Poly Class Template Reference

Class template interpolates tabulated data with polynomials. More...

#include <Intp.h>

Inherits Intp< xType, yType >.

Inheritance diagram for Poly:

[legend]List of all members.

Public Member Functions
virtual yType	eval (xType x) throw (IntpErr)
xType	getError (void) const
	Poly (const Intp< xType, yType > &in)
	Poly (const Poly< xType, yType > &po)
	Poly (const xType *arX, const yType *arY, int nCount, int nPoints=DEF_POINTS)
bool	setCount (int nPoints)
	~Poly (void)
Static Public Attributes
static const int	DEF_POINTS = 4

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Detailed Description

template<typename xType, typename yType>
class calc::Poly< xType, yType >

Class template interpolates tabulated data with polynomials.

In instantiation, an object is supplied with a one-dimensional set of independent variable and corresponding dependent variable data tables with a specific domain and range. The dependent data must be defined at every independent data point, continuous, and single-valued. When the interpolation object is evaluated within the data table domain, an interpolation value is calculated and returned. Fixed degree polynomials of a user-specified number are used for interpolation. A polynomial curve is calculated to fit sequential data points. The data point count of the curve is based on the order of the polynomial.

The declaration typename <xType> specifies the form of independent variables used in interpolation calculations. The declaration typename <yType> specifies the form of solution variables used in interpolation calculations. In general, the <yType> variables should be the equal or superset of the <xType> variables.

Author

efgeorge

Date

2006/07/19 13:21:43

Revision

1.3

Examples:

example_Intp.txt.

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Constructor & Destructor Documentation

Poly	(	const xType *	arX,
		const yType *	arY,
		int	nCount,
		int	nPoints = DEF_POINTS
	)

Constructor initializes a polynomial interpolation object.

Parameters:

	arX	a pointer to an independent value interpolation array (x units)
	arY	a pointer to a dependent value interpolation array (y units)
	nCount	data count for the specified arrays arX and arY
	nPoints	data point count of polynomials used in interpolation evaluations (optional)

Remarks:

• The data count value nCount must be greater than zero.
• The polynomial point count value nPoints must be greater than zero.
• The value nPoints should, be at most, equal to the data count value nCount.
• If the value nPoints is not specified, a default value of Poly::DEF_POINTS is used, and may be decreased based on the data count value nCount.
• The degree of polynomials used in interpolation evaluations is one less than the polynomial point count.

Poly

(

const Poly< xType, yType > &

po

)

Copy constructor initializes a polynomial interpolation object from the specified existing polynomial interpolation object.

Parameters:

po

a reference to a polynomial interpolation object

Poly

(

const Intp< xType, yType > &

in

)

Copy constructor initializes a polynomial interpolation object from the specified existing interpolation object.

Parameters:

in

a reference to an interpolation object

Remarks:

• The existing interpolation polynomial data point count is is transferred to the new interpolation object.
• Cube interpolation objects carry an existing interpolation polynomial data point count of Cube::DEF_POINTS.

~Poly

(

void

)

Destructor frees allocated memory.

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Member Function Documentation

yType eval

(

xType

x

)

throw (IntpErr) [virtual]

Virtual function interpolates the dependent data at the specified independent data value.

Parameters:

x

an independent value interpolation point (x units)

Returns:

calculated interpolation value evaluated at value x (y units)

Exceptions:

IntpErr

type of object thrown object initialization error (IntpErr::getIndex() = IntpErr::INIT) some independent data points are equal or decreasing (IntpErr::getIndex() = IntpErr::EQUAL)

Implements Intp.

xType getError

(

void

)

const

Function returns an error estimate to the last polynomial evaluation made through a call to Poly::eval().

Returns:

an error estimate to the polynomial interpolation (|y| units)

bool setCount

(

int

nPoints

)

Function sets the number of data points used in polynomial interpolation evaluations.

Parameters:

nPoints

the point count of interpolation polynomials

Returns:

status flag

• false (successful execution)
• true (execution error, parameter not set)

Remarks:

• The polynomial point count value nPoints must be greater than zero and less than or equal to the data count value of the independent and dependent interpolation arrays.
• The degree of polynomials used in interpolation evaluations is one less than the polynomial point count.

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Member Data Documentation

const int DEF_POINTS = 4 [static]

default interpolation polynomial data point count

Reimplemented from Intp.

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

• Intp.h
• Poly.cpp

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