/* nag_quad_dim1_gauss_wgen (d01tcc) Example Program.
*
* Copyright 2022 Numerical Algorithms Group.
*
* Mark 28.6, 2022.
*/
#include <nag.h>
#include <stdio.h>
int main(void) {
Integer exit_status = 0;
Integer i, n;
double a, b, c, d;
Nag_QuadType quadtype;
double *abscis = 0, *weight = 0;
/* Nag Types */
NagError fail;
INIT_FAIL(fail);
printf("nag_quad_dim1_gauss_wgen (d01tcc) Example Program Results\n");
/* Skip heading in data file */
scanf("%*[^\n] ");
/* Input a, b, c, d and n */
scanf("%lf %lf %lf %lf", &a, &b, &c, &d);
scanf("%" NAG_IFMT "%*[^\n] ", &n);
quadtype = Nag_Quad_Gauss_Laguerre_Adjusted;
if (!(abscis = NAG_ALLOC(n, double)) || !(weight = NAG_ALLOC(n, double))) {
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
/* nag_quad_dim1_gauss_wgen (d01tcc).
* Calculation of weights and abscissae for
* Gaussian quadrature rules, general choice of rule.
*/
nag_quad_dim1_gauss_wgen(quadtype, a, b, c, d, n, weight, abscis, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_quad_dim1_gauss_wgen (d01tcc).\n%s\n", fail.message);
exit_status = 1;
goto END;
}
printf("\nLaguerre formula, %3" NAG_IFMT " points\n\n"
" Abscissae Weights\n\n",
n);
for (i = 0; i < n; i++) {
printf("%15.5e", abscis[i]);
printf("%15.5e\n", weight[i]);
}
printf("\n");
END:
NAG_FREE(abscis);
NAG_FREE(weight);
return exit_status;
}