com.yahoo.tensor.functions

Class Reduce

java.lang.Object

com.yahoo.tensor.functions.TensorFunction

com.yahoo.tensor.functions.PrimitiveTensorFunction

com.yahoo.tensor.functions.Reduce

public class Reduce
extends PrimitiveTensorFunction

The reduce tensor operation returns a tensor produced from the argument tensor where some dimensions are collapsed to a single value using an aggregator function.

Author:

bratseth

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Reduce.Aggregator
private static class	Reduce.AvgAggregator
private static class	Reduce.CountAggregator
private static class	Reduce.MaxAggregator
private static class	Reduce.MinAggregator
private static class	Reduce.ProdAggregator
private static class	Reduce.SumAggregator
private static class	Reduce.ValueAggregator

Field Summary

Fields

Modifier and Type	Field and Description
private Reduce.Aggregator	aggregator
private TensorFunction	argument
private List<String>	dimensions

Constructor Summary

Constructors

Constructor and Description
Reduce(TensorFunction argument, Reduce.Aggregator aggregator) Creates a reduce function reducing aLL dimensions
Reduce(TensorFunction argument, Reduce.Aggregator aggregator, List<String> dimensions) Creates a reduce function.
Reduce(TensorFunction argument, Reduce.Aggregator aggregator, String dimension) Creates a reduce function reducing a single dimension

Method Summary

Modifier and Type	Method and Description
TensorFunction	argument()
List<TensorFunction>	arguments() Returns the function arguments of this node in the order they are applied
private String	commaSeparated(List<String> list)
<NAMETYPE extends TypeContext.Name> Tensor	evaluate(EvaluationContext<NAMETYPE> context) Evaluates this tensor.
static TensorType	outputType(TensorType inputType, List<String> reduceDimensions)
private Tensor	reduceAllGeneral(Tensor argument)
private TensorAddress	reduceDimensions(TensorAddress address, TensorType argumentType, TensorType reducedType)
private Tensor	reduceIndexedVector(IndexedTensor argument)
PrimitiveTensorFunction	toPrimitive() Translate this function - and all of its arguments recursively - to a tree of primitive functions only.
String	toString(ToStringContext context) Return a string representation of this context.
private TensorType	type(TensorType argumentType)
<NAMETYPE extends TypeContext.Name> TensorType	type(TypeContext<NAMETYPE> context) Returns the type of the tensor this produces given the input types in the context
TensorFunction	withArguments(List<TensorFunction> arguments) Returns a copy of this tensor function with the arguments replaced by the given list of arguments.

Methods inherited from class com.yahoo.tensor.functions.TensorFunction

evaluate, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

argument

private final TensorFunction argument

dimensions

private final List<String> dimensions

aggregator

private final Reduce.Aggregator aggregator

Constructor Detail

Reduce

public Reduce(TensorFunction argument,
              Reduce.Aggregator aggregator)

Creates a reduce function reducing aLL dimensions

Reduce

public Reduce(TensorFunction argument,
              Reduce.Aggregator aggregator,
              String dimension)

Creates a reduce function reducing a single dimension

Reduce

public Reduce(TensorFunction argument,
              Reduce.Aggregator aggregator,
              List<String> dimensions)

Creates a reduce function.

Parameters:

argument - the tensor to reduce

aggregator - the aggregator function to use

dimensions - the list of dimensions to remove. If an empty list is given, all dimensions are reduced, producing a dimensionless tensor (a scalar).

Throws:

IllegalArgumentException - if any of the tensor dimensions are not present in the input tensor

Method Detail

outputType

public static TensorType outputType(TensorType inputType,
                                    List<String> reduceDimensions)

argument

public TensorFunction argument()

arguments

public List<TensorFunction> arguments()

Description copied from class: TensorFunction

Returns the function arguments of this node in the order they are applied

Specified by:

arguments in class TensorFunction

withArguments

public TensorFunction withArguments(List<TensorFunction> arguments)

Description copied from class: TensorFunction

Returns a copy of this tensor function with the arguments replaced by the given list of arguments.

Specified by:

withArguments in class TensorFunction

toPrimitive

public PrimitiveTensorFunction toPrimitive()

Description copied from class: TensorFunction

Translate this function - and all of its arguments recursively - to a tree of primitive functions only.

Specified by:

toPrimitive in class TensorFunction

Returns:

a tree of primitive functions implementing this

toString

public String toString(ToStringContext context)

Description copied from class: TensorFunction

Return a string representation of this context.

Specified by:

toString in class TensorFunction

Parameters:

context - a context which must be passed to all nested functions when requesting the string value

commaSeparated

private String commaSeparated(List<String> list)

type

public <NAMETYPE extends TypeContext.Name> TensorType type(TypeContext<NAMETYPE> context)

Description copied from class: TensorFunction

Returns the type of the tensor this produces given the input types in the context

Specified by:

type in class TensorFunction

Parameters:

context - a context which must be passed to all nexted functions when evaluating

type

private TensorType type(TensorType argumentType)

evaluate

public <NAMETYPE extends TypeContext.Name> Tensor evaluate(EvaluationContext<NAMETYPE> context)

Description copied from class: TensorFunction

Evaluates this tensor.

Specified by:

evaluate in class TensorFunction

Parameters:

context - a context which must be passed to all nexted functions when evaluating

reduceDimensions

private TensorAddress reduceDimensions(TensorAddress address,
                                       TensorType argumentType,
                                       TensorType reducedType)

reduceAllGeneral

private Tensor reduceAllGeneral(Tensor argument)

reduceIndexedVector

private Tensor reduceIndexedVector(IndexedTensor argument)