imath::CAkimaInterpolator Class Reference

1D interpolation using the Akima method for smooth, natural-looking curves. More...

#include <CAkimaInterpolator.h>

Inheritance diagram for imath::CAkimaInterpolator:

Classes
struct	Node

Public Types
typedef QMap< double, Node >	Nodes
Public Types inherited from imath::TIMathFunction< Argument, Result >
typedef Argument	ArgumentType
typedef Result	ResultType

Public Member Functions
	CAkimaInterpolator ()
	CAkimaInterpolator (double *positions, double *values, int nodesCount)
void	SetNodes (double *positions, double *values, int nodesCount)
virtual bool	InitFromFunction (const ISampledFunction &function) override
	Initialize interpolator based on a sample function.
virtual bool	GetValueAt (const double &argument, double &result) const override
virtual double	GetValueAt (const double &argument) const override
Public Member Functions inherited from imath::TIMathFunction< Argument, Result >
virtual bool	GetValueAt (const Argument &argument, Result &result) const =0
	Get function value for specified argument value.
virtual Result	GetValueAt (const Argument &argument) const =0
	Get function value for specified argument value.
Public Member Functions inherited from istd::IPolymorphic
virtual	~IPolymorphic ()

Protected Attributes
Nodes	m_nodes

Detailed Description

1D interpolation using the Akima method for smooth, natural-looking curves.

Purpose

CAkimaInterpolator provides smooth interpolation through a set of data points using the Akima spline method. This method produces curves that are less prone to oscillation than cubic splines, making it particularly suitable for visualizing scientific data or creating smooth transitions in animations and simulations.

Characteristics

• Smoothness: C1 continuous (continuous first derivative)
• Locality: Changes to one data point only affect nearby segments
• No overshooting: Less prone to oscillation compared to cubic splines
• Natural appearance: Produces visually pleasing curves for most datasets

Usage Examples

// Create interpolator from data arrays
double positions[] = {0.0, 1.0, 2.0, 3.0, 4.0};
double values[] = {0.0, 1.0, 0.5, 2.0, 1.5};
imath::CAkimaInterpolator interpolator(positions, values, 5);
 
// Interpolate at arbitrary positions
double result;
if (interpolator.GetValueAt(1.5, result)) {
       // result contains interpolated value at x=1.5
}
 
// Or use direct access
double value = interpolator.GetValueAt(2.3);
 
// Initialize from ISampledFunction
// (if you have function data in that format)
// interpolator.InitFromFunction(sampledFunction);

Akima vs Linear Interpolation

• Akima: Smooth curves, C1 continuous, better for visualization
• Linear: Piecewise linear, simpler, better for data with sharp transitions

Choose Akima interpolation when:

• You need smooth, natural-looking curves
• Data represents continuous physical phenomena
• Visual quality is important
• Data points are reasonably spaced

See also

imath::CLinearInterpolator, imath::ISampledFunctionInterpolator

Definition at line 66 of file CAkimaInterpolator.h.

Member Typedef Documentation

Nodes

typedef QMap<double, Node> imath::CAkimaInterpolator::Nodes

Definition at line 75 of file CAkimaInterpolator.h.

Constructor & Destructor Documentation

CAkimaInterpolator() [1/2]

imath::CAkimaInterpolator::CAkimaInterpolator

(

)

CAkimaInterpolator() [2/2]

imath::CAkimaInterpolator::CAkimaInterpolator	(	double *	positions,
		double *	values,
		int	nodesCount
	)

Member Function Documentation

GetValueAt() [1/2]

virtual double imath::CAkimaInterpolator::GetValueAt ( const double &  argument ) const

overridevirtual

GetValueAt() [2/2]

virtual bool imath::CAkimaInterpolator::GetValueAt ( const double &  argument, double &  result  ) const

overridevirtual

InitFromFunction()

virtual bool imath::CAkimaInterpolator::InitFromFunction ( const ISampledFunction &  function )

overridevirtual

Initialize interpolator based on a sample function.

Implements imath::ISampledFunctionInterpolator.

SetNodes()

void imath::CAkimaInterpolator::SetNodes	(	double *	positions,
		double *	values,
		int	nodesCount
	)

Member Data Documentation

m_nodes

Nodes imath::CAkimaInterpolator::m_nodes

protected

Definition at line 90 of file CAkimaInterpolator.h.

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The documentation for this class was generated from the following file:

• Acf/Include/imath/CAkimaInterpolator.h