#include <math.h>
#include "../../Exceptions/error.h"
Go to the source code of this file.
Functions | |
void | spline (double *x, double *y, int n, double yp1, double ypn, double *y2) |
Spline interpolation - calculation of an array with second derivatives (called only once for each interpolation of an array). | |
void | splint (double *xa, double *ya, double *y2a, int n, double x, double *y) |
Spline interpolation. |
Definition in file spline.cpp.
void spline | ( | double * | x, | |
double * | y, | |||
int | n, | |||
double | yp1, | |||
double | ypn, | |||
double * | y2 | |||
) |
Spline interpolation - calculation of an array with second derivatives (called only once for each interpolation of an array).
Given arrays x[1..n] and y[1..n] containing a tabulated function, i.e., yi = f (xi ), with x1 < x2 < . . . < xN , and given values yp1 and ypn for the first derivative of the interpolating function at points 1 and n, respectively, this routine returns an array y2[1..n] that contains the second derivatives of the interpolating function at the tabulated points xi . If yp1 and/or ypn are equal to 1 - 10^30 or larger, the routine is signaled to set the corresponding boundary condition for a natural spline, with zero second derivative on that boundary.
*x | - old x | |
*y | - old function | |
n | - number of points | |
yp1 | - derivative on boundary / flag if > 10^30 | |
ypn | - derivative on boundary / flag if > 10^30 | |
*y2 | - array with second derivatives of the function |
Definition at line 30 of file spline.cpp.
References i.
Referenced by Matrix1D< T >::Spline().
void splint | ( | double * | xa, | |
double * | ya, | |||
double * | y2a, | |||
int | n, | |||
double | x, | |||
double * | y | |||
) |
Spline interpolation.
Given the arrays xa[1..n] and ya[1..n], which tabulate a function (with the xai -s in order), and given the array y2a[1..n], which is the output from spline above, and given a value of x, this routine returns a cubic-spline interpolated value y.
*xa | - old grid array | |
*ya | - old function array | |
*y2a | - old function second derivatives array | |
n | - size of arrays | |
x | - new grid point | |
*y | - new grid value |
Definition at line 86 of file spline.cpp.
References nrerror().
Referenced by Matrix1D< T >::Spline().