```/* nag_sparse_herm_chol_fac (f11jnc) Example Program.
*
* Copyright 2014 Numerical Algorithms Group.
*
* Mark 23, 2011.
*/

#include <nag.h>
#include <nag_stdlib.h>
#include <naga02.h>
#include <nagf11.h>

int main(void)
{
/* Scalars */
Integer             exit_status = 0;
double              dscale, dtol;
Integer             i, la, lfill, n, nnz, nnzc, npivm;
/* Arrays */
Complex             *a = 0;
Integer             *icol = 0, *ipiv = 0, *irow = 0, *istr = 0;
char                nag_enum_arg[100];
/* NAG types */
Nag_SparseSym_Piv   pstrat;
Nag_SparseSym_Fact  mic;
NagError            fail;

INIT_FAIL(fail);

printf("nag_sparse_herm_chol_fac (f11jnc) Example Program Results\n");
/* Skip heading in data file*/
scanf("%*[^\n]");
scanf("%ld%*[^\n]%ld%*[^\n]", &n, &nnz);

/* Allocate memory */
la = 3 * nnz;
if (
!(a = NAG_ALLOC(la, Complex)) ||
!(icol = NAG_ALLOC(la, Integer)) ||
!(ipiv = NAG_ALLOC(n, Integer)) ||
!(irow = NAG_ALLOC(la, Integer)) ||
!(istr = NAG_ALLOC(n + 1, Integer))
)
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}
scanf("%ld%lf%*[^\n]", &lfill, &dtol);
scanf("%99s%*[^\n]", nag_enum_arg);
/* nag_enum_name_to_value (x04nac).
* Converts NAG enum member name to value
*/
mic = (Nag_SparseSym_Fact) nag_enum_name_to_value(nag_enum_arg);
scanf("%lf%*[^\n]", &dscale);
scanf("%99s%*[^\n]", nag_enum_arg);
pstrat = (Nag_SparseNsym_Piv) nag_enum_name_to_value(nag_enum_arg);

/* Read the matrix a */
for (i = 0; i < nnz; i++)
scanf(" ( %lf , %lf ) %ld%ld%*[^\n] ",
&a[i].re, &a[i].im, &irow[i], &icol[i]);

/* Calculate incomplete Cholesky factorization using
* nag_sparse_herm_chol_fac (f11jnc).
*/
nag_sparse_herm_chol_fac(n, nnz, a, la, irow, icol, lfill, dtol, mic, dscale,
pstrat, ipiv, istr, &nnzc, &npivm, &fail);
if (fail.code != NE_NOERROR)
{
printf("Error from nag_sparse_herm_chol_fac (f11jnc).\n%s\n",
fail.message);
exit_status = 1;
goto END;
}

/* Output original matrix*/
printf(" Original Matrix \n");
printf("  n = %4ld, nnz  = %4ld\n", n, nnz);
printf("%8s%16s%23s%9s\n","i","a[i]","irow[i]","icol[i]");
for (i = 0; i < nnz; i++)
printf("%8ld (%13.4e, %13.4e) %8ld %8ld \n",
i, a[i].re, a[i].im, irow[i], icol[i]);
printf("\n");

/* Output details of the factorization*/
printf(" Factorization \n");
printf("  n = %4ld, nnzc = %4ld, npivm = %4ld\n",
n, nnzc, npivm);
printf("%8s%16s%23s%9s\n","i","a[i]","irow[i]","icol[i]");
for (i = nnz; i < nnz + nnzc; i++)
printf("%8ld (%13.4e, %13.4e) %8ld %8ld \n",
i , a[i].re, a[i].im, irow[i], icol[i]);
printf("\n%8s%12s\n","i","ipiv[i-1]");
for (i = 1; i <= n; i++)
printf("%8ld%8ld\n", i, ipiv[i-1]);

END:
NAG_FREE(a);
NAG_FREE(icol);
NAG_FREE(ipiv);
NAG_FREE(irow);
NAG_FREE(istr);
return exit_status;
}
```