NAG Library Manual, Mark 28.5
```/* nag_quad_dim1_fin_osc_fn (d01rkc) Example Program.
*
* Copyright 2022 Numerical Algorithms Group.
*
* Mark 28.5, 2022.
*/
#include <math.h>
#include <nag.h>
#include <stdio.h>

#ifdef __cplusplus
extern "C" {
#endif
static void NAG_CALL f(const double x[], Integer nx, double fv[],
Integer *iflag, Nag_Comm *comm);
#ifdef __cplusplus
}
#endif

int main(void) {
Integer exit_status = 0;
double a, b, result, epsabs, epsrel, abserr, pi;
Integer key, lrinfo, liinfo, maxsub;
Integer *iinfo = 0;
double *rinfo = 0;

/* Nag Types */
NagError fail;
Nag_Comm comm;

INIT_FAIL(fail);

key = 6;
pi = nag_math_pi;
epsabs = 0.0;
epsrel = 1.0e-04;
a = 0.0;
b = 2.0 * pi;
maxsub = 20;
lrinfo = 4 * maxsub;
liinfo = MAX(maxsub, 4);

/* Allocate memory */
if (!(rinfo = NAG_ALLOC(lrinfo, double)) ||
!(iinfo = NAG_ALLOC(liinfo, Integer))) {
printf("Allocation failure\n");
exit_status = -1;
goto END;
}

printf("a        -     lower limit of integration = %11.4f\n", a);
printf("b        -     upper limit of integration = %11.4f\n", b);
printf("epsabs   -    absolute accuracy requested = %11.2e\n", epsabs);
printf("epsrel   -    relative accuracy requested = %11.2e\n", epsrel);
printf("maxsub   - maximum number of subintervals = %11" NAG_IFMT "\n",
maxsub);
printf("\n");

/* Evaluate the integral using the vectorized One-dimensional adaptive
*/
nag_quad_dim1_fin_osc_fn(f, key, a, b, epsabs, epsrel, maxsub, &result,
&abserr, rinfo, iinfo, &comm, &fail);
if (fail.code != NE_NOERROR)
printf("Error or warning from nag_quad_dim1_fin_osc_fn (d01rkc) %s\n",
fail.message);
if (fail.code != NE_INT_ARG_LT && fail.code != NE_ALLOC_FAIL &&
fail.code != NE_NO_LICENCE && fail.code != NE_USER_STOP) {
printf("result   -  approximation to the integral = %11.4f\n", result);
printf("abserr   - estimate of the absolute error = %11.2e\n", abserr);
printf("iinfo(0) -    number of subintervals used = %11" NAG_IFMT "\n",
iinfo[0]);
} else if (fail.code == NE_USER_STOP) {
printf("Exit requested from f\n");
} else {
exit_status = 1;
goto END;
}

END:

NAG_FREE(rinfo);
NAG_FREE(iinfo);

return exit_status;
}

static void NAG_CALL f(const double x[], Integer nx, double fv[],
Integer *iflag, Nag_Comm *comm) {
Integer i;

/* Set iflag negative to terminate execution for any reason. */
*iflag = 0;

for (i = 0; i < nx; i++)
fv[i] = x[i] * (sin(30.0 * x[i])) * cos(x[i]);
}
```