C Library Functions - splint (3)
NAME
splint(3f) - [M_math:fit] interpolates and twice differentiates a cubic spline
CONTENTS
Synopsis
Description
Options
Returns
Example
Pedigree
SYNOPSIS
subroutine splint (x,y,ypp,n,xi,yi,ypi,yppi,ni,kerr)
integer,intent(in) :: n, ni real,intent(in) :: x(n),y(n),ypp(n),xi(ni) real,intent(out) :: yi(ni),ypi(ni),yppi(ni)
DESCRIPTION
SPLINT(3f) interpolates and twice differentiates a cubic spline defined by X, Y, and YPP at the abscissas in XI. The spline may have been determined by SPLIFT(3f) or SMOOTH(3f) or any other spline fitting routine which provides second derivatives.
OPTIONS
X array of data abscissas Y array of data ordinates YPP array of spline second derivatives N number of data points (the dimension of X,Y, and YPP) XI array of abscissas (in arbitrary order) at which the spline is to be interpolated. NI dimension of XI, YI, YPI, and YPPI. (if NI=1, XI, YI, YPI and YPPI may be simple variables.)
RETURNS
YI array of interpolated ordinates (OUTPUT) YPI array of interpolated derivatives (OUTPUT) YPPI array of interpolated second derivatives (OUTPUT) KERR error status parameter (OUTPUT)
NORMAL CODES
=0 means the spline was evaluated at each abscissa in XI using only interpolation. =1 means the spline was evaluated at each abscissa in XI, but at least one extrapolation was performed.
ABNORMAL CODE
=2 means the requested number of interpolations, NI, was not positive.
EXAMPLE
PEDIGREE
Original written by:
Rondall E. Jones Sandia Mathematical Program Library Applied Mathematics Division 2642 Sandia Laboratories P. O. Box 5800 Albuquerque, New Mexico 87115Control Data 6600 Version 5.1, 10 December 1973
| Nemo Release 3.1 | splint (3) | February 23, 2025 |
