Interpolator Namespace Reference

Detailed Description

1D interpolation using GSL splines.

Wraps the GSL interpolation library (https://www.gnu.org/software/gsl/doc/html/interp.html). Provides a stateful Interp class and a convenience interpolate() function. Several interpolation methods are available via Method. Does not extrapolate: values outside [xmin, xmax] are returned as zero.

Classes
class	Interp
	Stateful 1D interpolation object using GSL. More...

Enumerations
enum class	Method {   linear , polynomial , cspline , cspline_periodic ,   akima , akima_periodic , steffen }
	Interpolation method. More...

Functions
std::vector< double >	interpolate (const std::vector< double > &x_in, const std::vector< double > &y_in, const std::vector< double > &x_out, Method method=Method::cspline)
	Convenience wrapper: interpolates y_in(x_in) and evaluates at x_out.

Enumeration Type Documentation

Method

enum class Interpolator::Method

strong

Interpolation method.

See https://www.gnu.org/software/gsl/doc/html/interp.html for full details.

Enumerator
linear	Linear interpolation; no additional memory required.
polynomial	Polynomial interpolation; only suitable for small numbers of points.
cspline	Cubic spline with natural boundary conditions (zero second derivative at endpoints)
cspline_periodic	Cubic spline with periodic boundary conditions; first and last y-values must match.
akima	Akima spline with natural boundary conditions (Wodicka non-rounded corner algorithm)
akima_periodic	Akima spline with periodic boundary conditions.
steffen	Steffen's monotone spline: no spurious oscillations between data points. GSL v2+ only.

Function Documentation

interpolate()

std::vector< double > Interpolator::interpolate ( const std::vector< double > &  x_in, const std::vector< double > &  y_in, const std::vector< double > &  x_out, Method  method = Method::cspline  )

inline

Convenience wrapper: interpolates y_in(x_in) and evaluates at x_out.

Parameters

x_in	Input x values (strictly increasing).
y_in	Input y values; must satisfy y_in.size() == x_in.size().
x_out	Points at which to evaluate the interpolant.
method	Interpolation method (default: cspline).

Returns

Vector of interpolated values at each point in x_out.