org.openimaj.data

Class DoubleArrayBackedDataSource

java.lang.Object

org.openimaj.data.DoubleArrayBackedDataSource

All Implemented Interfaces:

Iterable<double[]>, DataSource<double[]>

public class DoubleArrayBackedDataSource
extends Object
implements DataSource<double[]>

A DataSource backed by a 2D array of doubles.

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Field Summary

Fields

Modifier and Type	Field and Description
protected double[][]	data
protected Random	rng

Constructor Summary

Constructors

Constructor and Description
DoubleArrayBackedDataSource(double[][] data) Construct with data
DoubleArrayBackedDataSource(double[][] data, Random rng) Construct with data and a random generator for random sampling

Method Summary

Modifier and Type	Method and Description
double[][]	createTemporaryArray(int size) Create a temporary array suitable for use with the DataSource.getRandomRows(Object[]) and DataSource.getData(int, int, Object[]) methods.
double[]	getData(int row) Get the data for a given row
void	getData(int startRow, int stopRow, double[][] output) Get data between given rows.
void	getRandomRows(double[][] output)
Iterator<double[]>	iterator()
int	numDimensions()
int	size()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

data

protected double[][] data

rng

protected Random rng

Constructor Detail

DoubleArrayBackedDataSource

public DoubleArrayBackedDataSource(double[][] data)

Construct with data

Parameters:

data - the data

DoubleArrayBackedDataSource

public DoubleArrayBackedDataSource(double[][] data,
                                   Random rng)

Construct with data and a random generator for random sampling

Parameters:

data - the data

rng - the random generator

Method Detail

getData

public final void getData(int startRow,
                          int stopRow,
                          double[][] output)

Description copied from interface: DataSource

Get data between given rows. startRow must be > 0, stopRow must be smaller than DataSource.size(). data is guaranteed to have (stopRow - startRow) valid entries

Specified by:

getData in interface DataSource<double[]>

Parameters:

startRow - where to start (inclusive)

stopRow - where to stop (exclusive)

output - the array to fill

getRandomRows

public final void getRandomRows(double[][] output)

Specified by:

getRandomRows in interface DataSource<double[]>

Parameters:

output - a random set of data. This array is guaranteed to be filled.

numDimensions

public int numDimensions()

Specified by:

numDimensions in interface DataSource<double[]>

Returns:

Number of dimensions of each data point

size

public int size()

Specified by:

size in interface DataSource<double[]>

Returns:

the number of data points

getData

public double[] getData(int row)

Description copied from interface: DataSource

Get the data for a given row

Specified by:

getData in interface DataSource<double[]>

Parameters:

row - the row number

Returns:

the data for the row

iterator

public Iterator<double[]> iterator()

Specified by:

iterator in interface Iterable<double[]>

createTemporaryArray

public double[][] createTemporaryArray(int size)

Description copied from interface: DataSource

Create a temporary array suitable for use with the DataSource.getRandomRows(Object[]) and DataSource.getData(int, int, Object[]) methods.

Specified by:

createTemporaryArray in interface DataSource<double[]>

Parameters:

size - the size of the array

Returns:

the array