Package ai.djl.training.dataset

Class RandomAccessDataset

java.lang.Object

ai.djl.training.dataset.RandomAccessDataset

All Implemented Interfaces:

Dataset

Direct Known Subclasses:

ArrayDataset

public abstract class RandomAccessDataset
extends java.lang.Object
implements Dataset

RandomAccessDataset represent the dataset that support random access reads. i.e. it could access a specific data item given the index.

Almost all datasets in DJL extend, either directly or indirectly, RandomAccessDataset.

See Also:

The guide to implementing a custom dataset

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	RandomAccessDataset.BaseBuilder<T extends RandomAccessDataset.BaseBuilder<T>>	The Builder to construct a RandomAccessDataset.

Nested classes/interfaces inherited from interface ai.djl.training.dataset.Dataset

Dataset.Usage

Field Summary

Fields

Modifier and Type	Field	Description
protected Batchifier	dataBatchifier
protected Device	device
protected Batchifier	labelBatchifier
protected long	limit
protected Pipeline	pipeline
protected int	prefetchNumber
protected Sampler	sampler
protected Pipeline	targetPipeline

Constructor Summary

Constructors

Constructor	Description
RandomAccessDataset(RandomAccessDataset.BaseBuilder<?> builder)	Creates a new instance of RandomAccessDataset with the given necessary configurations.

Method Summary

Modifier and Type	Method	Description
protected abstract long	availableSize()	Returns the number of records available to be read in this Dataset.
abstract Record	get(NDManager manager, long index)	Gets the Record for the given index from the dataset.
java.lang.Iterable<Batch>	getData(NDManager manager)	Fetches an iterator that can iterate through the Dataset.
java.lang.Iterable<Batch>	getData(NDManager manager, Sampler sampler)	Fetches an iterator that can iterate through the Dataset with a custom sampler.
java.lang.Iterable<Batch>	getData(NDManager manager, Sampler sampler, java.util.concurrent.ExecutorService executorService)	Fetches an iterator that can iterate through the Dataset with a custom sampler multi-threaded.
java.lang.Iterable<Batch>	getData(NDManager manager, java.util.concurrent.ExecutorService executorService)	Fetches an iterator that can iterate through the Dataset with multiple threads.
RandomAccessDataset[]	randomSplit(int... ratio)	Splits the dataset set into multiple portions.
long	size()	Returns the size of this Dataset.
RandomAccessDataset	subDataset(int fromIndex, int toIndex)	Returns a view of the portion of this data between the specified fromIndex, inclusive, and toIndex, exclusive.
ai.djl.util.Pair<java.lang.Number[][],java.lang.Number[][]>	toArray()	Returns the dataset contents as a Java array.

Methods inherited from class java.lang.Object

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

Methods inherited from interface ai.djl.training.dataset.Dataset

prepare, prepare

Field Detail

sampler

protected Sampler sampler

dataBatchifier

protected Batchifier dataBatchifier

labelBatchifier

protected Batchifier labelBatchifier

pipeline

protected Pipeline pipeline

targetPipeline

protected Pipeline targetPipeline

prefetchNumber

protected int prefetchNumber

limit

protected long limit

device

protected Device device

Constructor Detail

RandomAccessDataset

public RandomAccessDataset(RandomAccessDataset.BaseBuilder<?> builder)

Creates a new instance of RandomAccessDataset with the given necessary configurations.

Parameters:

builder - a builder with the necessary configurations

Method Detail

get

public abstract Record get(NDManager manager,
                           long index)
                    throws java.io.IOException

Gets the Record for the given index from the dataset.

Parameters:

manager - the manager used to create the arrays

index - the index of the requested data item

Returns:

a Record that contains the data and label of the requested data item

Throws:

java.io.IOException - if an I/O error occurs

getData

public java.lang.Iterable<Batch> getData(NDManager manager)
                                  throws java.io.IOException,
                                         TranslateException

Fetches an iterator that can iterate through the Dataset.

Specified by:

getData in interface Dataset

Parameters:

manager - the dataset to iterate through

Returns:

an Iterable of Batch that contains batches of data from the dataset

Throws:

java.io.IOException - for various exceptions depending on the dataset

TranslateException - if there is an error while processing input

getData

public java.lang.Iterable<Batch> getData(NDManager manager,
                                         java.util.concurrent.ExecutorService executorService)
                                  throws java.io.IOException,
                                         TranslateException

Fetches an iterator that can iterate through the Dataset with multiple threads.

Specified by:

getData in interface Dataset

Parameters:

manager - the dataset to iterate through

executorService - the executorService to use for multi-threading

Returns:

an Iterable of Batch that contains batches of data from the dataset

Throws:

java.io.IOException - for various exceptions depending on the dataset

TranslateException - if there is an error while processing input

getData

public java.lang.Iterable<Batch> getData(NDManager manager,
                                         Sampler sampler)
                                  throws java.io.IOException,
                                         TranslateException

Fetches an iterator that can iterate through the Dataset with a custom sampler.

Parameters:

manager - the dataset to iterate through

sampler - the sampler to use to iterate through the dataset

Returns:

an Iterable of Batch that contains batches of data from the dataset

Throws:

java.io.IOException - for various exceptions depending on the dataset

TranslateException - if there is an error while processing input

getData

public java.lang.Iterable<Batch> getData(NDManager manager,
                                         Sampler sampler,
                                         java.util.concurrent.ExecutorService executorService)
                                  throws java.io.IOException,
                                         TranslateException

Fetches an iterator that can iterate through the Dataset with a custom sampler multi-threaded.

Parameters:

manager - the dataset to iterate through

sampler - the sampler to use to iterate through the dataset

executorService - the executorService to multi-thread with

Returns:

an Iterable of Batch that contains batches of data from the dataset

Throws:

java.io.IOException - for various exceptions depending on the dataset

TranslateException - if there is an error while processing input

size

public long size()

Returns the size of this Dataset.

Returns:

the size of this Dataset

availableSize

protected abstract long availableSize()

Returns the number of records available to be read in this Dataset.

Returns:

the number of records available to be read in this Dataset

randomSplit

public RandomAccessDataset[] randomSplit(int... ratio)
                                  throws java.io.IOException,
                                         TranslateException

Splits the dataset set into multiple portions.

Parameters:

ratio - the ratio of each sub dataset

Returns:

an array of the sub dataset

Throws:

java.io.IOException - for various exceptions depending on the dataset

TranslateException - if there is an error while processing input

subDataset

public RandomAccessDataset subDataset(int fromIndex,
                                      int toIndex)

Returns a view of the portion of this data between the specified fromIndex, inclusive, and toIndex, exclusive.

Parameters:

fromIndex - low endpoint (inclusive) of the subDataset

toIndex - high endpoint (exclusive) of the subData

Returns:

a view of the specified range within this dataset

toArray

public ai.djl.util.Pair<java.lang.Number[][],java.lang.Number[][]> toArray()
                                                                          throws java.io.IOException,
                                                                                 TranslateException

Returns the dataset contents as a Java array.

Each Number[] is a flattened dataset record and the Number[][] is the array of all records.

Returns:

the dataset contents as a Java array

Throws:

java.io.IOException - for various exceptions depending on the dataset

TranslateException - if there is an error while processing input