/* nag_fit_dim1_spline_integ (e02bdc) Example Program.
*
* Copyright 2024 Numerical Algorithms Group.
*
* Mark 30.0, 2024.
*/
#include <nag.h>
#include <stdio.h>
int main(void) {
Integer exit_status = 0, j;
NagError fail;
Nag_Spline spline;
double integral;
INIT_FAIL(fail);
/* Initialize spline */
spline.lamda = 0;
spline.c = 0;
printf("nag_fit_dim1_spline_integ (e02bdc) Example Program Results\n");
scanf("%*[^\n]"); /* Skip heading in data file */
while (scanf("%" NAG_IFMT "", &(spline.n)) != EOF)
{
if (spline.n > 0) {
if (!(spline.c = NAG_ALLOC(spline.n, double)) ||
!(spline.lamda = NAG_ALLOC(spline.n, double))) {
printf("Storage allocation failed. Reduce the "
"size of spline.n\n");
exit_status = 1;
goto END;
}
} else {
printf("spline.n is out of range : spline.n = %" NAG_IFMT "\n", spline.n);
exit_status = 1;
goto END;
}
for (j = 0; j < spline.n; j++)
scanf("%lf", &(spline.lamda[j]));
for (j = 0; j < spline.n - 3; j++)
scanf("%lf", &(spline.c[j]));
/* nag_fit_dim1_spline_integ (e02bdc).
* Evaluation of fitted cubic spline, definite integral
*/
nag_fit_dim1_spline_integ(&spline, &integral, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_fit_dim1_spline_integ (e02bdc).\n%s\n",
fail.message);
exit_status = 1;
goto END;
}
printf("Definite integral = %12.3e\n", integral);
NAG_FREE(spline.c);
NAG_FREE(spline.lamda);
}
END:
return exit_status;
}