2.8.29 spline

1 Brief Information
2 Command Line Usage
3 X-Function Execution Options
4 Variables
5 Description
6 Examples
7 Algorithm
8 Related X-Functions

Brief Information

Perform cubic spline interpolation/extrapolation of XY data

Command Line Usage

1. spline ix:=Col(3) iy:=(Col(1), Col(2));

2. spline ix:=Col(3) iy:=Col(2) ox:=Col(4);

X-Function Execution Options

Please refer to the page for additional option switches when accessing the x-function from script

Variables

Display Name	Variable Name	I/O and Type	Default Value	Description
X Values to Interpolate	ix	Input vector	<unassigned>	Specifies the X values to be interpolated on the spline
Input	iy	Input XYRange	<active>	The input XY range data to be interpolated
Boundary	boundary	Input int	notaknot	Boundary condition only available in cubic spline method Option list: natural:Natural 2nd derivatives are 0 on both end notaknot:Not-A-Knot 3rd derivatives are continuous on the second and last-second point
Result of Interpolation	ox	Output vector	<new>	Specifies the column to save output interpolated Y values on the spline
Coefficients	coef	Output vector	<optional>	Whether or not to output spline coefficients

Description

This function performs Cubic spline interpolation on XY range data. You should specify the X coordinates on the spline, and it will output a vector contains the interpolated values on these X values.

Examples

Import Interpolation.dat on \Samples\Mathematics folder.
Highlight column B and type spline -d on the command window to bring up the dialog.
On the X Value to Interpolate drop-down list, select Col(C).
Click OK to do interpolation on column C values.