Interpolation and Approximation

Routines

Curve and Surface Fitting with Splines

Returns the derived type array result SPLINE_CONSTRAINTS

Returns an array result, given an array of input SPLINE_VALUES

Weighted least-squares fitting by B-splines to discrete One-Dimensional data is performed SPLINE_FITTING

Returns the derived type array result given optional input SURFACE_CONSTRAINTS

Returns a tensor product array result, given two arrays of independent variable values SURFACE_VALUES

Weighted least-squares fitting by tensor product B-splines to discrete two-dimensional data is performed SURFACE_FITTING

Cubic Spline Interpolation

Easy to use cubic spline routine CSIEZ

Not-a-knot CSINT

Derivative end conditions CSDEC

Hermite CSHER

Akima CSAKM

Shape preserving CSCON

Periodic CSPER

Cubic Spline Evaluation and Integration

Evaluation CSVAL

Evaluation of the derivative CSDER

Evaluation on a grid CS1GD

Integration CSITG

B-spline Interpolation

Easy to use spline routine SPLEZ

One-dimensional interpolation BSINT

Knot sequence given interpolation data BSNAK

Optimal knot sequence given interpolation data BSOPK

Two-dimensional tensor product interpolation BS2IN

Three-dimensional tensor product interpolation BS3IN

Spline Evaluation, Integration, and Conversion to Piecewise Polynomial Given the B-spline Representation

Evaluation BSVAL

Evaluation of the derivative BSDER

Evaluation on a grid BS1GD

One-dimensional integration BSITG

Two-dimensional evaluation BS2VL

Two-dimensional evaluation of the derivative BS2DR

Two-dimensional evaluation on a grid BS2GD

Two-dimensional integration BS2IG

Three-dimensional evaluation BS3VL

Three-dimensional evaluation of the derivative BS3DR

Three-dimensional evaluation on a grid BS3GD

Three-dimensional integration BS3IG

Convert B-spline representation to piecewise polynomial BSCPP

Piecewise Polynomial

Evaluation PPVAL

Evaluation of the derivative PPDER

Evaluation on a grid PP1GD

Integration PPITG

Quadratic Polynomial Interpolation Routines for Gridded Data

One-dimensional evaluation QDVAL

One-dimensional evaluation of the derivative QDDER

Two-dimensional evaluation QD2VL

Two-dimensional evaluation of the derivative QD2DR

Three-dimensional evaluation QD3VL

Three-dimensional evaluation of the derivative QD3DR

Multi-dimensional Interpolation

Akima’s surface fitting method SURF

Multidimensional interpolation and differentiation SURFND

Least-Squares Approximation

Linear polynomial RLINE

General polynomial RCURV

General functions FNLSQ

Splines with fixed knots BSLSQ

Splines with variable knot BSVLS

Splines with linear constraints CONFT

Two-dimensional tensor-product splines with fixed knots BSLS2

Three-dimensional tensor-product splines with fixed knots BSLS3

Cubic Spline Smoothing

Smoothing by error detection CSSED

Smoothing spline CSSMH

Smoothing spline using cross-validation CSSCV

Rational L∞Approximation

Rational Chebyshev RATCH