org.nd4j.linalg.dataset.api.iterator

Class SamplingDataSetIterator

java.lang.Object

org.nd4j.linalg.dataset.api.iterator.SamplingDataSetIterator

All Implemented Interfaces:

Serializable, Iterator<DataSet>, DataSetIterator

public class SamplingDataSetIterator
extends Object
implements DataSetIterator

A wrapper for a dataset to sample from. This will randomly sample from the given dataset.

Author:

Adam Gibson

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
SamplingDataSetIterator(DataSet sampleFrom, int batchSize, int totalNumberSamples)
SamplingDataSetIterator(DataSet sampleFrom, int batchSize, int totalNumberSamples, boolean replace)

Method Summary

Modifier and Type	Method and Description
boolean	asyncSupported() Does this DataSetIterator support asynchronous prefetching of multiple DataSet objects? Most DataSetIterators do, but in some cases it may not make sense to wrap this iterator in an iterator that does asynchronous prefetching.
int	batch() Batch size
int	cursor() The current cursor if applicable
List<String>	getLabels() Get dataset iterator record reader labels
DataSetPreProcessor	getPreProcessor() Returns preprocessors, if defined
boolean	hasNext()
int	inputColumns() Input columns for the dataset
DataSet	next()
DataSet	next(int num) Like the standard next method but allows a customizable number of examples returned
int	numExamples() Total number of examples in the dataset
void	remove()
void	reset() Resets the iterator back to the beginning
boolean	resetSupported() Is resetting supported by this DataSetIterator? Many DataSetIterators do support resetting, but some don't
void	setPreProcessor(DataSetPreProcessor preProcessor) Set a pre processor
int	totalExamples() Total examples in the iterator
int	totalOutcomes() The number of labels for the dataset

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining

Constructor Detail

SamplingDataSetIterator

public SamplingDataSetIterator(DataSet sampleFrom,
                               int batchSize,
                               int totalNumberSamples,
                               boolean replace)

Parameters:

sampleFrom - the dataset to sample from

batchSize - the batch size to sample

totalNumberSamples - the sample size

SamplingDataSetIterator

public SamplingDataSetIterator(DataSet sampleFrom,
                               int batchSize,
                               int totalNumberSamples)

Parameters:

sampleFrom - the dataset to sample from

batchSize - the batch size to sample

totalNumberSamples - the sample size

Method Detail

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<DataSet>

next

public DataSet next()

Specified by:

next in interface Iterator<DataSet>

remove

public void remove()

Specified by:

remove in interface Iterator<DataSet>

totalExamples

public int totalExamples()

Description copied from interface: DataSetIterator

Total examples in the iterator

Specified by:

totalExamples in interface DataSetIterator

Returns:

inputColumns

public int inputColumns()

Description copied from interface: DataSetIterator

Input columns for the dataset

Specified by:

inputColumns in interface DataSetIterator

Returns:

totalOutcomes

public int totalOutcomes()

Description copied from interface: DataSetIterator

The number of labels for the dataset

Specified by:

totalOutcomes in interface DataSetIterator

Returns:

resetSupported

public boolean resetSupported()

Description copied from interface: DataSetIterator

Is resetting supported by this DataSetIterator? Many DataSetIterators do support resetting, but some don't

Specified by:

resetSupported in interface DataSetIterator

Returns:

true if reset method is supported; false otherwise

asyncSupported

public boolean asyncSupported()

Description copied from interface: DataSetIterator

Does this DataSetIterator support asynchronous prefetching of multiple DataSet objects? Most DataSetIterators do, but in some cases it may not make sense to wrap this iterator in an iterator that does asynchronous prefetching. For example, it would not make sense to use asynchronous prefetching for the following types of iterators: (a) Iterators that store their full contents in memory already (b) Iterators that re-use features/labels arrays (as future next() calls will overwrite past contents) (c) Iterators that already implement some level of asynchronous prefetching (d) Iterators that may return different data depending on when the next() method is called

Specified by:

asyncSupported in interface DataSetIterator

Returns:

true if asynchronous prefetching from this iterator is OK; false if asynchronous prefetching should not be used with this iterator

reset

public void reset()

Description copied from interface: DataSetIterator

Resets the iterator back to the beginning

Specified by:

reset in interface DataSetIterator

batch

public int batch()

Description copied from interface: DataSetIterator

Batch size

Specified by:

batch in interface DataSetIterator

Returns:

cursor

public int cursor()

Description copied from interface: DataSetIterator

The current cursor if applicable

Specified by:

cursor in interface DataSetIterator

Returns:

numExamples

public int numExamples()

Description copied from interface: DataSetIterator

Total number of examples in the dataset

Specified by:

numExamples in interface DataSetIterator

Returns:

setPreProcessor

public void setPreProcessor(DataSetPreProcessor preProcessor)

Set a pre processor

Specified by:

setPreProcessor in interface DataSetIterator

Parameters:

preProcessor - a pre processor to set

getPreProcessor

public DataSetPreProcessor getPreProcessor()

Description copied from interface: DataSetIterator

Returns preprocessors, if defined

Specified by:

getPreProcessor in interface DataSetIterator

Returns:

getLabels

public List<String> getLabels()

Description copied from interface: DataSetIterator

Get dataset iterator record reader labels

Specified by:

getLabels in interface DataSetIterator

next

public DataSet next(int num)

Description copied from interface: DataSetIterator

Like the standard next method but allows a customizable number of examples returned

Specified by:

next in interface DataSetIterator

Parameters:

num - the number of examples

Returns:

the next data applyTransformToDestination