Class RollingPointPairList

A class that provides a rolling list of PointPair objects. This is essentially a first-in-first-out (FIFO) queue with a fixed capacity which allows 'rolling' (or oscilloscope like) graphs to be be animated without having the overhead of an ever-growing ArrayList.

The queue is constructed with a fixed capacity and new points can be enqueued. When the capacity is reached the oldest (first in) PointPair is overwritten. However, when accessing via IPointList, the PointPair objects are seen in the order in which they were enqeued.

RollingPointPairList supports data editing through the IPointListEdit interface.

Colin Green with mods by John Champion $Date: 2007-11-05 04:33:26 $

Inheritance

Object

RollingPointPairList

Implements

ISerializable

IPointListEdit

IPointList

ICloneable

Inherited Members

Object.Equals(Object)

Object.Equals(Object, Object)

Object.GetHashCode()

Object.GetType()

Object.MemberwiseClone()

Object.ReferenceEquals(Object, Object)

Object.ToString()

Namespace: ZedGraph

Assembly: ZedGraph.dll

Syntax

[Serializable]
public class RollingPointPairList : ISerializable, IPointListEdit, IPointList, ICloneable

Constructors

RollingPointPairList(Int32)

Constructs an empty buffer with the specified capacity.

Declaration

public RollingPointPairList(int capacity)

Parameters

Type	Name	Description
Int32	capacity	Number of elements in the rolling list. This number cannot be changed once the RollingPointPairList is constructed.

RollingPointPairList(Int32, Boolean)

Constructs an empty buffer with the specified capacity. Pre-allocates space for all PointPair's in the list if preLoad is true.

Declaration

public RollingPointPairList(int capacity, bool preLoad)

Parameters

Type	Name	Description
Int32	capacity	Number of elements in the rolling list. This number cannot be changed once the RollingPointPairList is constructed.
Boolean	preLoad	true to pre-allocate all PointPair instances in the list, false otherwise. Note that in order to be memory efficient, the Add(Double, Double, Double) method should be used to add data. Avoid the Add(PointPair) method.

See Also

Add(Double, Double, Double)

RollingPointPairList(SerializationInfo, StreamingContext)

Constructor for deserializing objects

Declaration

protected RollingPointPairList(SerializationInfo info, StreamingContext context)

Parameters

Type	Name	Description
SerializationInfo	info	A SerializationInfo instance that defines the serialized data
StreamingContext	context	A StreamingContext instance that contains the serialized data

RollingPointPairList(IPointList)

Constructs a buffer with a copy of the items within the provided IPointList. The Capacity is set to the length of the provided list.

Declaration

public RollingPointPairList(IPointList rhs)

Parameters

Type	Name	Description
IPointList	rhs	The IPointList to be copied.

Fields

_headIdx

The index of the previously enqueued item. -1 if buffer is empty.

Declaration

[CLSCompliant(false)]
protected int _headIdx

Field Value

Type	Description
Int32

_mBuffer

An array of PointPair objects that acts as the underlying buffer.

Declaration

[CLSCompliant(false)]
protected PointPair[] _mBuffer

Field Value

Type	Description
PointPair[]

_tailIdx

The index of the next item to be dequeued. -1 if buffer is empty.

Declaration

[CLSCompliant(false)]
protected int _tailIdx

Field Value

Type	Description
Int32

schema

Current schema value that defines the version of the serialized file

Declaration

public const int schema = 10

Field Value

Type	Description
Int32

Properties

Capacity

Gets the capacity of the rolling buffer.

Declaration

public int Capacity { get; }

Property Value

Type	Description
Int32

Count

Gets the count of items within the rolling buffer. Note that this may be less than the capacity.

Declaration

public int Count { get; }

Property Value

Type	Description
Int32

IsEmpty

Gets a bolean that indicates if the buffer is empty. Alternatively you can test Count==0.

Declaration

public bool IsEmpty { get; }

Property Value

Type	Description
Boolean

Item[Int32]

Gets or sets the PointPair at the specified index in the buffer.

Declaration

public PointPair this[int index] { get; set; }

Parameters

Type	Name	Description
Int32	index

Property Value

Type	Description
PointPair

Remarks

Index must be within the current size of the buffer, e.g., the set method will not expand the buffer even if Capacity is available

Methods

Add(Double, Double)

Add a set of values onto the head of the queue, overwriting old values if the buffer is full.

Declaration

public void Add(double x, double y)

Parameters

Type	Name	Description
Double	x	The X value
Double	y	The Y value

Remarks

This method is much more efficient that the Add(PointPair) method, since it does not require that a new PointPair instance be provided. If the buffer already contains a PointPair at the head position, then the x, y, z, and tag values will be copied into the existing PointPair. Otherwise, a new PointPair instance must be created. In this way, each PointPair position in the rolling list will only be allocated one time. To truly be memory efficient, the Remove(), RemoveAt(Int32), and Pop() methods should be avoided.

Add(Double, Double, Double)

Add a set of values onto the head of the queue, overwriting old values if the buffer is full.

Declaration

public void Add(double x, double y, double z)

Parameters

Type	Name	Description
Double	x	The X value
Double	y	The Y value
Double	z	The Z value

Remarks

This method is much more efficient that the Add(PointPair) method, since it does not require that a new PointPair instance be provided. If the buffer already contains a PointPair at the head position, then the x, y, z, and tag values will be copied into the existing PointPair. Otherwise, a new PointPair instance must be created. In this way, each PointPair position in the rolling list will only be allocated one time. To truly be memory efficient, the Remove(), RemoveAt(Int32), and Pop() methods should be avoided.

Add(Double, Double, Double, Object)

Add a set of values onto the head of the queue, overwriting old values if the buffer is full.

Declaration

public void Add(double x, double y, double z, object tag)

Parameters

Type	Name	Description
Double	x	The X value
Double	y	The Y value
Double	z	The Z value
Object	tag	The Tag value for the PointPair

Remarks

This method is much more efficient that the Add(PointPair) method, since it does not require that a new PointPair instance be provided. If the buffer already contains a PointPair at the head position, then the x, y, z, and tag values will be copied into the existing PointPair. Otherwise, a new PointPair instance must be created. In this way, each PointPair position in the rolling list will only be allocated one time. To truly be memory efficient, the Remove(), RemoveAt(Int32), and Pop() methods should be avoided. Also, the tag property for this method should be null, since it is a reference type.

Add(Double, Double, Object)

Add a set of values onto the head of the queue, overwriting old values if the buffer is full.

Declaration

public void Add(double x, double y, object tag)

Parameters

Type	Name	Description
Double	x	The X value
Double	y	The Y value
Object	tag	The Tag value for the PointPair

Remarks

This method is much more efficient that the Add(PointPair) method, since it does not require that a new PointPair instance be provided. If the buffer already contains a PointPair at the head position, then the x, y, z, and tag values will be copied into the existing PointPair. Otherwise, a new PointPair instance must be created. In this way, each PointPair position in the rolling list will only be allocated one time. To truly be memory efficient, the Remove(), RemoveAt(Int32), and Pop() methods should be avoided. Also, the tag property for this method should be null, since it is a reference type.

Add(Double[], Double[])

Add a set of points to the RollingPointPairList from two arrays of type double. If either array is null, then a set of ordinal values is automatically generated in its place (see Ordinal). If the arrays are of different size, then the larger array prevails and the smaller array is padded with Missing values.

Declaration

public void Add(double[] x, double[] y)

Parameters

Type	Name	Description
Double[]	x	A double[] array of X values
Double[]	y	A double[] array of Y values

Add(Double[], Double[], Double[])

Add a set of points to the RollingPointPairList from three arrays of type double. If the X or Y array is null, then a set of ordinal values is automatically generated in its place (see Ordinal. If the value is null, then it is set to zero. If the arrays are of different size, then the larger array prevails and the smaller array is padded with Missing values.

Declaration

public void Add(double[] x, double[] y, double[] z)

Parameters

Type	Name	Description
Double[]	x	A double[] array of X values
Double[]	y	A double[] array of Y values
Double[]	z	A double[] array of Z values

Add(IPointList)

Add an IPointList object to the head of the queue.

Declaration

public void Add(IPointList pointList)

Parameters

Type	Name	Description
IPointList	pointList	A reference to the IPointList object to be added

Add(PointPair)

Add a PointPair onto the head of the queue, overwriting old values if the buffer is full.

Declaration

public void Add(PointPair item)

Parameters

Type	Name	Description
PointPair	item	The PointPair to be added.

Clear()

Clear the buffer of all PointPair objects. Note that the Capacity remains unchanged.

Declaration

public void Clear()

Clone()

Typesafe, deep-copy clone method.

Declaration

public RollingPointPairList Clone()

Returns

Type	Description
RollingPointPairList	A new, independent copy of this class

GetObjectData(SerializationInfo, StreamingContext)

Populates a SerializationInfo instance with the data needed to serialize the target object

Declaration

[SecurityPermission(SecurityAction.Demand, SerializationFormatter = true)]
public virtual void GetObjectData(SerializationInfo info, StreamingContext context)

Parameters

Type	Name	Description
SerializationInfo	info	A SerializationInfo instance that defines the serialized data
StreamingContext	context	A StreamingContext instance that contains the serialized data

Peek()

Peek at the PointPair item at the head of the queue.

Declaration

public PointPair Peek()

Returns

Type	Description
PointPair	The PointPair item at the head of the queue. Throws an InvalidOperationException if the buffer was empty.

Pop()

Pop an item off the head of the queue.

Declaration

public PointPair Pop()

Returns

Type	Description
PointPair	The popped item. Throws an exception if the buffer was empty.

Remove()

Remove an old item from the tail of the queue.

Declaration

public PointPair Remove()

Returns

Type	Description
PointPair	The removed item. Throws an InvalidOperationException if the buffer was empty. Check the buffer's length (Count) or the IsEmpty property to avoid exceptions.

RemoveAt(Int32)

Remove the PointPair at the specified index

Declaration

public void RemoveAt(int index)

Parameters

Type	Name	Description
Int32	index	The ordinal position of the item to be removed. Throws an ArgumentOutOfRangeException if index is less than zero or greater than or equal to Count

Remarks

All items in the queue that lie after index will be shifted back by one, and the queue will be one item shorter.

RemoveRange(Int32, Int32)

Remove a range of PointPair objects starting at the specified index

Declaration

public void RemoveRange(int index, int count)

Parameters

Type	Name	Description
Int32	index	The ordinal position of the item to be removed. Throws an ArgumentOutOfRangeException if index is less than zero or greater than or equal to Count
Int32	count	The number of items to be removed. Throws an ArgumentOutOfRangeException if count is less than zero or greater than the total available items in the queue

Remarks

All items in the queue that lie after index will be shifted back, and the queue will be count items shorter.

Explicit Interface Implementations

ICloneable.Clone()

Implement the ICloneable interface in a typesafe manner by just calling the typed version of Clone()

Declaration

object ICloneable.Clone()

Returns

Type	Description
Object	A deep copy of this object

Implements

System.Runtime.Serialization.ISerializable

IPointListEdit

IPointList

System.ICloneable