uk.ac.starlink.ttools.plot2

Class DataPosSequence

java.lang.Object

uk.ac.starlink.ttools.plot2.DataPosSequence

All Implemented Interfaces:

CoordSequence, Sequence, Splittable<CoordSequence>

public class DataPosSequence
extends Object
implements CoordSequence

Splittable iterator over the data positions in a list of PositionClouds.

Since:

13 Sep 2019

Author:

Mark Taylor

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	DataPosSequence.PositionCloud Adaptor interface defining a cloud of positions for use with DataPosSequence.

Constructor Summary

Constructors

Constructor and Description
DataPosSequence(int ndim, DataPosSequence.PositionCloud[] clouds, DataStore dataStore) Constructor.

Method Summary

Modifier and Type	Method and Description
double[]	getCoords() Returns the array used to store the coordinates for the current position in this sequence.
boolean	next() Advances to the next entry.
DataPosSequence	split() Attempts to partition this object into two halves, ideally of similar size.
long	splittableSize() Provides an estimate of the number of processable items in this object.

Methods inherited from class java.lang.Object

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

Constructor Detail

DataPosSequence

public DataPosSequence(int ndim,
                       DataPosSequence.PositionCloud[] clouds,
                       DataStore dataStore)

Constructor.

Parameters:

ndim - coordinate dimensionality

clouds - list of point clouds providing positions over which to iterate

dataStore - data storage object

Method Detail

getCoords

public double[] getCoords()

Description copied from interface: CoordSequence

Returns the array used to store the coordinates for the current position in this sequence. It contains the coordinates corresponding to the last call of the CoordSequence.next() method. Its contents before the first call or after a call returning false are undefined.

This method returns the same value throughout the lifetime of this sequence, it's only the contents that change to reflect the current state of the iteration.

Specified by:

getCoords in interface CoordSequence

next

public boolean next()

Description copied from interface: CoordSequence

Advances to the next entry. No exception is thrown.

Specified by:

next in interface CoordSequence

Specified by:

next in interface Sequence

Returns:

true iff the current sequence element has data

split

public DataPosSequence split()

Description copied from interface: Splittable

Attempts to partition this object into two halves, ideally of similar size. If a non-null value is returned, then the content previously contained by this object is now split between this object and the returned object. If for any reason a split is not carried out, null is returned.

Following a successful call, the two parts may be processed in different threads.

Specified by:

split in interface Splittable<CoordSequence>

Returns:

other half of this splittable, or null

See Also:

Spliterator.trySplit()

splittableSize

public long splittableSize()

Description copied from interface: Splittable

Provides an estimate of the number of processable items in this object. A processable item is not a well-defined quantity, but it should generally be something that can be processed fast. For instance, if this object represents a collection of collections, the value that should be returned is the total number of elements rather than the number of collections.

If no estimate for the size is available, a negative value should be returned.

Specified by:

splittableSize in interface Splittable<CoordSequence>

Returns:

approximate size, or negative value if not known