IlvCallbackChartFunction Class Reference

Class for data sets described by a callback function. More...

#include <ilviews/charts/data.h>

Inheritance diagram for IlvCallbackChartFunction:

List of all members.

Public Member Functions
	IlvCallbackChartFunction (const IlvCoordInterval &xRange, IlUInt count, IlvDoubleFunction f, const char *name=0, IlvPointInfoCollection *ptInfoCollection=0)
	Constructor.
	IlvCallbackChartFunction (const char *name=0, IlvPointInfoCollection *ptInfoCollection=0)
	Constructor.
IlvDoubleFunction	getFunction () const
	Returns the function used to describe the data points.
virtual void	getPoint (IlUInt i, IlvDoublePoint &point) const
	Returns a data point.
virtual IlBoolean	isFunctionDefined () const
	Indicates whether the function describing the data is defined.
void	setFunction (IlvDoubleFunction function)
	Sets the function used to describe the data points.

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Detailed Description

Class for data sets described by a callback function.

Library: ilvcharts

This class is a subclass of IlvAbstractChartFunction for which the data points are described by a function of the type y = f(x) defined by a callback. The used callback must be of the type IlvDoubleFunction.

The abscissa of the nth data point of the data set is obtained by the following formula:

 x = ((_xMax - _xMin) / (_dataCount -1)) * i + _xMin,

where _xMin and _xMax are the minimum and the maximum values considered for the abscissa and _dataCount is the number of considered data points. The ordinate is equal to f(x).

See also:

IlvAbstractChartFunction, IlvDoubleFunction, IlvPointInfoCollection.

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Constructor & Destructor Documentation

IlvCallbackChartFunction::IlvCallbackChartFunction	(	const char *	name = 0,
		IlvPointInfoCollection *	ptInfoCollection = 0
	)

Constructor.

Initializes a new IlvCallbackChartFunction object. The function and the data count are set by default to 0.

Parameters:

	name	If not 0, this string becomes the name of the created data set. The name passed as a parameter is copied.
	ptInfoCollection	The object used to manage the point information for the created data set.

IlvCallbackChartFunction::IlvCallbackChartFunction	(	const IlvCoordInterval &	xRange,
		IlUInt	count,
		IlvDoubleFunction	f,
		const char *	name = 0,
		IlvPointInfoCollection *	ptInfoCollection = 0
	)

Constructor.

Initializes a new IlvCallbackChartFunction object.

Parameters:

	xRange	The values interval considered for the abscissa.
	count	The data count.
	f	The function used to define the data points.
	name	If not 0, this string becomes the name of the created data set. The name passed as a parameter is copied.
	ptInfoCollection	The object used to manage the point information of the created data set.

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Member Function Documentation

IlvDoubleFunction IlvCallbackChartFunction::getFunction

(

)

const

Returns the function used to describe the data points.

Returns:

The function used to describe the data points for the considered data set.

Warning:

[note] This function is a callback of the type IlvDoubleFunction.

virtual void IlvCallbackChartFunction::getPoint	(	IlUInt	i,
		IlvDoublePoint &	point
	)			const [virtual]

Returns a data point.

Returns in point the point of index i for the current data set. This point is defined as follows:

 IlDouble x = ((_xMax - _xMin) / ( _dataCount -1)) * i + _xMin;
 IlDouble y = _function ? _function(x) : _yMin;
 point.x(x);
 point.y(y);

where _xMin and _xMax are the minimum and the maximum values considered for the abscissa, _dataCount is the number of considered data points, _function the defined function, and _yMin the minimum value of the ordinate for all the considered data.

Parameters:

	i	The index of the returned data point.
	point	The returned data point.

Implements IlvChartDataSet.

virtual IlBoolean IlvCallbackChartFunction::isFunctionDefined

(

)

const [virtual]

Indicates whether the function describing the data is defined.

Returns:

IlTrue if the function describing the data is defined and IlFalse otherwise.

Reimplemented from IlvAbstractChartFunction.

void IlvCallbackChartFunction::setFunction

(

IlvDoubleFunction

function

)

Sets the function used to describe the data points.

Parameters:

function

The new function used to describe the data points of the current data set. This function should be a callback of the type IlvDoubleFunction.