CubicSplineTest Class Reference

Unit test of class CubicSpline. More...

Inheritance diagram for CubicSplineTest:

Collaboration diagram for CubicSplineTest:

Protected Member Functions
	CubicSplineTest ()
	~CubicSplineTest ()=default
double	error_bound (int n, const double *x, const std::function< double(double)> &f, int d=0) const
	theoretical error bound for complete cubic spline
void	read (const std::string &fname, int &n, double *x, double *y, BoundaryCondition &bc_start, BoundaryCondition &bc_end, int &n_interp, double *x_interp, double *y_interp, double *dy_interp, double *d2y_interp) const

Protected Attributes
int	n_max_
	maximum number of knots
std::vector< double >	spline_
	buffer for a cubic spline (x_, y_ & dy_)
double *	x_
	knots (x-coordinates of data points)
double *	y_
	values at knots (y-coordinates of data points)
double *	dy_
	derivatives at knots (computed when building a cubic spline)
int	n_interp_max_
	maximum number of places to evaluate an interpolant
std::vector< double >	interp_
	buffer for interpolant evaluation
double *	x_interp_
	places to evaluate an interpolant
double *	y_interp_
	values and derivatives of the interpolant at x_interp_
double *	dy_interp_
double *	d2y_interp_
double *	y_ref_
	reference values and derivatives
double *	dy_ref_
double *	d2y_ref_
const double	tol_ [3] = {1e-14, 1e-13, 1e-12}
	y/dy/d2y tolerance for cross-check
std::vector< std::vector< std::function< double(double)> > >	f_
	Sample functions & derivatives in error bound check.

Detailed Description

Unit test of class CubicSpline.

Tested functions include:

• build Constructs a cubic spline interpolant from a set of data points and boundary conditions.
• eval Evaluates a single interpolant at multiple places.
• add Adds an interpolant that shares the same knots.
• multi_eval Evaluates multiple interpolants at a single place.
• reserve Reserves memory for multiple interpolants.
• heap_usage Returns the heap usage of the object.
• xmin, xmax Returns the first and last knots.

Constructor & Destructor Documentation

CubicSplineTest()

CubicSplineTest::CubicSplineTest ( )

protected

~CubicSplineTest()

CubicSplineTest::~CubicSplineTest ( )

protecteddefault

Member Function Documentation

error_bound()

double CubicSplineTest::error_bound ( int  n, const double *  x, const std::function< double(double)> &  f, int  d = 0  ) const

protected

theoretical error bound for complete cubic spline

read()

void CubicSplineTest::read ( const std::string &  fname, int &  n, double *  x, double *  y, BoundaryCondition &  bc_start, BoundaryCondition &  bc_end, int &  n_interp, double *  x_interp, double *  y_interp, double *  dy_interp, double *  d2y_interp  ) const

protected

Member Data Documentation

d2y_interp_

double* CubicSplineTest::d2y_interp_

protected

d2y_ref_

double* CubicSplineTest::d2y_ref_

protected

dy_

double* CubicSplineTest::dy_

protected

derivatives at knots (computed when building a cubic spline)

dy_interp_

double* CubicSplineTest::dy_interp_

protected

dy_ref_

double* CubicSplineTest::dy_ref_

protected

f_

std::vector<std::vector<std::function<double(double)> > > CubicSplineTest::f_

protected

Sample functions & derivatives in error bound check.

Note

Functions with vanishing 4-th derivative in an interval should in principle be interpolated exactly by a cubic spline. However, the presence of floating-point rounding errors would lead to some discrepancy between the interpolant and the original function. Such error is not covered by the error bound formula. Functions here should not include those kind of functions.

interp_

std::vector<double> CubicSplineTest::interp_

protected

buffer for interpolant evaluation

n_interp_max_

int CubicSplineTest::n_interp_max_

protected

maximum number of places to evaluate an interpolant

n_max_

int CubicSplineTest::n_max_

protected

maximum number of knots

spline_

std::vector<double> CubicSplineTest::spline_

protected

buffer for a cubic spline (x_, y_ & dy_)

tol_

const double CubicSplineTest::tol_[3] = {1e-14, 1e-13, 1e-12}

protected

y/dy/d2y tolerance for cross-check

x_

double* CubicSplineTest::x_

protected

knots (x-coordinates of data points)

x_interp_

double* CubicSplineTest::x_interp_

protected

places to evaluate an interpolant

y_

double* CubicSplineTest::y_

protected

values at knots (y-coordinates of data points)

y_interp_

double* CubicSplineTest::y_interp_

protected

values and derivatives of the interpolant at x_interp_

y_ref_

double* CubicSplineTest::y_ref_

protected

reference values and derivatives

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

• /home/runner/work/abacus-develop/abacus-develop/source/source_base/test/cubic_spline_test.cpp