```/* nag_zggevx (f08wpc) Example Program.
*
* NAGPRODCODE Version.
*
* Copyright 2016 Numerical Algorithms Group.
*
* Mark 26, 2016.
*/

#include <stdio.h>
#include <math.h>
#include <nag.h>
#include <nag_stdlib.h>
#include <naga02.h>
#include <nagf08.h>
#include <nagx02.h>

int main(void)
{
/* Scalars */
Complex z;
double abnorm, abnrm, bbnrm, eps, small, tol;
Integer i, ihi, ilo, j, n, pda, pdb, pdvl, pdvr;
Integer exit_status = 0;

/* Arrays */
Complex *a = 0, *alpha = 0, *b = 0, *beta = 0, *vl = 0, *vr = 0;
double *lscale = 0, *rconde = 0, *rcondv = 0, *rscale = 0;
char nag_enum_arg[40];

/* Nag Types */
NagError fail;
Nag_OrderType order;
Nag_LeftVecsType jobvl;
Nag_RightVecsType jobvr;
Nag_RCondType sense;

#ifdef NAG_COLUMN_MAJOR
#define A(I, J)  a[(J-1)*pda + I - 1]
#define B(I, J)  b[(J-1)*pdb + I - 1]
order = Nag_ColMajor;
#else
#define A(I, J)  a[(I-1)*pda + J - 1]
#define B(I, J)  b[(I-1)*pdb + J - 1]
order = Nag_RowMajor;
#endif

INIT_FAIL(fail);

printf("nag_zggevx (f08wpc) Example Program Results\n");

/* Skip heading in data file */
scanf("%*[^\n]");
scanf("%" NAG_IFMT "%*[^\n]", &n);
if (n < 0) {
printf("Invalid n\n");
exit_status = 1;
goto END;
}
scanf(" %39s%*[^\n]", nag_enum_arg);
/* nag_enum_name_to_value (x04nac).
* Converts NAG enum member name to value
*/
jobvl = (Nag_LeftVecsType) nag_enum_name_to_value(nag_enum_arg);
scanf(" %39s%*[^\n]", nag_enum_arg);
jobvr = (Nag_RightVecsType) nag_enum_name_to_value(nag_enum_arg);
scanf(" %39s%*[^\n]", nag_enum_arg);
sense = (Nag_RCondType) nag_enum_name_to_value(nag_enum_arg);

pda = n;
pdb = n;
pdvl = (jobvl == Nag_LeftVecs ? n : 1);
pdvr = (jobvr == Nag_RightVecs ? n : 1);

/* Allocate memory */
if (!(a = NAG_ALLOC(n * n, Complex)) ||
!(b = NAG_ALLOC(n * n, Complex)) ||
!(alpha = NAG_ALLOC(n, Complex)) ||
!(beta = NAG_ALLOC(n, Complex)) ||
!(vl = NAG_ALLOC(pdvl * pdvl, Complex)) ||
!(vr = NAG_ALLOC(pdvr * pdvr, Complex)) ||
!(lscale = NAG_ALLOC(n, double)) ||
!(rconde = NAG_ALLOC(n, double)) ||
!(rcondv = NAG_ALLOC(n, double)) || !(rscale = NAG_ALLOC(n, double)))
{
printf("Allocation failure\n");
exit_status = -1;
goto END;
}

/* Read in the matrices A and B */
for (i = 1; i <= n; ++i)
for (j = 1; j <= n; ++j)
scanf(" ( %lf , %lf )", &A(i, j).re, &A(i, j).im);
scanf("%*[^\n]");
for (i = 1; i <= n; ++i)
for (j = 1; j <= n; ++j)
scanf(" ( %lf , %lf )", &B(i, j).re, &B(i, j).im);
scanf("%*[^\n]");

/* Solve the generalized eigenvalue problem using nag_zggevx (f08wpc). */
nag_zggevx(order, Nag_BalanceBoth, jobvl, jobvr, sense, n, a, pda, b, pdb,
alpha, beta, vl, pdvl, vr, pdvr, &ilo, &ihi, lscale, rscale,
&abnrm, &bbnrm, rconde, rcondv, &fail);
if (fail.code != NE_NOERROR) {
printf("Error from nag_zggevx (f08wpc).\n%s\n", fail.message);
exit_status = 1;
goto END;
}

/* nag_real_safe_small_number (x02amc), nag_machine_precision (x02ajc) */
eps = nag_machine_precision;
small = nag_real_safe_small_number;
if (abnrm == 0.0)
abnorm = ABS(bbnrm);
else if (bbnrm == 0.0)
abnorm = ABS(abnrm);
else if (ABS(abnrm) >= ABS(bbnrm))
abnorm = ABS(abnrm) * sqrt(1.0 + (bbnrm / abnrm) * (bbnrm / abnrm));
else
abnorm = ABS(bbnrm) * sqrt(1.0 + (abnrm / bbnrm) * (abnrm / bbnrm));

tol = eps * abnorm;

/* Print out eigenvalues and associated condition number and bounds */
if (sense != Nag_NotRCond)
printf("\n R = Reciprocal condition number, E = Error bound\n\n");
printf("%22s", "Eigenvalues");
if (sense == Nag_RCondEigVals || sense == Nag_RCondBoth)
printf("%15s%10s", "R", "E");
printf("\n");
for (j = 0; j < n; ++j) {
/* Print out information on the j-th eigenvalue */
if (nag_complex_abs(alpha[j]) * small >= nag_complex_abs(beta[j])) {
printf("%2" NAG_IFMT " is numerically infinite or undetermined\n",
j + 1);
printf("   alpha = (%9.4f, %9.4f), beta = (%9.4f, %9.4f)\n",
alpha[j].re, alpha[j].im, beta[j].re, beta[j].im);
}
else {
z = nag_complex_divide(alpha[j], beta[j]);
printf("%2" NAG_IFMT " (%13.4e, %13.4e)", j + 1, z.re, z.im);
if (sense == Nag_RCondEigVals || sense == Nag_RCondBoth) {
printf(" %10.1e", rconde[j]);
if (rconde[j] > 0.0)
printf(" %9.1e", tol / rconde[j]);
else
printf(" infinite");
}
printf("\n");
}
}

/* Print out information on the eigenvectors as requested */
if (jobvl == Nag_LeftVecs) {
printf("\n");
/* Print left eigenvectors using nag_gen_complx_mat_print (x04dac). */
fflush(stdout);
nag_gen_complx_mat_print(order, Nag_GeneralMatrix, Nag_NonUnitDiag, n,
n, vl, pdvl, "    Left eigenvectors (columns)",
0, &fail);
}
if (jobvr == Nag_RightVecs && fail.code == NE_NOERROR) {
printf("\n");
/* Print rightt eigenvectors using nag_gen_complx_mat_print (x04dac). */
fflush(stdout);
nag_gen_complx_mat_print(order, Nag_GeneralMatrix, Nag_NonUnitDiag, n,
n, vr, pdvr, "    Right eigenvectors (columns)",
0, &fail);
}
if (fail.code != NE_NOERROR) {
printf("Error from nag_gen_complx_mat_print (x04dac).\n%s\n",
fail.message);
exit_status = 1;
goto END;
}
if (sense == Nag_RCondEigVecs || sense == Nag_RCondBoth) {
printf("%2s", "R");
for (j = 0; j < n; ++j)
printf(" %8.1e", rcondv[j]);
printf("\n%2s", "E");
for (j = 0; j < n; ++j) {
if (rcondv[j] > 0.0)
printf(" %8.1e", tol / rcondv[j]);
else
printf(" infinite");
}
printf("\n");
}

END:
NAG_FREE(a);
NAG_FREE(b);
NAG_FREE(alpha);
NAG_FREE(beta);
NAG_FREE(vl);
NAG_FREE(vr);
NAG_FREE(lscale);
NAG_FREE(rconde);
NAG_FREE(rcondv);
NAG_FREE(rscale);

return exit_status;
}
```