int c)

Description copied from class: ColGroup

Get the value at a global row/column position.

Specified by:

get in class ColGroup

Parameters:

r - row

c - column

Returns:

value at the row/column position

getBitmaps

public char[] getBitmaps()

getBitmapOffsets

public int[] getBitmapOffsets()

hasZeros

public boolean hasZeros()

readFields

public void readFields(DataInput in)
                throws IOException

Description copied from class: ColGroup

Deserialize column group from data input.

Overrides:

readFields in class ColGroupValue

Parameters:

in - data input

Throws:

IOException - if IOException occurs

write

public void write(DataOutput out)
           throws IOException

Description copied from class: ColGroup

Serializes column group to data output.

Overrides:

write in class ColGroupValue

Parameters:

out - data output

Throws:

IOException - if IOException occurs

getExactSizeOnDisk

public long getExactSizeOnDisk()

Description copied from class: ColGroup

Returns the exact serialized size of column group. This can be used for example for buffer preallocation.

Overrides:

getExactSizeOnDisk in class ColGroupValue

Returns:

exact serialized size for column group

getIterator

public Iterator<IJV> getIterator(int rl,
                                 int ru,
                                 boolean inclZeros,
                                 boolean rowMajor)

Description copied from class: ColGroup

Create a column group iterator for a row index range.

Specified by:

getIterator in class ColGroup

Parameters:

rl - row lower index, inclusive

ru - row upper index, exclusive

inclZeros - include zero values into scope of iterator

rowMajor - use a row major iteration order

Returns:

an iterator instance

getIterator

public abstract Iterator<Integer> getIterator(int k)

Parameters:

k - index of value tuple with associated bitmap

Returns:

an iterator over the row offsets in this bitmap

getIterator

public abstract Iterator<Integer> getIterator(int k,
                                              int rl,
                                              int ru)

Parameters:

k - index of value tuple with associated bitmap

rl - row lower index, inclusive

ru - row upper index, exclusive

Returns:

an iterator over the row offsets in this bitmap

toString

public String toString()

Overrides:

toString in class ColGroupValue