votca::tools::Spline Class Reference

Spline Class. More...

#include <spline.h>

Inheritance diagram for votca::tools::Spline:

Public Types
enum	eBoundary { splineNormal = 0 , splinePeriodic = 1 , splineDerivativeZero = 2 }
	enum for type of boundary condition More...

Public Member Functions
	Spline ()=default
virtual	~Spline ()=default
virtual void	Interpolate (const Eigen::VectorXd &x, const Eigen::VectorXd &y)=0
	Calculate interpolating spline for given (x,y) values. Points on resulting spline can be obtained via Calculate().
virtual void	Fit (const Eigen::VectorXd &x, const Eigen::VectorXd &y)=0
	Fit spline through noisy (x,y) values. Points on resulting fitted spline can be obtained via Calculate().
virtual double	Calculate (double x)=0
	Calculate spline function value for a given x value on the spline created by Interpolate() or Fit()
virtual double	CalculateDerivative (double x)=0
	Calculate y value for a given x value on the derivative of the spline created by function Interpolate or Fit.
void	setBC (eBoundary bc)
	Set the boundary type of the spline.
void	setBCInt (Index bc)
	Set the boundary type of the spline.
double	getGridPoint (int i)
	Get the grid point of certain index.
Eigen::VectorXd	Calculate (const Eigen::VectorXd &x)
	Calculate spline function values for given x values on the spline created by Interpolate() or Fit()
Eigen::VectorXd	CalculateDerivative (const Eigen::VectorXd &x)
	Calculate y values for given x values on the derivative of the spline created by function Interpolate or Fit.
void	Print (std::ostream &out, double interval)
	Print spline values (using Calculate()) on output "out" on the entire grid in steps of "interval".
Index	getInterval (double r)
	Determine the index of the interval containing value r.
Index	GenerateGrid (double min, double max, double h)
	Generate the grid for fitting from "min" to "max" in steps of "h".
Eigen::VectorXd &	getX ()
	Get the grid array x.
const Eigen::VectorXd &	getX () const

Protected Attributes
eBoundary	boundaries_ = eBoundary::splineNormal
	Get the spline data f_.
Eigen::VectorXd	r_

Detailed Description

Spline Class.

class supports spline interpolation and fit of data the cubic spline class, akima spline class and linear spline class are inherited from this one

Definition at line 36 of file spline.h.

Member Enumeration Documentation

eBoundary

enum votca::tools::Spline::eBoundary

enum for type of boundary condition

Enumerator
splineNormal	normal boundary conditions: \(f_0=f_N=0\)
splinePeriodic	periodic boundary conditions: \(f_0=f_N\)
splineDerivativeZero	derivatives and end-points are zero.

Definition at line 73 of file spline.h.

Constructor & Destructor Documentation

Spline()

votca::tools::Spline::Spline ( )

default

~Spline()

virtual votca::tools::Spline::~Spline ( )

virtualdefault

Member Function Documentation

Calculate() [1/2]

Eigen::VectorXd votca::tools::Spline::Calculate

(

const Eigen::VectorXd &

x

)

Calculate spline function values for given x values on the spline created by Interpolate() or Fit()

Parameters

x	vector of data values

Returns

vector of y value

Definition at line 40 of file spline.cc.

Calculate() [2/2]

virtual double votca::tools::Spline::Calculate ( double x )

pure virtual

Calculate spline function value for a given x value on the spline created by Interpolate() or Fit()

Parameters

x	data value

Returns

y value

Implemented in votca::tools::AkimaSpline, votca::tools::CubicSpline, and votca::tools::LinSpline.

CalculateDerivative() [1/2]

Eigen::VectorXd votca::tools::Spline::CalculateDerivative

(

const Eigen::VectorXd &

x

)

Calculate y values for given x values on the derivative of the spline created by function Interpolate or Fit.

Parameters

x	vector of data values

Returns

vector of y value

Definition at line 48 of file spline.cc.

CalculateDerivative() [2/2]

virtual double votca::tools::Spline::CalculateDerivative ( double x )

pure virtual

Calculate y value for a given x value on the derivative of the spline created by function Interpolate or Fit.

Parameters

x	data value

Returns

y value of derivative

Implemented in votca::tools::AkimaSpline, votca::tools::CubicSpline, and votca::tools::LinSpline.

Fit()

virtual void votca::tools::Spline::Fit ( const Eigen::VectorXd & x, const Eigen::VectorXd & y )

pure virtual

Fit spline through noisy (x,y) values. Points on resulting fitted spline can be obtained via Calculate().

Parameters

x	values of data to be fitted
y	values of data to be fitted both vectors must be of same size

Implemented in votca::tools::AkimaSpline, votca::tools::CubicSpline, and votca::tools::LinSpline.

GenerateGrid()

Index votca::tools::Spline::GenerateGrid	(	double	min,
		double	max,
		double	h )

Generate the grid for fitting from "min" to "max" in steps of "h".

Parameters

min	left interval border
max	right interval border
h	step

Returns

number of grid values in the interval

Definition at line 26 of file spline.cc.

getGridPoint()

double votca::tools::Spline::getGridPoint

(

int

i

)

Get the grid point of certain index.

Parameters

i	index of grid point

Returns

grid value

Definition at line 78 of file spline.cc.

getInterval()

Index votca::tools::Spline::getInterval

(

double

r

)

Determine the index of the interval containing value r.

Parameters

r

Returns

interval index

Definition at line 62 of file spline.cc.

getX() [1/2]

Eigen::VectorXd & votca::tools::Spline::getX ( )

inline

Get the grid array x.

Returns

pointer to the corresponding array

Definition at line 154 of file spline.h.

getX() [2/2]

const Eigen::VectorXd & votca::tools::Spline::getX ( ) const

inline

Definition at line 155 of file spline.h.

Interpolate()

virtual void votca::tools::Spline::Interpolate ( const Eigen::VectorXd & x, const Eigen::VectorXd & y )

pure virtual

Calculate interpolating spline for given (x,y) values. Points on resulting spline can be obtained via Calculate().

Parameters

x	values of data to be interpolated
y	values of data to be interpolated both vectors must be of same size

Implemented in votca::tools::AkimaSpline, votca::tools::CubicSpline, and votca::tools::LinSpline.

Print()

void votca::tools::Spline::Print	(	std::ostream &	out,
		double	interval )

Print spline values (using Calculate()) on output "out" on the entire grid in steps of "interval".

Parameters

out	output
interval	size of "interval"

Definition at line 56 of file spline.cc.

setBC()

void votca::tools::Spline::setBC ( eBoundary bc )

inline

Set the boundary type of the spline.

Parameters

bc	of type eBoundary

Definition at line 83 of file spline.h.

setBCInt()

void votca::tools::Spline::setBCInt ( Index bc )

inline

Set the boundary type of the spline.

Parameters

bc	of type Index

Definition at line 89 of file spline.h.

Member Data Documentation

boundaries_

eBoundary votca::tools::Spline::boundaries_ = eBoundary::splineNormal

protected

Get the spline data f_.

Returns

reference to the corresponding array

Get second derivatives (cubic splines)

Returns

reference to the corresponding array

Definition at line 171 of file spline.h.

r_

Eigen::VectorXd votca::tools::Spline::r_

protected

Definition at line 173 of file spline.h.

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

• tools/include/votca/tools/spline.h
• tools/src/libtools/spline.cc