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

Class AOffset

java.lang.Object

org.apache.sysds.runtime.compress.colgroup.offset.AOffset

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

OffsetByte, OffsetChar, OffsetEmpty, OffsetSingle, OffsetTwo

public abstract class AOffset
extends Object
implements Serializable

Offset list encoder interface. It is assumed that the input is in sorted order, all values are positive and there are no duplicates. The no duplicate is important since 0 values are exploited to encode an offset of max representable value + 1. This gives the ability to encode data, where the offsets are greater than the available highest value that can be represented size.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AOffset.OffsetSliceInfo

Constructor Summary

Constructors

Constructor	Description
AOffset()

Method Summary

Modifier and Type	Method	Description
AOffset	append(AOffset t, int s)	Append the offsets from that other offset to the offsets in this.
AOffset	appendN(AOffsetsGroup[] g, int s)	Append a list of offsets together in order.
void	cacheIterator(AIterator it, int row)	Cache a iterator in use, note that there is no check for if the iterator is correctly positioned at the given row
boolean	equals(AOffset b)
abstract long	getExactSizeOnDisk()	Remember to include the ordinal of the type of offset list.
abstract long	getInMemorySize()	Get the in memory size of the Offset object
abstract AIterator	getIterator()	Get an iterator of the offsets while also maintaining the data index pointer.
AIterator	getIterator(int row)	Get an iterator that is pointing at a specific offset.
abstract AOffsetIterator	getOffsetIterator()	Get an OffsetIterator of current offsets not maintaining the data index.
AOffsetIterator	getOffsetIterator(int row)	Get an iterator that is pointing only at offsets from specific offset
abstract int	getOffsetToFirst()	Get the offset to the first index
abstract int	getOffsetToLast()	Get the offset to the last value
abstract int	getSize()	Get the number of contained elements, This method iterate the entire offset list, so it is not constant lookup.
void	preAggregateDenseMap(MatrixBlock m, double[] preAV, int rl, int ru, int cl, int cu, int nVal, AMapToData data)
void	preAggregateSparseMap(SparseBlock sb, double[] preAV, int rl, int ru, int nVal, AMapToData data)
static AOffset	reverse(int numRows, AOffset offsets)
AOffset.OffsetSliceInfo	slice(int l, int u)
String	toString()
abstract void	write(DataOutput out)	Write the offsets to disk.

Methods inherited from class java.lang.Object

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

Constructor Detail

AOffset

public AOffset()

Method Detail

getIterator

public abstract AIterator getIterator()

Get an iterator of the offsets while also maintaining the data index pointer.

Returns:

AIterator that iterate through index and dictionary offset values.

getOffsetIterator

public abstract AOffsetIterator getOffsetIterator()

Get an OffsetIterator of current offsets not maintaining the data index.

Returns:

AIterator that iterator through the delta offsets.

getIterator

public AIterator getIterator(int row)

Get an iterator that is pointing at a specific offset.

Parameters:

row - The row requested.

Returns:

AIterator that iterate through index and dictionary offset values.

getOffsetIterator

public AOffsetIterator getOffsetIterator(int row)

Get an iterator that is pointing only at offsets from specific offset

Parameters:

row - The row requested.

Returns:

AOffsetIterator that iterate through index only offset values.

cacheIterator

public void cacheIterator(AIterator it,
                          int row)

Cache a iterator in use, note that there is no check for if the iterator is correctly positioned at the given row

Parameters:

it - The Iterator to cache

row - The row index to cache the iterator as.

write

public abstract void write(DataOutput out)
                    throws IOException

Write the offsets to disk. If you implement another remember to write the ordinal of the new type to disk as well and add it to the OffsetFactory.

Parameters:

out - The output to write to

Throws:

IOException - Exception that happens if the IO fails to write.

getOffsetToFirst

public abstract int getOffsetToFirst()

Get the offset to the first index

Returns:

The first index offset

getOffsetToLast

public abstract int getOffsetToLast()

Get the offset to the last value

Returns:

The last values offset

getInMemorySize

public abstract long getInMemorySize()

Get the in memory size of the Offset object

Returns:

In memory size as a long.

getExactSizeOnDisk

public abstract long getExactSizeOnDisk()

Remember to include the ordinal of the type of offset list.

Returns:

the size on disk as a long.

getSize

public abstract int getSize()

Get the number of contained elements, This method iterate the entire offset list, so it is not constant lookup.

Returns:

The number of indexes.

preAggregateDenseMap

public final void preAggregateDenseMap(MatrixBlock m,
                                       double[] preAV,
                                       int rl,
                                       int ru,
                                       int cl,
                                       int cu,
                                       int nVal,
                                       AMapToData data)

preAggregateSparseMap

public final void preAggregateSparseMap(SparseBlock sb,
                                        double[] preAV,
                                        int rl,
                                        int ru,
                                        int nVal,
                                        AMapToData data)

equals

public boolean equals(AOffset b)

slice

public AOffset.OffsetSliceInfo slice(int l,
                                     int u)

append

public AOffset append(AOffset t,
                      int s)

Append the offsets from that other offset to the offsets in this.

Parameters:

t - That offset/

s - The total length encoded in this offset.

Returns:

this offsets followed by thats offsets.

appendN

public AOffset appendN(AOffsetsGroup[] g,
                       int s)

Append a list of offsets together in order.

Parameters:

g - The offsets to append together (note fist entry is equal to this)

s - The standard size of each g (except last, but that does not matter)

Returns:

The combined offsets.

toString

public String toString()

Overrides:

toString in class Object

reverse

public static AOffset reverse(int numRows,
                              AOffset offsets)