text: #include <math.h>
  #include <stdlib.h>
  #include <string.h>
  #include <stdio.h>
  #include <complex.h>
  #ifdef complex
  #undef complex
  #endif
  #ifdef I
  #undef I
  #endif
  
  #if defined(_WIN64)
  typedef long long BLASLONG;
  typedef unsigned long long BLASULONG;
  #else
  typedef long BLASLONG;
  typedef unsigned long BLASULONG;
  #endif
  
  #ifdef LAPACK_ILP64
  typedef BLASLONG blasint;
  #if defined(_WIN64)
  #define blasabs(x) llabs(x)
  #else
  #define blasabs(x) labs(x)
  #endif
  #else
  typedef int blasint;
  #define blasabs(x) abs(x)
  #endif
  
  typedef blasint integer;
  
  typedef unsigned int uinteger;
  typedef char *address;
  typedef short int shortint;
  typedef float real;
  typedef double doublereal;
  typedef struct { real r, i; } complex;
  typedef struct { doublereal r, i; } doublecomplex;
  #ifdef _MSC_VER
  static inline _Fcomplex Cf(complex *z) {_Fcomplex zz={z->r , z->i}; return zz;}
  static inline _Dcomplex Cd(doublecomplex *z) {_Dcomplex zz={z->r , z->i};return zz;}
  static inline _Fcomplex * _pCf(complex *z) {return (_Fcomplex*)z;}
  static inline _Dcomplex * _pCd(doublecomplex *z) {return (_Dcomplex*)z;}
  #else
  static inline _Complex float Cf(complex *z) {return z->r + z->i*_Complex_I;}
  static inline _Complex double Cd(doublecomplex *z) {return z->r + z->i*_Complex_I;}
  static inline _Complex float * _pCf(complex *z) {return (_Complex float*)z;}
  static inline _Complex double * _pCd(doublecomplex *z) {return (_Complex double*)z;}
  #endif
  #define pCf(z) (*_pCf(z))
  #define pCd(z) (*_pCd(z))
  typedef int logical;
  typedef short int shortlogical;
  typedef char logical1;
  typedef char integer1;
  
  #define TRUE_ (1)
  #define FALSE_ (0)
  
  /* Extern is for use with -E */
  #ifndef Extern
  #define Extern extern
  #endif
  
  /* I/O stuff */
  
  typedef int flag;
  typedef int ftnlen;
  typedef int ftnint;
  
  /*external read, write*/
  typedef struct
  {	flag cierr;
  	ftnint ciunit;
  	flag ciend;
  	char *cifmt;
  	ftnint cirec;
  } cilist;
  
  /*internal read, write*/
  typedef struct
  {	flag icierr;
  	char *iciunit;
  	flag iciend;
  	char *icifmt;
  	ftnint icirlen;
  	ftnint icirnum;
  } icilist;
  
  /*open*/
  typedef struct
  {	flag oerr;
  	ftnint ounit;
  	char *ofnm;
  	ftnlen ofnmlen;
  	char *osta;
  	char *oacc;
  	char *ofm;
  	ftnint orl;
  	char *oblnk;
  } olist;
  
  /*close*/
  typedef struct
  {	flag cerr;
  	ftnint cunit;
  	char *csta;
  } cllist;
  
  /*rewind, backspace, endfile*/
  typedef struct
  {	flag aerr;
  	ftnint aunit;
  } alist;
  
  /* inquire */
  typedef struct
  {	flag inerr;
  	ftnint inunit;
  	char *infile;
  	ftnlen infilen;
  	ftnint	*inex;	/*parameters in standard's order*/
  	ftnint	*inopen;
  	ftnint	*innum;
  	ftnint	*innamed;
  	char	*inname;
  	ftnlen	innamlen;
  	char	*inacc;
  	ftnlen	inacclen;
  	char	*inseq;
  	ftnlen	inseqlen;
  	char 	*indir;
  	ftnlen	indirlen;
  	char	*infmt;
  	ftnlen	infmtlen;
  	char	*inform;
  	ftnint	informlen;
  	char	*inunf;
  	ftnlen	inunflen;
  	ftnint	*inrecl;
  	ftnint	*innrec;
  	char	*inblank;
  	ftnlen	inblanklen;
  } inlist;
  
  #define VOID void
  
  union Multitype {	/* for multiple entry points */
  	integer1 g;
  	shortint h;
  	integer i;
  	/* longint j; */
  	real r;
  	doublereal d;
  	complex c;
  	doublecomplex z;
  	};
  
  typedef union Multitype Multitype;
  
  struct Vardesc {	/* for Namelist */
  	char *name;
  	char *addr;
  	ftnlen *dims;
  	int  type;
  	};
  typedef struct Vardesc Vardesc;
  
  struct Namelist {
  	char *name;
  	Vardesc **vars;
  	int nvars;
  	};
  typedef struct Namelist Namelist;
  
  #define abs(x) ((x) >= 0 ? (x) : -(x))
  #define dabs(x) (fabs(x))
  #define f2cmin(a,b) ((a) <= (b) ? (a) : (b))
  #define f2cmax(a,b) ((a) >= (b) ? (a) : (b))
  #define dmin(a,b) (f2cmin(a,b))
  #define dmax(a,b) (f2cmax(a,b))
  #define bit_test(a,b)	((a) >> (b) & 1)
  #define bit_clear(a,b)	((a) & ~((uinteger)1 << (b)))
  #define bit_set(a,b)	((a) |  ((uinteger)1 << (b)))
  
  #define abort_() { sig_die("Fortran abort routine called", 1); }
  #define c_abs(z) (cabsf(Cf(z)))
  #define c_cos(R,Z) { pCf(R)=ccos(Cf(Z)); }
  #ifdef _MSC_VER
  #define c_div(c, a, b) {Cf(c)._Val[0] = (Cf(a)._Val[0]/Cf(b)._Val[0]); Cf(c)._Val[1]=(Cf(a)._Val[1]/Cf(b)._Val[1]);}
  #define z_div(c, a, b) {Cd(c)._Val[0] = (Cd(a)._Val[0]/Cd(b)._Val[0]); Cd(c)._Val[1]=(Cd(a)._Val[1]/df(b)._Val[1]);}
  #else
  #define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
  #define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
  #endif
  #define c_exp(R, Z) {pCf(R) = cexpf(Cf(Z));}
  #define c_log(R, Z) {pCf(R) = clogf(Cf(Z));}
  #define c_sin(R, Z) {pCf(R) = csinf(Cf(Z));}
  //#define c_sqrt(R, Z) {*(R) = csqrtf(Cf(Z));}
  #define c_sqrt(R, Z) {pCf(R) = csqrtf(Cf(Z));}
  #define d_abs(x) (fabs(*(x)))
  #define d_acos(x) (acos(*(x)))
  #define d_asin(x) (asin(*(x)))
  #define d_atan(x) (atan(*(x)))
  #define d_atn2(x, y) (atan2(*(x),*(y)))
  #define d_cnjg(R, Z) { pCd(R) = conj(Cd(Z)); }
  #define r_cnjg(R, Z) { pCf(R) = conjf(Cf(Z)); }
  #define d_cos(x) (cos(*(x)))
  #define d_cosh(x) (cosh(*(x)))
  #define d_dim(__a, __b) ( *(__a) > *(__b) ? *(__a) - *(__b) : 0.0 )
  #define d_exp(x) (exp(*(x)))
  #define d_imag(z) (cimag(Cd(z)))
  #define r_imag(z) (cimagf(Cf(z)))
  #define d_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
  #define r_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
  #define d_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
  #define r_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
  #define d_log(x) (log(*(x)))
  #define d_mod(x, y) (fmod(*(x), *(y)))
  #define u_nint(__x) ((__x)>=0 ? floor((__x) + .5) : -floor(.5 - (__x)))
  #define d_nint(x) u_nint(*(x))
  #define u_sign(__a,__b) ((__b) >= 0 ? ((__a) >= 0 ? (__a) : -(__a)) : -((__a) >= 0 ? (__a) : -(__a)))
  #define d_sign(a,b) u_sign(*(a),*(b))
  #define r_sign(a,b) u_sign(*(a),*(b))
  #define d_sin(x) (sin(*(x)))
  #define d_sinh(x) (sinh(*(x)))
  #define d_sqrt(x) (sqrt(*(x)))
  #define d_tan(x) (tan(*(x)))
  #define d_tanh(x) (tanh(*(x)))
  #define i_abs(x) abs(*(x))
  #define i_dnnt(x) ((integer)u_nint(*(x)))
  #define i_len(s, n) (n)
  #define i_nint(x) ((integer)u_nint(*(x)))
  #define i_sign(a,b) ((integer)u_sign((integer)*(a),(integer)*(b)))
  #define pow_dd(ap, bp) ( pow(*(ap), *(bp)))
  #define pow_si(B,E) spow_ui(*(B),*(E))
  #define pow_ri(B,E) spow_ui(*(B),*(E))
  #define pow_di(B,E) dpow_ui(*(B),*(E))
  #define pow_zi(p, a, b) {pCd(p) = zpow_ui(Cd(a), *(b));}
  #define pow_ci(p, a, b) {pCf(p) = cpow_ui(Cf(a), *(b));}
  #define pow_zz(R,A,B) {pCd(R) = cpow(Cd(A),*(B));}
  #define s_cat(lpp, rpp, rnp, np, llp) { 	ftnlen i, nc, ll; char *f__rp, *lp; 	ll = (llp); lp = (lpp); 	for(i=0; i < (int)*(np); ++i) {         	nc = ll; 	        if((rnp)[i] < nc) nc = (rnp)[i]; 	        ll -= nc;         	f__rp = (rpp)[i]; 	        while(--nc >= 0) *lp++ = *(f__rp)++;         } 	while(--ll >= 0) *lp++ = ' '; }
  #define s_cmp(a,b,c,d) ((integer)strncmp((a),(b),f2cmin((c),(d))))
  #define s_copy(A,B,C,D) { int __i,__m; for (__i=0, __m=f2cmin((C),(D)); __i<__m && (B)[__i] != 0; ++__i) (A)[__i] = (B)[__i]; }
  #define sig_die(s, kill) { exit(1); }
  #define s_stop(s, n) {exit(0);}
  static char junk[] = "\n@(#)LIBF77 VERSION 19990503\n";
  #define z_abs(z) (cabs(Cd(z)))
  #define z_exp(R, Z) {pCd(R) = cexp(Cd(Z));}
  #define z_sqrt(R, Z) {pCd(R) = csqrt(Cd(Z));}
  #define myexit_() break;
  #define mycycle() continue;
  #define myceiling(w) {ceil(w)}
  #define myhuge(w) {HUGE_VAL}
  //#define mymaxloc_(w,s,e,n) {if (sizeof(*(w)) == sizeof(double)) dmaxloc_((w),*(s),*(e),n); else dmaxloc_((w),*(s),*(e),n);}
  #define mymaxloc(w,s,e,n) {dmaxloc_(w,*(s),*(e),n)}
  
  /* procedure parameter types for -A and -C++ */
  
  #define F2C_proc_par_types 1
  #ifdef __cplusplus
  typedef logical (*L_fp)(...);
  #else
  typedef logical (*L_fp)();
  #endif
  
  static float spow_ui(float x, integer n) {
  	float pow=1.0; unsigned long int u;
  	if(n != 0) {
  		if(n < 0) n = -n, x = 1/x;
  		for(u = n; ; ) {
  			if(u & 01) pow *= x;
  			if(u >>= 1) x *= x;
  			else break;
  		}
  	}
  	return pow;
  }
  static double dpow_ui(double x, integer n) {
  	double pow=1.0; unsigned long int u;
  	if(n != 0) {
  		if(n < 0) n = -n, x = 1/x;
  		for(u = n; ; ) {
  			if(u & 01) pow *= x;
  			if(u >>= 1) x *= x;
  			else break;
  		}
  	}
  	return pow;
  }
  #ifdef _MSC_VER
  static _Fcomplex cpow_ui(complex x, integer n) {
  	complex pow={1.0,0.0}; unsigned long int u;
  		if(n != 0) {
  		if(n < 0) n = -n, x.r = 1/x.r, x.i=1/x.i;
  		for(u = n; ; ) {
  			if(u & 01) pow.r *= x.r, pow.i *= x.i;
  			if(u >>= 1) x.r *= x.r, x.i *= x.i;
  			else break;
  		}
  	}
  	_Fcomplex p={pow.r, pow.i};
  	return p;
  }
  #else
  static _Complex float cpow_ui(_Complex float x, integer n) {
  	_Complex float pow=1.0; unsigned long int u;
  	if(n != 0) {
  		if(n < 0) n = -n, x = 1/x;
  		for(u = n; ; ) {
  			if(u & 01) pow *= x;
  			if(u >>= 1) x *= x;
  			else break;
  		}
  	}
  	return pow;
  }
  #endif
  #ifdef _MSC_VER
  static _Dcomplex zpow_ui(_Dcomplex x, integer n) {
  	_Dcomplex pow={1.0,0.0}; unsigned long int u;
  	if(n != 0) {
  		if(n < 0) n = -n, x._Val[0] = 1/x._Val[0], x._Val[1] =1/x._Val[1];
  		for(u = n; ; ) {
  			if(u & 01) pow._Val[0] *= x._Val[0], pow._Val[1] *= x._Val[1];
  			if(u >>= 1) x._Val[0] *= x._Val[0], x._Val[1] *= x._Val[1];
  			else break;
  		}
  	}
  	_Dcomplex p = {pow._Val[0], pow._Val[1]};
  	return p;
  }
  #else
  static _Complex double zpow_ui(_Complex double x, integer n) {
  	_Complex double pow=1.0; unsigned long int u;
  	if(n != 0) {
  		if(n < 0) n = -n, x = 1/x;
  		for(u = n; ; ) {
  			if(u & 01) pow *= x;
  			if(u >>= 1) x *= x;
  			else break;
  		}
  	}
  	return pow;
  }
  #endif
  static integer pow_ii(integer x, integer n) {
  	integer pow; unsigned long int u;
  	if (n <= 0) {
  		if (n == 0 || x == 1) pow = 1;
  		else if (x != -1) pow = x == 0 ? 1/x : 0;
  		else n = -n;
  	}
  	if ((n > 0) || !(n == 0 || x == 1 || x != -1)) {
  		u = n;
  		for(pow = 1; ; ) {
  			if(u & 01) pow *= x;
  			if(u >>= 1) x *= x;
  			else break;
  		}
  	}
  	return pow;
  }
  static integer dmaxloc_(double *w, integer s, integer e, integer *n)
  {
  	double m; integer i, mi;
  	for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
  		if (w[i-1]>m) mi=i ,m=w[i-1];
  	return mi-s+1;
  }
  static integer smaxloc_(float *w, integer s, integer e, integer *n)
  {
  	float m; integer i, mi;
  	for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
  		if (w[i-1]>m) mi=i ,m=w[i-1];
  	return mi-s+1;
  }
  static inline void cdotc_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
  	integer n = *n_, incx = *incx_, incy = *incy_, i;
  #ifdef _MSC_VER
  	_Fcomplex zdotc = {0.0, 0.0};
  	if (incx == 1 && incy == 1) {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc._Val[0] += conjf(Cf(&x[i]))._Val[0] * Cf(&y[i])._Val[0];
  			zdotc._Val[1] += conjf(Cf(&x[i]))._Val[1] * Cf(&y[i])._Val[1];
  		}
  	} else {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc._Val[0] += conjf(Cf(&x[i*incx]))._Val[0] * Cf(&y[i*incy])._Val[0];
  			zdotc._Val[1] += conjf(Cf(&x[i*incx]))._Val[1] * Cf(&y[i*incy])._Val[1];
  		}
  	}
  	pCf(z) = zdotc;
  }
  #else
  	_Complex float zdotc = 0.0;
  	if (incx == 1 && incy == 1) {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc += conjf(Cf(&x[i])) * Cf(&y[i]);
  		}
  	} else {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc += conjf(Cf(&x[i*incx])) * Cf(&y[i*incy]);
  		}
  	}
  	pCf(z) = zdotc;
  }
  #endif
  static inline void zdotc_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
  	integer n = *n_, incx = *incx_, incy = *incy_, i;
  #ifdef _MSC_VER
  	_Dcomplex zdotc = {0.0, 0.0};
  	if (incx == 1 && incy == 1) {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc._Val[0] += conj(Cd(&x[i]))._Val[0] * Cd(&y[i])._Val[0];
  			zdotc._Val[1] += conj(Cd(&x[i]))._Val[1] * Cd(&y[i])._Val[1];
  		}
  	} else {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc._Val[0] += conj(Cd(&x[i*incx]))._Val[0] * Cd(&y[i*incy])._Val[0];
  			zdotc._Val[1] += conj(Cd(&x[i*incx]))._Val[1] * Cd(&y[i*incy])._Val[1];
  		}
  	}
  	pCd(z) = zdotc;
  }
  #else
  	_Complex double zdotc = 0.0;
  	if (incx == 1 && incy == 1) {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc += conj(Cd(&x[i])) * Cd(&y[i]);
  		}
  	} else {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc += conj(Cd(&x[i*incx])) * Cd(&y[i*incy]);
  		}
  	}
  	pCd(z) = zdotc;
  }
  #endif	
  static inline void cdotu_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
  	integer n = *n_, incx = *incx_, incy = *incy_, i;
  #ifdef _MSC_VER
  	_Fcomplex zdotc = {0.0, 0.0};
  	if (incx == 1 && incy == 1) {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc._Val[0] += Cf(&x[i])._Val[0] * Cf(&y[i])._Val[0];
  			zdotc._Val[1] += Cf(&x[i])._Val[1] * Cf(&y[i])._Val[1];
  		}
  	} else {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc._Val[0] += Cf(&x[i*incx])._Val[0] * Cf(&y[i*incy])._Val[0];
  			zdotc._Val[1] += Cf(&x[i*incx])._Val[1] * Cf(&y[i*incy])._Val[1];
  		}
  	}
  	pCf(z) = zdotc;
  }
  #else
  	_Complex float zdotc = 0.0;
  	if (incx == 1 && incy == 1) {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc += Cf(&x[i]) * Cf(&y[i]);
  		}
  	} else {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc += Cf(&x[i*incx]) * Cf(&y[i*incy]);
  		}
  	}
  	pCf(z) = zdotc;
  }
  #endif
  static inline void zdotu_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
  	integer n = *n_, incx = *incx_, incy = *incy_, i;
  #ifdef _MSC_VER
  	_Dcomplex zdotc = {0.0, 0.0};
  	if (incx == 1 && incy == 1) {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc._Val[0] += Cd(&x[i])._Val[0] * Cd(&y[i])._Val[0];
  			zdotc._Val[1] += Cd(&x[i])._Val[1] * Cd(&y[i])._Val[1];
  		}
  	} else {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc._Val[0] += Cd(&x[i*incx])._Val[0] * Cd(&y[i*incy])._Val[0];
  			zdotc._Val[1] += Cd(&x[i*incx])._Val[1] * Cd(&y[i*incy])._Val[1];
  		}
  	}
  	pCd(z) = zdotc;
  }
  #else
  	_Complex double zdotc = 0.0;
  	if (incx == 1 && incy == 1) {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc += Cd(&x[i]) * Cd(&y[i]);
  		}
  	} else {
  		for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  			zdotc += Cd(&x[i*incx]) * Cd(&y[i*incy]);
  		}
  	}
  	pCd(z) = zdotc;
  }
  #endif
  /*  -- translated by f2c (version 20000121).
     You must link the resulting object file with the libraries:
  	-lf2c -lm   (in that order)
  */
  
  
  
  
  /* Table of constant values */
  
  static complex c_b1 = {0.f,0.f};
  static complex c_b2 = {1.f,0.f};
  static integer c__1 = 1;
  static integer c__0 = 0;
  static integer c_n1 = -1;
  
  /* > \brief <b> CGGESX computes the eigenvalues, the Schur form, and, optionally, the matrix of Schur vectors 
  for GE matrices</b> */
  
  /*  =========== DOCUMENTATION =========== */
  
  /* Online html documentation available at */
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  /* > \htmlonly */
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  f"> */
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  f"> */
  /* > [ZIP]</a> */
  /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/cggesx.
  f"> */
  /* > [TXT]</a> */
  /* > \endhtmlonly */
  
  /*  Definition: */
  /*  =========== */
  
  /*       SUBROUTINE CGGESX( JOBVSL, JOBVSR, SORT, SELCTG, SENSE, N, A, LDA, */
  /*                          B, LDB, SDIM, ALPHA, BETA, VSL, LDVSL, VSR, */
  /*                          LDVSR, RCONDE, RCONDV, WORK, LWORK, RWORK, */
  /*                          IWORK, LIWORK, BWORK, INFO ) */
  
  /*       CHARACTER          JOBVSL, JOBVSR, SENSE, SORT */
  /*       INTEGER            INFO, LDA, LDB, LDVSL, LDVSR, LIWORK, LWORK, N, */
  /*      $                   SDIM */
  /*       LOGICAL            BWORK( * ) */
  /*       INTEGER            IWORK( * ) */
  /*       REAL               RCONDE( 2 ), RCONDV( 2 ), RWORK( * ) */
  /*       COMPLEX            A( LDA, * ), ALPHA( * ), B( LDB, * ), */
  /*      $                   BETA( * ), VSL( LDVSL, * ), VSR( LDVSR, * ), */
  /*      $                   WORK( * ) */
  /*       LOGICAL            SELCTG */
  /*       EXTERNAL           SELCTG */
  
  
  /* > \par Purpose: */
  /*  ============= */
  /* > */
  /* > \verbatim */
  /* > */
  /* > CGGESX computes for a pair of N-by-N complex nonsymmetric matrices */
  /* > (A,B), the generalized eigenvalues, the complex Schur form (S,T), */
  /* > and, optionally, the left and/or right matrices of Schur vectors (VSL */
  /* > and VSR).  This gives the generalized Schur factorization */
  /* > */
  /* >      (A,B) = ( (VSL) S (VSR)**H, (VSL) T (VSR)**H ) */
  /* > */
  /* > where (VSR)**H is the conjugate-transpose of VSR. */
  /* > */
  /* > Optionally, it also orders the eigenvalues so that a selected cluster */
  /* > of eigenvalues appears in the leading diagonal blocks of the upper */
  /* > triangular matrix S and the upper triangular matrix T; computes */
  /* > a reciprocal condition number for the average of the selected */
  /* > eigenvalues (RCONDE); and computes a reciprocal condition number for */
  /* > the right and left deflating subspaces corresponding to the selected */
  /* > eigenvalues (RCONDV). The leading columns of VSL and VSR then form */
  /* > an orthonormal basis for the corresponding left and right eigenspaces */
  /* > (deflating subspaces). */
  /* > */
  /* > A generalized eigenvalue for a pair of matrices (A,B) is a scalar w */
  /* > or a ratio alpha/beta = w, such that  A - w*B is singular.  It is */
  /* > usually represented as the pair (alpha,beta), as there is a */
  /* > reasonable interpretation for beta=0 or for both being zero. */
  /* > */
  /* > A pair of matrices (S,T) is in generalized complex Schur form if T is */
  /* > upper triangular with non-negative diagonal and S is upper */
  /* > triangular. */
  /* > \endverbatim */
  
  /*  Arguments: */
  /*  ========== */
  
  /* > \param[in] JOBVSL */
  /* > \verbatim */
  /* >          JOBVSL is CHARACTER*1 */
  /* >          = 'N':  do not compute the left Schur vectors; */
  /* >          = 'V':  compute the left Schur vectors. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] JOBVSR */
  /* > \verbatim */
  /* >          JOBVSR is CHARACTER*1 */
  /* >          = 'N':  do not compute the right Schur vectors; */
  /* >          = 'V':  compute the right Schur vectors. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] SORT */
  /* > \verbatim */
  /* >          SORT is CHARACTER*1 */
  /* >          Specifies whether or not to order the eigenvalues on the */
  /* >          diagonal of the generalized Schur form. */
  /* >          = 'N':  Eigenvalues are not ordered; */
  /* >          = 'S':  Eigenvalues are ordered (see SELCTG). */
  /* > \endverbatim */
  /* > */
  /* > \param[in] SELCTG */
  /* > \verbatim */
  /* >          SELCTG is a LOGICAL FUNCTION of two COMPLEX arguments */
  /* >          SELCTG must be declared EXTERNAL in the calling subroutine. */
  /* >          If SORT = 'N', SELCTG is not referenced. */
  /* >          If SORT = 'S', SELCTG is used to select eigenvalues to sort */
  /* >          to the top left of the Schur form. */
  /* >          Note that a selected complex eigenvalue may no longer satisfy */
  /* >          SELCTG(ALPHA(j),BETA(j)) = .TRUE. after ordering, since */
  /* >          ordering may change the value of complex eigenvalues */
  /* >          (especially if the eigenvalue is ill-conditioned), in this */
  /* >          case INFO is set to N+3 see INFO below). */
  /* > \endverbatim */
  /* > */
  /* > \param[in] SENSE */
  /* > \verbatim */
  /* >          SENSE is CHARACTER*1 */
  /* >          Determines which reciprocal condition numbers are computed. */
  /* >          = 'N':  None are computed; */
  /* >          = 'E':  Computed for average of selected eigenvalues only; */
  /* >          = 'V':  Computed for selected deflating subspaces only; */
  /* >          = 'B':  Computed for both. */
  /* >          If SENSE = 'E', 'V', or 'B', SORT must equal 'S'. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] N */
  /* > \verbatim */
  /* >          N is INTEGER */
  /* >          The order of the matrices A, B, VSL, and VSR.  N >= 0. */
  /* > \endverbatim */
  /* > */
  /* > \param[in,out] A */
  /* > \verbatim */
  /* >          A is COMPLEX array, dimension (LDA, N) */
  /* >          On entry, the first of the pair of matrices. */
  /* >          On exit, A has been overwritten by its generalized Schur */
  /* >          form S. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] LDA */
  /* > \verbatim */
  /* >          LDA is INTEGER */
  /* >          The leading dimension of A.  LDA >= f2cmax(1,N). */
  /* > \endverbatim */
  /* > */
  /* > \param[in,out] B */
  /* > \verbatim */
  /* >          B is COMPLEX array, dimension (LDB, N) */
  /* >          On entry, the second of the pair of matrices. */
  /* >          On exit, B has been overwritten by its generalized Schur */
  /* >          form T. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] LDB */
  /* > \verbatim */
  /* >          LDB is INTEGER */
  /* >          The leading dimension of B.  LDB >= f2cmax(1,N). */
  /* > \endverbatim */
  /* > */
  /* > \param[out] SDIM */
  /* > \verbatim */
  /* >          SDIM is INTEGER */
  /* >          If SORT = 'N', SDIM = 0. */
  /* >          If SORT = 'S', SDIM = number of eigenvalues (after sorting) */
  /* >          for which SELCTG is true. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] ALPHA */
  /* > \verbatim */
  /* >          ALPHA is COMPLEX array, dimension (N) */
  /* > \endverbatim */
  /* > */
  /* > \param[out] BETA */
  /* > \verbatim */
  /* >          BETA is COMPLEX array, dimension (N) */
  /* >          On exit, ALPHA(j)/BETA(j), j=1,...,N, will be the */
  /* >          generalized eigenvalues.  ALPHA(j) and BETA(j),j=1,...,N  are */
  /* >          the diagonals of the complex Schur form (S,T).  BETA(j) will */
  /* >          be non-negative real. */
  /* > */
  /* >          Note: the quotients ALPHA(j)/BETA(j) may easily over- or */
  /* >          underflow, and BETA(j) may even be zero.  Thus, the user */
  /* >          should avoid naively computing the ratio alpha/beta. */
  /* >          However, ALPHA will be always less than and usually */
  /* >          comparable with norm(A) in magnitude, and BETA always less */
  /* >          than and usually comparable with norm(B). */
  /* > \endverbatim */
  /* > */
  /* > \param[out] VSL */
  /* > \verbatim */
  /* >          VSL is COMPLEX array, dimension (LDVSL,N) */
  /* >          If JOBVSL = 'V', VSL will contain the left Schur vectors. */
  /* >          Not referenced if JOBVSL = 'N'. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] LDVSL */
  /* > \verbatim */
  /* >          LDVSL is INTEGER */
  /* >          The leading dimension of the matrix VSL. LDVSL >=1, and */
  /* >          if JOBVSL = 'V', LDVSL >= N. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] VSR */
  /* > \verbatim */
  /* >          VSR is COMPLEX array, dimension (LDVSR,N) */
  /* >          If JOBVSR = 'V', VSR will contain the right Schur vectors. */
  /* >          Not referenced if JOBVSR = 'N'. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] LDVSR */
  /* > \verbatim */
  /* >          LDVSR is INTEGER */
  /* >          The leading dimension of the matrix VSR. LDVSR >= 1, and */
  /* >          if JOBVSR = 'V', LDVSR >= N. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] RCONDE */
  /* > \verbatim */
  /* >          RCONDE is REAL array, dimension ( 2 ) */
  /* >          If SENSE = 'E' or 'B', RCONDE(1) and RCONDE(2) contain the */
  /* >          reciprocal condition numbers for the average of the selected */
  /* >          eigenvalues. */
  /* >          Not referenced if SENSE = 'N' or 'V'. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] RCONDV */
  /* > \verbatim */
  /* >          RCONDV is REAL array, dimension ( 2 ) */
  /* >          If SENSE = 'V' or 'B', RCONDV(1) and RCONDV(2) contain the */
  /* >          reciprocal condition number for the selected deflating */
  /* >          subspaces. */
  /* >          Not referenced if SENSE = 'N' or 'E'. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] WORK */
  /* > \verbatim */
  /* >          WORK is COMPLEX array, dimension (MAX(1,LWORK)) */
  /* >          On exit, if INFO = 0, WORK(1) returns the optimal LWORK. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] LWORK */
  /* > \verbatim */
  /* >          LWORK is INTEGER */
  /* >          The dimension of the array WORK. */
  /* >          If N = 0, LWORK >= 1, else if SENSE = 'E', 'V', or 'B', */
  /* >          LWORK >= MAX(1,2*N,2*SDIM*(N-SDIM)), else */
  /* >          LWORK >= MAX(1,2*N).  Note that 2*SDIM*(N-SDIM) <= N*N/2. */
  /* >          Note also that an error is only returned if */
  /* >          LWORK < MAX(1,2*N), but if SENSE = 'E' or 'V' or 'B' this may */
  /* >          not be large enough. */
  /* > */
  /* >          If LWORK = -1, then a workspace query is assumed; the routine */
  /* >          only calculates the bound on the optimal size of the WORK */
  /* >          array and the minimum size of the IWORK array, returns these */
  /* >          values as the first entries of the WORK and IWORK arrays, and */
  /* >          no error message related to LWORK or LIWORK is issued by */
  /* >          XERBLA. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] RWORK */
  /* > \verbatim */
  /* >          RWORK is REAL array, dimension ( 8*N ) */
  /* >          Real workspace. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] IWORK */
  /* > \verbatim */
  /* >          IWORK is INTEGER array, dimension (MAX(1,LIWORK)) */
  /* >          On exit, if INFO = 0, IWORK(1) returns the minimum LIWORK. */
  /* > \endverbatim */
  /* > */
  /* > \param[in] LIWORK */
  /* > \verbatim */
  /* >          LIWORK is INTEGER */
  /* >          The dimension of the array WORK. */
  /* >          If SENSE = 'N' or N = 0, LIWORK >= 1, otherwise */
  /* >          LIWORK >= N+2. */
  /* > */
  /* >          If LIWORK = -1, then a workspace query is assumed; the */
  /* >          routine only calculates the bound on the optimal size of the */
  /* >          WORK array and the minimum size of the IWORK array, returns */
  /* >          these values as the first entries of the WORK and IWORK */
  /* >          arrays, and no error message related to LWORK or LIWORK is */
  /* >          issued by XERBLA. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] BWORK */
  /* > \verbatim */
  /* >          BWORK is LOGICAL array, dimension (N) */
  /* >          Not referenced if SORT = 'N'. */
  /* > \endverbatim */
  /* > */
  /* > \param[out] INFO */
  /* > \verbatim */
  /* >          INFO is INTEGER */
  /* >          = 0:  successful exit */
  /* >          < 0:  if INFO = -i, the i-th argument had an illegal value. */
  /* >          = 1,...,N: */
  /* >                The QZ iteration failed.  (A,B) are not in Schur */
  /* >                form, but ALPHA(j) and BETA(j) should be correct for */
  /* >                j=INFO+1,...,N. */
  /* >          > N:  =N+1: other than QZ iteration failed in CHGEQZ */
  /* >                =N+2: after reordering, roundoff changed values of */
  /* >                      some complex eigenvalues so that leading */
  /* >                      eigenvalues in the Generalized Schur form no */
  /* >                      longer satisfy SELCTG=.TRUE.  This could also */
  /* >                      be caused due to scaling. */
  /* >                =N+3: reordering failed in CTGSEN. */
  /* > \endverbatim */
  
  /*  Authors: */
  /*  ======== */
  
  /* > \author Univ. of Tennessee */
  /* > \author Univ. of California Berkeley */
  /* > \author Univ. of Colorado Denver */
  /* > \author NAG Ltd. */
  
  /* > \date June 2017 */
  
  /* > \ingroup complexGEeigen */
  
  /*  ===================================================================== */
  /* Subroutine */ int cggesx_(char *jobvsl, char *jobvsr, char *sort, L_fp 
  	selctg, char *sense, integer *n, complex *a, integer *lda, complex *b,
  	 integer *ldb, integer *sdim, complex *alpha, complex *beta, complex *
  	vsl, integer *ldvsl, complex *vsr, integer *ldvsr, real *rconde, real 
  	*rcondv, complex *work, integer *lwork, real *rwork, integer *iwork, 
  	integer *liwork, logical *bwork, integer *info)
  {
      /* System generated locals */
      integer a_dim1, a_offset, b_dim1, b_offset, vsl_dim1, vsl_offset, 
  	    vsr_dim1, vsr_offset, i__1, i__2;
  
      /* Local variables */
      integer ijob;
      real anrm, bnrm;
      integer ierr, itau, iwrk, lwrk, i__;
      extern logical lsame_(char *, char *);
      integer ileft, icols;
      logical cursl, ilvsl, ilvsr;
      integer irwrk, irows;
      extern /* Subroutine */ int cggbak_(char *, char *, integer *, integer *, 
  	    integer *, real *, real *, integer *, complex *, integer *, 
  	    integer *), cggbal_(char *, integer *, complex *, 
  	    integer *, complex *, integer *, integer *, integer *, real *, 
  	    real *, real *, integer *), slabad_(real *, real *);
      extern real clange_(char *, integer *, integer *, complex *, integer *, 
  	    real *);
      real pl;
      extern /* Subroutine */ int cgghrd_(char *, char *, integer *, integer *, 
  	    integer *, complex *, integer *, complex *, integer *, complex *, 
  	    integer *, complex *, integer *, integer *), 
  	    clascl_(char *, integer *, integer *, real *, real *, integer *, 
  	    integer *, complex *, integer *, integer *);
      real pr;
      logical ilascl, ilbscl;
      extern /* Subroutine */ int cgeqrf_(integer *, integer *, complex *, 
  	    integer *, complex *, complex *, integer *, integer *), clacpy_(
  	    char *, integer *, integer *, complex *, integer *, complex *, 
  	    integer *), claset_(char *, integer *, integer *, complex 
  	    *, complex *, complex *, integer *), xerbla_(char *, 
  	    integer *, ftnlen);
      extern integer ilaenv_(integer *, char *, char *, integer *, integer *, 
  	    integer *, integer *, ftnlen, ftnlen);
      extern real slamch_(char *);
      real bignum;
      extern /* Subroutine */ int chgeqz_(char *, char *, char *, integer *, 
  	    integer *, integer *, complex *, integer *, complex *, integer *, 
  	    complex *, complex *, complex *, integer *, complex *, integer *, 
  	    complex *, integer *, real *, integer *), 
  	    ctgsen_(integer *, logical *, logical *, logical *, integer *, 
  	    complex *, integer *, complex *, integer *, complex *, complex *, 
  	    complex *, integer *, complex *, integer *, integer *, real *, 
  	    real *, real *, complex *, integer *, integer *, integer *, 
  	    integer *);
      integer ijobvl, iright, ijobvr;
      logical wantsb;
      integer liwmin;
      logical wantse, lastsl;
      real anrmto, bnrmto;
      extern /* Subroutine */ int cungqr_(integer *, integer *, integer *, 
  	    complex *, integer *, complex *, complex *, integer *, integer *);
      integer minwrk, maxwrk;
      logical wantsn;
      real smlnum;
      extern /* Subroutine */ int cunmqr_(char *, char *, integer *, integer *, 
  	    integer *, complex *, integer *, complex *, complex *, integer *, 
  	    complex *, integer *, integer *);
      logical wantst, lquery, wantsv;
      real dif[2];
      integer ihi, ilo;
      real eps;
  
  
  /*  -- LAPACK driver routine (version 3.7.1) -- */
  /*  -- LAPACK is a software package provided by Univ. of Tennessee,    -- */
  /*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
  /*     June 2017 */
  
  
  /*  ===================================================================== */
  
  
  /*     Decode the input arguments */
  
      /* Parameter adjustments */
      a_dim1 = *lda;
      a_offset = 1 + a_dim1 * 1;
      a -= a_offset;
      b_dim1 = *ldb;
      b_offset = 1 + b_dim1 * 1;
      b -= b_offset;
      --alpha;
      --beta;
      vsl_dim1 = *ldvsl;
      vsl_offset = 1 + vsl_dim1 * 1;
      vsl -= vsl_offset;
      vsr_dim1 = *ldvsr;
      vsr_offset = 1 + vsr_dim1 * 1;
      vsr -= vsr_offset;
      --rconde;
      --rcondv;
      --work;
      --rwork;
      --iwork;
      --bwork;
  
      /* Function Body */
      if (lsame_(jobvsl, "N")) {
  	ijobvl = 1;
  	ilvsl = FALSE_;
      } else if (lsame_(jobvsl, "V")) {
  	ijobvl = 2;
  	ilvsl = TRUE_;
      } else {
  	ijobvl = -1;
  	ilvsl = FALSE_;
      }
  
      if (lsame_(jobvsr, "N")) {
  	ijobvr = 1;
  	ilvsr = FALSE_;
      } else if (lsame_(jobvsr, "V")) {
  	ijobvr = 2;
  	ilvsr = TRUE_;
      } else {
  	ijobvr = -1;
  	ilvsr = FALSE_;
      }
  
      wantst = lsame_(sort, "S");
      wantsn = lsame_(sense, "N");
      wantse = lsame_(sense, "E");
      wantsv = lsame_(sense, "V");
      wantsb = lsame_(sense, "B");
      lquery = *lwork == -1 || *liwork == -1;
      if (wantsn) {
  	ijob = 0;
      } else if (wantse) {
  	ijob = 1;
      } else if (wantsv) {
  	ijob = 2;
      } else if (wantsb) {
  	ijob = 4;
      }
  
  /*     Test the input arguments */
  
      *info = 0;
      if (ijobvl <= 0) {
  	*info = -1;
      } else if (ijobvr <= 0) {
  	*info = -2;
      } else if (! wantst && ! lsame_(sort, "N")) {
  	*info = -3;
      } else if (! (wantsn || wantse || wantsv || wantsb) || ! wantst && ! 
  	    wantsn) {
  	*info = -5;
      } else if (*n < 0) {
  	*info = -6;
      } else if (*lda < f2cmax(1,*n)) {
  	*info = -8;
      } else if (*ldb < f2cmax(1,*n)) {
  	*info = -10;
      } else if (*ldvsl < 1 || ilvsl && *ldvsl < *n) {
  	*info = -15;
      } else if (*ldvsr < 1 || ilvsr && *ldvsr < *n) {
  	*info = -17;
      }
  
  /*     Compute workspace */
  /*      (Note: Comments in the code beginning "Workspace:" describe the */
  /*       minimal amount of workspace needed at that point in the code, */
  /*       as well as the preferred amount for good performance. */
  /*       NB refers to the optimal block size for the immediately */
  /*       following subroutine, as returned by ILAENV.) */
  
      if (*info == 0) {
  	if (*n > 0) {
  	    minwrk = *n << 1;
  	    maxwrk = *n * (ilaenv_(&c__1, "CGEQRF", " ", n, &c__1, n, &c__0, (
  		    ftnlen)6, (ftnlen)1) + 1);
  /* Computing MAX */
  	    i__1 = maxwrk, i__2 = *n * (ilaenv_(&c__1, "CUNMQR", " ", n, &
  		    c__1, n, &c_n1, (ftnlen)6, (ftnlen)1) + 1);
  	    maxwrk = f2cmax(i__1,i__2);
  	    if (ilvsl) {
  /* Computing MAX */
  		i__1 = maxwrk, i__2 = *n * (ilaenv_(&c__1, "CUNGQR", " ", n, &
  			c__1, n, &c_n1, (ftnlen)6, (ftnlen)1) + 1);
  		maxwrk = f2cmax(i__1,i__2);
  	    }
  	    lwrk = maxwrk;
  	    if (ijob >= 1) {
  /* Computing MAX */
  		i__1 = lwrk, i__2 = *n * *n / 2;
  		lwrk = f2cmax(i__1,i__2);
  	    }
  	} else {
  	    minwrk = 1;
  	    maxwrk = 1;
  	    lwrk = 1;
  	}
  	work[1].r = (real) lwrk, work[1].i = 0.f;
  	if (wantsn || *n == 0) {
  	    liwmin = 1;
  	} else {
  	    liwmin = *n + 2;
  	}
  	iwork[1] = liwmin;
  
  	if (*lwork < minwrk && ! lquery) {
  	    *info = -21;
  	} else if (*liwork < liwmin && ! lquery) {
  	    *info = -24;
  	}
      }
  
      if (*info != 0) {
  	i__1 = -(*info);
  	xerbla_("CGGESX", &i__1, (ftnlen)6);
  	return 0;
      } else if (lquery) {
  	return 0;
      }
  
  /*     Quick return if possible */
  
      if (*n == 0) {
  	*sdim = 0;
  	return 0;
      }
  
  /*     Get machine constants */
  
      eps = slamch_("P");
      smlnum = slamch_("S");
      bignum = 1.f / smlnum;
      slabad_(&smlnum, &bignum);
      smlnum = sqrt(smlnum) / eps;
      bignum = 1.f / smlnum;
  
  /*     Scale A if f2cmax element outside range [SMLNUM,BIGNUM] */
  
      anrm = clange_("M", n, n, &a[a_offset], lda, &rwork[1]);
      ilascl = FALSE_;
      if (anrm > 0.f && anrm < smlnum) {
  	anrmto = smlnum;
  	ilascl = TRUE_;
      } else if (anrm > bignum) {
  	anrmto = bignum;
  	ilascl = TRUE_;
      }
      if (ilascl) {
  	clascl_("G", &c__0, &c__0, &anrm, &anrmto, n, n, &a[a_offset], lda, &
  		ierr);
      }
  
  /*     Scale B if f2cmax element outside range [SMLNUM,BIGNUM] */
  
      bnrm = clange_("M", n, n, &b[b_offset], ldb, &rwork[1]);
      ilbscl = FALSE_;
      if (bnrm > 0.f && bnrm < smlnum) {
  	bnrmto = smlnum;
  	ilbscl = TRUE_;
      } else if (bnrm > bignum) {
  	bnrmto = bignum;
  	ilbscl = TRUE_;
      }
      if (ilbscl) {
  	clascl_("G", &c__0, &c__0, &bnrm, &bnrmto, n, n, &b[b_offset], ldb, &
  		ierr);
      }
  
  /*     Permute the matrix to make it more nearly triangular */
  /*     (Real Workspace: need 6*N) */
  
      ileft = 1;
      iright = *n + 1;
      irwrk = iright + *n;
      cggbal_("P", n, &a[a_offset], lda, &b[b_offset], ldb, &ilo, &ihi, &rwork[
  	    ileft], &rwork[iright], &rwork[irwrk], &ierr);
  
  /*     Reduce B to triangular form (QR decomposition of B) */
  /*     (Complex Workspace: need N, prefer N*NB) */
  
      irows = ihi + 1 - ilo;
      icols = *n + 1 - ilo;
      itau = 1;
      iwrk = itau + irows;
      i__1 = *lwork + 1 - iwrk;
      cgeqrf_(&irows, &icols, &b[ilo + ilo * b_dim1], ldb, &work[itau], &work[
  	    iwrk], &i__1, &ierr);
  
  /*     Apply the unitary transformation to matrix A */
  /*     (Complex Workspace: need N, prefer N*NB) */
  
      i__1 = *lwork + 1 - iwrk;
      cunmqr_("L", "C", &irows, &icols, &irows, &b[ilo + ilo * b_dim1], ldb, &
  	    work[itau], &a[ilo + ilo * a_dim1], lda, &work[iwrk], &i__1, &
  	    ierr);
  
  /*     Initialize VSL */
  /*     (Complex Workspace: need N, prefer N*NB) */
  
      if (ilvsl) {
  	claset_("Full", n, n, &c_b1, &c_b2, &vsl[vsl_offset], ldvsl);
  	if (irows > 1) {
  	    i__1 = irows - 1;
  	    i__2 = irows - 1;
  	    clacpy_("L", &i__1, &i__2, &b[ilo + 1 + ilo * b_dim1], ldb, &vsl[
  		    ilo + 1 + ilo * vsl_dim1], ldvsl);
  	}
  	i__1 = *lwork + 1 - iwrk;
  	cungqr_(&irows, &irows, &irows, &vsl[ilo + ilo * vsl_dim1], ldvsl, &
  		work[itau], &work[iwrk], &i__1, &ierr);
      }
  
  /*     Initialize VSR */
  
      if (ilvsr) {
  	claset_("Full", n, n, &c_b1, &c_b2, &vsr[vsr_offset], ldvsr);
      }
  
  /*     Reduce to generalized Hessenberg form */
  /*     (Workspace: none needed) */
  
      cgghrd_(jobvsl, jobvsr, n, &ilo, &ihi, &a[a_offset], lda, &b[b_offset], 
  	    ldb, &vsl[vsl_offset], ldvsl, &vsr[vsr_offset], ldvsr, &ierr);
  
      *sdim = 0;
  
  /*     Perform QZ algorithm, computing Schur vectors if desired */
  /*     (Complex Workspace: need N) */
  /*     (Real Workspace:    need N) */
  
      iwrk = itau;
      i__1 = *lwork + 1 - iwrk;
      chgeqz_("S", jobvsl, jobvsr, n, &ilo, &ihi, &a[a_offset], lda, &b[
  	    b_offset], ldb, &alpha[1], &beta[1], &vsl[vsl_offset], ldvsl, &
  	    vsr[vsr_offset], ldvsr, &work[iwrk], &i__1, &rwork[irwrk], &ierr);
      if (ierr != 0) {
  	if (ierr > 0 && ierr <= *n) {
  	    *info = ierr;
  	} else if (ierr > *n && ierr <= *n << 1) {
  	    *info = ierr - *n;
  	} else {
  	    *info = *n + 1;
  	}
  	goto L40;
      }
  
  /*     Sort eigenvalues ALPHA/BETA and compute the reciprocal of */
  /*     condition number(s) */
  
      if (wantst) {
  
  /*        Undo scaling on eigenvalues before SELCTGing */
  
  	if (ilascl) {
  	    clascl_("G", &c__0, &c__0, &anrmto, &anrm, n, &c__1, &alpha[1], n,
  		     &ierr);
  	}
  	if (ilbscl) {
  	    clascl_("G", &c__0, &c__0, &bnrmto, &bnrm, n, &c__1, &beta[1], n, 
  		    &ierr);
  	}
  
  /*        Select eigenvalues */
  
  	i__1 = *n;
  	for (i__ = 1; i__ <= i__1; ++i__) {
  	    bwork[i__] = (*selctg)(&alpha[i__], &beta[i__]);
  /* L10: */
  	}
  
  /*        Reorder eigenvalues, transform Generalized Schur vectors, and */
  /*        compute reciprocal condition numbers */
  /*        (Complex Workspace: If IJOB >= 1, need MAX(1, 2*SDIM*(N-SDIM)) */
  /*                            otherwise, need 1 ) */
  
  	i__1 = *lwork - iwrk + 1;
  	ctgsen_(&ijob, &ilvsl, &ilvsr, &bwork[1], n, &a[a_offset], lda, &b[
  		b_offset], ldb, &alpha[1], &beta[1], &vsl[vsl_offset], ldvsl, 
  		&vsr[vsr_offset], ldvsr, sdim, &pl, &pr, dif, &work[iwrk], &
  		i__1, &iwork[1], liwork, &ierr);
  
  	if (ijob >= 1) {
  /* Computing MAX */
  	    i__1 = maxwrk, i__2 = (*sdim << 1) * (*n - *sdim);
  	    maxwrk = f2cmax(i__1,i__2);
  	}
  	if (ierr == -21) {
  
  /*            not enough complex workspace */
  
  	    *info = -21;
  	} else {
  	    if (ijob == 1 || ijob == 4) {
  		rconde[1] = pl;
  		rconde[2] = pr;
  	    }
  	    if (ijob == 2 || ijob == 4) {
  		rcondv[1] = dif[0];
  		rcondv[2] = dif[1];
  	    }
  	    if (ierr == 1) {
  		*info = *n + 3;
  	    }
  	}
  
      }
  
  /*     Apply permutation to VSL and VSR */
  /*     (Workspace: none needed) */
  
      if (ilvsl) {
  	cggbak_("P", "L", n, &ilo, &ihi, &rwork[ileft], &rwork[iright], n, &
  		vsl[vsl_offset], ldvsl, &ierr);
      }
  
      if (ilvsr) {
  	cggbak_("P", "R", n, &ilo, &ihi, &rwork[ileft], &rwork[iright], n, &
  		vsr[vsr_offset], ldvsr, &ierr);
      }
  
  /*     Undo scaling */
  
      if (ilascl) {
  	clascl_("U", &c__0, &c__0, &anrmto, &anrm, n, n, &a[a_offset], lda, &
  		ierr);
  	clascl_("G", &c__0, &c__0, &anrmto, &anrm, n, &c__1, &alpha[1], n, &
  		ierr);
      }
  
      if (ilbscl) {
  	clascl_("U", &c__0, &c__0, &bnrmto, &bnrm, n, n, &b[b_offset], ldb, &
  		ierr);
  	clascl_("G", &c__0, &c__0, &bnrmto, &bnrm, n, &c__1, &beta[1], n, &
  		ierr);
      }
  
      if (wantst) {
  
  /*        Check if reordering is correct */
  
  	lastsl = TRUE_;
  	*sdim = 0;
  	i__1 = *n;
  	for (i__ = 1; i__ <= i__1; ++i__) {
  	    cursl = (*selctg)(&alpha[i__], &beta[i__]);
  	    if (cursl) {
  		++(*sdim);
  	    }
  	    if (cursl && ! lastsl) {
  		*info = *n + 2;
  	    }
  	    lastsl = cursl;
  /* L30: */
  	}
  
      }
  
  L40:
  
      work[1].r = (real) maxwrk, work[1].i = 0.f;
      iwork[1] = liwmin;
  
      return 0;
  
  /*     End of CGGESX */
  
  } /* cggesx_ */
  
  