/* nag_inteq_abel_weak_weights (d05byc) Example Program.
 *
 * Copyright 2024 Numerical Algorithms Group.
 *
 * Mark 30.1, 2024.
 */
#include <math.h>
#include <nag.h>
int main(void) {
  /* Scalars */
  Integer exit_status = 0;
  Integer i, iorder, iq, j, lomega, n, ncols, ncwt, nmax;
  /* Arrays */
  double *omega = 0, *sw = 0;
  /* NAG types */
  NagError fail;

  INIT_FAIL(fail);

  printf("nag_inteq_abel_weak_weights (d05byc) Example Program Results\n");

  /* Skip heading in data file */
  scanf("%*[^\n] ");
  scanf("%" NAG_IFMT "%*[^\n] ", &iorder);
  scanf("%" NAG_IFMT "%*[^\n] ", &iq);

  ncwt = pow(2, iq + 1);
  lomega = 2 * ncwt;
  ncols = 2 * iorder - 1;
  nmax = ncwt + ncols;

  if (!(omega = NAG_ALLOC(lomega, double)) ||
      !(sw = NAG_ALLOC(ncols * nmax, double))) {
    printf("Allocation failure\n");
    exit_status = -1;
    goto END;
  }

  /*
     nag_inteq_abel_weak_weights (d05byc).
     Generate weights for use in solving weakly singular Abel-type equations.
   */
  nag_inteq_abel_weak_weights(iorder, iq, omega, sw, &fail);

  if (fail.code != NE_NOERROR) {
    printf("Error from nag_inteq_abel_weak_weights (d05byc).\n%s\n",
           fail.message);
    exit_status = 1;
    goto END;
  }

  printf("\nFractional convolution weights\n\n");
  for (i = 0; i < ncwt; i++)
    printf("%5" NAG_IFMT " %9.4f\n", i, omega[i]);

  printf("\nFractional starting weights W\n\n");

#define SW(I, J) sw[J * nmax + I - 1]

  for (n = 1; n <= nmax; n++) {
    printf("%5" NAG_IFMT " ", n);
    for (j = 0; j < ncols; j++)
      printf("%9.4f", SW(n, j));
    printf("\n");
  }

#undef SW

END:

  NAG_FREE(sw);
  NAG_FREE(omega);

  return exit_status;
}