org.apache.sysds.runtime.compress.colgroup

Class Dictionary

java.lang.Object

org.apache.sysds.runtime.compress.colgroup.ADictionary

org.apache.sysds.runtime.compress.colgroup.Dictionary

public class Dictionary
extends ADictionary

This dictionary class aims to encapsulate the storage and operations over unique floating point values of a column group. The primary reason for its introduction was to provide an entry point for specialization such as shared dictionaries, which require additional information.

Constructor Summary

Constructors

Constructor and Description
Dictionary(double[] values)

Method Summary

Modifier and Type	Method and Description
double	aggregate(double init, Builtin fn) Aggregate all the contained values, useful in value only computations where the operation is iterating through all values contained in the dictionary.
Dictionary	apply(ScalarOperator op) Applies the scalar operation on the dictionary.
Dictionary	applyScalarOp(ScalarOperator op, double newVal, int numCols) Applies the scalar operation on the dictionary.
Dictionary	clone() Returns a deep clone of the dictionary.
long	getExactSizeOnDisk() Calculate the space consumption if the dictionary is stored on disk.
long	getInMemorySize() Returns the memory usage of the dictionary.
int	getNumberOfValues(int ncol) Get the number of values given that the column group has n columns
double	getValue(int i) Get Specific value contained in the dictionary at index.
double[]	getValues() Get all the values contained in the dictionary as a linearized double array.
int	getValuesLength() returns the count of values contained in the dictionary.
int	hasZeroTuple(int ncol) Determines if the content has a zero tuple.
static Dictionary	read(DataInput in)
void	write(DataOutput out) Write the dictionary to a DataOutput.

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

aggregateCols, read

Methods inherited from class java.lang.Object

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

Constructor Detail

Dictionary

public Dictionary(double[] values)

Method Detail

getValues

public double[] getValues()

Description copied from class: ADictionary

Get all the values contained in the dictionary as a linearized double array.

Specified by:

getValues in class ADictionary

Returns:

linearized double array

getValue

public double getValue(int i)

Description copied from class: ADictionary

Get Specific value contained in the dictionary at index.

Specified by:

getValue in class ADictionary

Parameters:

i - The index to extract the value from

Returns:

The value contained at the index

getInMemorySize

public long getInMemorySize()

Description copied from class: ADictionary

Returns the memory usage of the dictionary.

Specified by:

getInMemorySize in class ADictionary

Returns:

a long value in number of bytes for the dictionary.

hasZeroTuple

public int hasZeroTuple(int ncol)

Description copied from class: ADictionary

Determines if the content has a zero tuple. meaning all values at a specific row are zero value. This is useful information to find out if the dictionary is used in a dense context. To improve some specific operations.

Specified by:

hasZeroTuple in class ADictionary

Parameters:

ncol - The number of columns in the dictionary.

Returns:

The index at which the zero tuple is located.

aggregate

public double aggregate(double init,
                        Builtin fn)

Description copied from class: ADictionary

Aggregate all the contained values, useful in value only computations where the operation is iterating through all values contained in the dictionary.

Specified by:

aggregate in class ADictionary

Parameters:

init - The initial Value, in cases such as Max value, this could be -infinity

fn - The Function to apply to values

Returns:

The aggregated value as a double.

apply

public Dictionary apply(ScalarOperator op)

Description copied from class: ADictionary

Applies the scalar operation on the dictionary. Note that this operation modifies the underlying data, and normally require a copy of the original Dictionary to preserve old objects.

Specified by:

apply in class ADictionary

Parameters:

op - The operator to apply to the dictionary values.

Returns:

this dictionary with modified values.

applyScalarOp

public Dictionary applyScalarOp(ScalarOperator op,
                                double newVal,
                                int numCols)

Description copied from class: ADictionary

Applies the scalar operation on the dictionary. The returned dictionary should contain a new instance of the underlying data. Therefore it will not modify the previous object.

Specified by:

applyScalarOp in class ADictionary

Parameters:

op - The operator to apply to the dictionary values.

newVal - The value to append to the dictionary.

numCols - The number of columns stored in the dictionary.

Returns:

Another dictionary with modified values.

clone

public Dictionary clone()

Description copied from class: ADictionary

Returns a deep clone of the dictionary.

Specified by:

clone in class ADictionary

getValuesLength

public int getValuesLength()

Description copied from class: ADictionary

returns the count of values contained in the dictionary.

Specified by:

getValuesLength in class ADictionary

Returns:

an integer of count of values.

read

public static Dictionary read(DataInput in)
                       throws IOException

Throws:

IOException

write

public void write(DataOutput out)
           throws IOException

Description copied from class: ADictionary

Write the dictionary to a DataOutput.

Specified by:

write in class ADictionary

Parameters:

out - the output sink to write the dictionary to.

Throws:

IOException - if the sink fails.

getExactSizeOnDisk

public long getExactSizeOnDisk()

Description copied from class: ADictionary

Calculate the space consumption if the dictionary is stored on disk.

Specified by:

getExactSizeOnDisk in class ADictionary

Returns:

the long count of bytes to store the dictionary.

getNumberOfValues

public int getNumberOfValues(int ncol)

Description copied from class: ADictionary

Get the number of values given that the column group has n columns

Specified by:

getNumberOfValues in class ADictionary

Parameters:

ncol - The number of Columns in the ColumnGroup.

Returns:

the number of value tuples contained in the dictionary.