/* nag_interp_dim1_monotonic_eval (e01bfc) Example Program.
*
* Copyright 2021 Numerical Algorithms Group
*
* Mark 27.3, 2021.
*/
#include <nag.h>
#include <stdio.h>
int main(void) {
Integer exit_status = 0, i, m, n, r;
NagError fail;
double *d = 0, *f = 0, *pf = 0, *px = 0, step, *x = 0;
INIT_FAIL(fail);
printf("nag_interp_dim1_monotonic_eval (e01bfc) Example Program Results\n");
scanf("%*[^\n]"); /* Skip to end of line */
scanf("%" NAG_IFMT "", &n);
if (n >= 2) {
if (!(d = NAG_ALLOC(n, double)) || !(f = NAG_ALLOC(n, double)) ||
!(x = NAG_ALLOC(n, double))) {
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
} else {
printf("Invalid n.\n");
exit_status = 1;
return exit_status;
}
for (r = 0; r < n; r++)
scanf("%lf%lf%lf", &x[r], &f[r], &d[r]);
scanf("%" NAG_IFMT "", &m);
if (m >= 1) {
if (!(pf = NAG_ALLOC(m, double)) || !(px = NAG_ALLOC(m, double))) {
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
} else {
printf("Invalid m.\n");
exit_status = 1;
return exit_status;
}
/* Compute M Equally spaced points from x[0] to x[n-1]. */
step = (x[n - 1] - x[0]) / (double)(m - 1);
for (i = 0; i < m; i++)
px[i] = MIN(x[0] + i * step, x[n - 1]);
/* nag_interp_dim1_monotonic_eval (e01bfc).
* Evaluation of interpolant computed by
* nag_interp_dim1_monotonic (e01bec), function only
*/
nag_interp_dim1_monotonic_eval(n, x, f, d, m, px, pf, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_interp_dim1_monotonic_eval (e01bfc).\n%s\n",
fail.message);
exit_status = 1;
goto END;
}
printf(" Interpolated\n");
printf(" Abscissa Value\n");
for (i = 0; i < m; i++)
printf("%13.4f%13.4f\n", px[i], pf[i]);
END:
NAG_FREE(d);
NAG_FREE(f);
NAG_FREE(pf);
NAG_FREE(px);
NAG_FREE(x);
return exit_status;
}