OpenBLAS/lapack-netlib/SRC/ztgevc.c

1555 lines
43 KiB
C

#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 blasint logical;
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]/Cd(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++ */
#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 doublecomplex c_b1 = {0.,0.};
static doublecomplex c_b2 = {1.,0.};
static integer c__1 = 1;
/* > \brief \b ZTGEVC */
/* =========== DOCUMENTATION =========== */
/* Online html documentation available at */
/* http://www.netlib.org/lapack/explore-html/ */
/* > \htmlonly */
/* > Download ZTGEVC + dependencies */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/ztgevc.
f"> */
/* > [TGZ]</a> */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/ztgevc.
f"> */
/* > [ZIP]</a> */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/ztgevc.
f"> */
/* > [TXT]</a> */
/* > \endhtmlonly */
/* Definition: */
/* =========== */
/* SUBROUTINE ZTGEVC( SIDE, HOWMNY, SELECT, N, S, LDS, P, LDP, VL, */
/* LDVL, VR, LDVR, MM, M, WORK, RWORK, INFO ) */
/* CHARACTER HOWMNY, SIDE */
/* INTEGER INFO, LDP, LDS, LDVL, LDVR, M, MM, N */
/* LOGICAL SELECT( * ) */
/* DOUBLE PRECISION RWORK( * ) */
/* COMPLEX*16 P( LDP, * ), S( LDS, * ), VL( LDVL, * ), */
/* $ VR( LDVR, * ), WORK( * ) */
/* > \par Purpose: */
/* ============= */
/* > */
/* > \verbatim */
/* > */
/* > ZTGEVC computes some or all of the right and/or left eigenvectors of */
/* > a pair of complex matrices (S,P), where S and P are upper triangular. */
/* > Matrix pairs of this type are produced by the generalized Schur */
/* > factorization of a complex matrix pair (A,B): */
/* > */
/* > A = Q*S*Z**H, B = Q*P*Z**H */
/* > */
/* > as computed by ZGGHRD + ZHGEQZ. */
/* > */
/* > The right eigenvector x and the left eigenvector y of (S,P) */
/* > corresponding to an eigenvalue w are defined by: */
/* > */
/* > S*x = w*P*x, (y**H)*S = w*(y**H)*P, */
/* > */
/* > where y**H denotes the conjugate tranpose of y. */
/* > The eigenvalues are not input to this routine, but are computed */
/* > directly from the diagonal elements of S and P. */
/* > */
/* > This routine returns the matrices X and/or Y of right and left */
/* > eigenvectors of (S,P), or the products Z*X and/or Q*Y, */
/* > where Z and Q are input matrices. */
/* > If Q and Z are the unitary factors from the generalized Schur */
/* > factorization of a matrix pair (A,B), then Z*X and Q*Y */
/* > are the matrices of right and left eigenvectors of (A,B). */
/* > \endverbatim */
/* Arguments: */
/* ========== */
/* > \param[in] SIDE */
/* > \verbatim */
/* > SIDE is CHARACTER*1 */
/* > = 'R': compute right eigenvectors only; */
/* > = 'L': compute left eigenvectors only; */
/* > = 'B': compute both right and left eigenvectors. */
/* > \endverbatim */
/* > */
/* > \param[in] HOWMNY */
/* > \verbatim */
/* > HOWMNY is CHARACTER*1 */
/* > = 'A': compute all right and/or left eigenvectors; */
/* > = 'B': compute all right and/or left eigenvectors, */
/* > backtransformed by the matrices in VR and/or VL; */
/* > = 'S': compute selected right and/or left eigenvectors, */
/* > specified by the logical array SELECT. */
/* > \endverbatim */
/* > */
/* > \param[in] SELECT */
/* > \verbatim */
/* > SELECT is LOGICAL array, dimension (N) */
/* > If HOWMNY='S', SELECT specifies the eigenvectors to be */
/* > computed. The eigenvector corresponding to the j-th */
/* > eigenvalue is computed if SELECT(j) = .TRUE.. */
/* > Not referenced if HOWMNY = 'A' or 'B'. */
/* > \endverbatim */
/* > */
/* > \param[in] N */
/* > \verbatim */
/* > N is INTEGER */
/* > The order of the matrices S and P. N >= 0. */
/* > \endverbatim */
/* > */
/* > \param[in] S */
/* > \verbatim */
/* > S is COMPLEX*16 array, dimension (LDS,N) */
/* > The upper triangular matrix S from a generalized Schur */
/* > factorization, as computed by ZHGEQZ. */
/* > \endverbatim */
/* > */
/* > \param[in] LDS */
/* > \verbatim */
/* > LDS is INTEGER */
/* > The leading dimension of array S. LDS >= f2cmax(1,N). */
/* > \endverbatim */
/* > */
/* > \param[in] P */
/* > \verbatim */
/* > P is COMPLEX*16 array, dimension (LDP,N) */
/* > The upper triangular matrix P from a generalized Schur */
/* > factorization, as computed by ZHGEQZ. P must have real */
/* > diagonal elements. */
/* > \endverbatim */
/* > */
/* > \param[in] LDP */
/* > \verbatim */
/* > LDP is INTEGER */
/* > The leading dimension of array P. LDP >= f2cmax(1,N). */
/* > \endverbatim */
/* > */
/* > \param[in,out] VL */
/* > \verbatim */
/* > VL is COMPLEX*16 array, dimension (LDVL,MM) */
/* > On entry, if SIDE = 'L' or 'B' and HOWMNY = 'B', VL must */
/* > contain an N-by-N matrix Q (usually the unitary matrix Q */
/* > of left Schur vectors returned by ZHGEQZ). */
/* > On exit, if SIDE = 'L' or 'B', VL contains: */
/* > if HOWMNY = 'A', the matrix Y of left eigenvectors of (S,P); */
/* > if HOWMNY = 'B', the matrix Q*Y; */
/* > if HOWMNY = 'S', the left eigenvectors of (S,P) specified by */
/* > SELECT, stored consecutively in the columns of */
/* > VL, in the same order as their eigenvalues. */
/* > Not referenced if SIDE = 'R'. */
/* > \endverbatim */
/* > */
/* > \param[in] LDVL */
/* > \verbatim */
/* > LDVL is INTEGER */
/* > The leading dimension of array VL. LDVL >= 1, and if */
/* > SIDE = 'L' or 'l' or 'B' or 'b', LDVL >= N. */
/* > \endverbatim */
/* > */
/* > \param[in,out] VR */
/* > \verbatim */
/* > VR is COMPLEX*16 array, dimension (LDVR,MM) */
/* > On entry, if SIDE = 'R' or 'B' and HOWMNY = 'B', VR must */
/* > contain an N-by-N matrix Q (usually the unitary matrix Z */
/* > of right Schur vectors returned by ZHGEQZ). */
/* > On exit, if SIDE = 'R' or 'B', VR contains: */
/* > if HOWMNY = 'A', the matrix X of right eigenvectors of (S,P); */
/* > if HOWMNY = 'B', the matrix Z*X; */
/* > if HOWMNY = 'S', the right eigenvectors of (S,P) specified by */
/* > SELECT, stored consecutively in the columns of */
/* > VR, in the same order as their eigenvalues. */
/* > Not referenced if SIDE = 'L'. */
/* > \endverbatim */
/* > */
/* > \param[in] LDVR */
/* > \verbatim */
/* > LDVR is INTEGER */
/* > The leading dimension of the array VR. LDVR >= 1, and if */
/* > SIDE = 'R' or 'B', LDVR >= N. */
/* > \endverbatim */
/* > */
/* > \param[in] MM */
/* > \verbatim */
/* > MM is INTEGER */
/* > The number of columns in the arrays VL and/or VR. MM >= M. */
/* > \endverbatim */
/* > */
/* > \param[out] M */
/* > \verbatim */
/* > M is INTEGER */
/* > The number of columns in the arrays VL and/or VR actually */
/* > used to store the eigenvectors. If HOWMNY = 'A' or 'B', M */
/* > is set to N. Each selected eigenvector occupies one column. */
/* > \endverbatim */
/* > */
/* > \param[out] WORK */
/* > \verbatim */
/* > WORK is COMPLEX*16 array, dimension (2*N) */
/* > \endverbatim */
/* > */
/* > \param[out] RWORK */
/* > \verbatim */
/* > RWORK is DOUBLE PRECISION array, dimension (2*N) */
/* > \endverbatim */
/* > */
/* > \param[out] INFO */
/* > \verbatim */
/* > INFO is INTEGER */
/* > = 0: successful exit. */
/* > < 0: if INFO = -i, the i-th argument had an illegal value. */
/* > \endverbatim */
/* Authors: */
/* ======== */
/* > \author Univ. of Tennessee */
/* > \author Univ. of California Berkeley */
/* > \author Univ. of Colorado Denver */
/* > \author NAG Ltd. */
/* > \date December 2016 */
/* > \ingroup complex16GEcomputational */
/* ===================================================================== */
/* Subroutine */ void ztgevc_(char *side, char *howmny, logical *select,
integer *n, doublecomplex *s, integer *lds, doublecomplex *p, integer
*ldp, doublecomplex *vl, integer *ldvl, doublecomplex *vr, integer *
ldvr, integer *mm, integer *m, doublecomplex *work, doublereal *rwork,
integer *info)
{
/* System generated locals */
integer p_dim1, p_offset, s_dim1, s_offset, vl_dim1, vl_offset, vr_dim1,
vr_offset, i__1, i__2, i__3, i__4, i__5;
doublereal d__1, d__2, d__3, d__4, d__5, d__6;
doublecomplex z__1, z__2, z__3, z__4;
/* Local variables */
integer ibeg, ieig, iend;
doublereal dmin__;
integer isrc;
doublereal temp;
doublecomplex suma, sumb;
doublereal xmax;
doublecomplex d__;
integer i__, j;
doublereal scale;
logical ilall;
integer iside;
doublereal sbeta;
extern logical lsame_(char *, char *);
doublereal small;
logical compl;
doublereal anorm, bnorm;
logical compr;
extern /* Subroutine */ void zgemv_(char *, integer *, integer *,
doublecomplex *, doublecomplex *, integer *, doublecomplex *,
integer *, doublecomplex *, doublecomplex *, integer *);
doublecomplex ca, cb;
extern /* Subroutine */ void dlabad_(doublereal *, doublereal *);
logical ilbbad;
doublereal acoefa;
integer je;
doublereal bcoefa, acoeff;
doublecomplex bcoeff;
logical ilback;
integer im;
doublereal ascale, bscale;
extern doublereal dlamch_(char *);
integer jr;
doublecomplex salpha;
doublereal safmin;
extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
doublereal bignum;
logical ilcomp;
extern /* Double Complex */ VOID zladiv_(doublecomplex *, doublecomplex *,
doublecomplex *);
integer ihwmny;
doublereal big;
logical lsa, lsb;
doublereal ulp;
doublecomplex sum;
/* -- LAPACK computational routine (version 3.7.0) -- */
/* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
/* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
/* December 2016 */
/* ===================================================================== */
/* Decode and Test the input parameters */
/* Parameter adjustments */
--select;
s_dim1 = *lds;
s_offset = 1 + s_dim1 * 1;
s -= s_offset;
p_dim1 = *ldp;
p_offset = 1 + p_dim1 * 1;
p -= p_offset;
vl_dim1 = *ldvl;
vl_offset = 1 + vl_dim1 * 1;
vl -= vl_offset;
vr_dim1 = *ldvr;
vr_offset = 1 + vr_dim1 * 1;
vr -= vr_offset;
--work;
--rwork;
/* Function Body */
if (lsame_(howmny, "A")) {
ihwmny = 1;
ilall = TRUE_;
ilback = FALSE_;
} else if (lsame_(howmny, "S")) {
ihwmny = 2;
ilall = FALSE_;
ilback = FALSE_;
} else if (lsame_(howmny, "B")) {
ihwmny = 3;
ilall = TRUE_;
ilback = TRUE_;
} else {
ihwmny = -1;
}
if (lsame_(side, "R")) {
iside = 1;
compl = FALSE_;
compr = TRUE_;
} else if (lsame_(side, "L")) {
iside = 2;
compl = TRUE_;
compr = FALSE_;
} else if (lsame_(side, "B")) {
iside = 3;
compl = TRUE_;
compr = TRUE_;
} else {
iside = -1;
}
*info = 0;
if (iside < 0) {
*info = -1;
} else if (ihwmny < 0) {
*info = -2;
} else if (*n < 0) {
*info = -4;
} else if (*lds < f2cmax(1,*n)) {
*info = -6;
} else if (*ldp < f2cmax(1,*n)) {
*info = -8;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZTGEVC", &i__1, (ftnlen)6);
return;
}
/* Count the number of eigenvectors */
if (! ilall) {
im = 0;
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
if (select[j]) {
++im;
}
/* L10: */
}
} else {
im = *n;
}
/* Check diagonal of B */
ilbbad = FALSE_;
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
if (d_imag(&p[j + j * p_dim1]) != 0.) {
ilbbad = TRUE_;
}
/* L20: */
}
if (ilbbad) {
*info = -7;
} else if (compl && *ldvl < *n || *ldvl < 1) {
*info = -10;
} else if (compr && *ldvr < *n || *ldvr < 1) {
*info = -12;
} else if (*mm < im) {
*info = -13;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZTGEVC", &i__1, (ftnlen)6);
return;
}
/* Quick return if possible */
*m = im;
if (*n == 0) {
return;
}
/* Machine Constants */
safmin = dlamch_("Safe minimum");
big = 1. / safmin;
dlabad_(&safmin, &big);
ulp = dlamch_("Epsilon") * dlamch_("Base");
small = safmin * *n / ulp;
big = 1. / small;
bignum = 1. / (safmin * *n);
/* Compute the 1-norm of each column of the strictly upper triangular */
/* part of A and B to check for possible overflow in the triangular */
/* solver. */
i__1 = s_dim1 + 1;
anorm = (d__1 = s[i__1].r, abs(d__1)) + (d__2 = d_imag(&s[s_dim1 + 1]),
abs(d__2));
i__1 = p_dim1 + 1;
bnorm = (d__1 = p[i__1].r, abs(d__1)) + (d__2 = d_imag(&p[p_dim1 + 1]),
abs(d__2));
rwork[1] = 0.;
rwork[*n + 1] = 0.;
i__1 = *n;
for (j = 2; j <= i__1; ++j) {
rwork[j] = 0.;
rwork[*n + j] = 0.;
i__2 = j - 1;
for (i__ = 1; i__ <= i__2; ++i__) {
i__3 = i__ + j * s_dim1;
rwork[j] += (d__1 = s[i__3].r, abs(d__1)) + (d__2 = d_imag(&s[i__
+ j * s_dim1]), abs(d__2));
i__3 = i__ + j * p_dim1;
rwork[*n + j] += (d__1 = p[i__3].r, abs(d__1)) + (d__2 = d_imag(&
p[i__ + j * p_dim1]), abs(d__2));
/* L30: */
}
/* Computing MAX */
i__2 = j + j * s_dim1;
d__3 = anorm, d__4 = rwork[j] + ((d__1 = s[i__2].r, abs(d__1)) + (
d__2 = d_imag(&s[j + j * s_dim1]), abs(d__2)));
anorm = f2cmax(d__3,d__4);
/* Computing MAX */
i__2 = j + j * p_dim1;
d__3 = bnorm, d__4 = rwork[*n + j] + ((d__1 = p[i__2].r, abs(d__1)) +
(d__2 = d_imag(&p[j + j * p_dim1]), abs(d__2)));
bnorm = f2cmax(d__3,d__4);
/* L40: */
}
ascale = 1. / f2cmax(anorm,safmin);
bscale = 1. / f2cmax(bnorm,safmin);
/* Left eigenvectors */
if (compl) {
ieig = 0;
/* Main loop over eigenvalues */
i__1 = *n;
for (je = 1; je <= i__1; ++je) {
if (ilall) {
ilcomp = TRUE_;
} else {
ilcomp = select[je];
}
if (ilcomp) {
++ieig;
i__2 = je + je * s_dim1;
i__3 = je + je * p_dim1;
if ((d__2 = s[i__2].r, abs(d__2)) + (d__3 = d_imag(&s[je + je
* s_dim1]), abs(d__3)) <= safmin && (d__1 = p[i__3].r,
abs(d__1)) <= safmin) {
/* Singular matrix pencil -- return unit eigenvector */
i__2 = *n;
for (jr = 1; jr <= i__2; ++jr) {
i__3 = jr + ieig * vl_dim1;
vl[i__3].r = 0., vl[i__3].i = 0.;
/* L50: */
}
i__2 = ieig + ieig * vl_dim1;
vl[i__2].r = 1., vl[i__2].i = 0.;
goto L140;
}
/* Non-singular eigenvalue: */
/* Compute coefficients a and b in */
/* H */
/* y ( a A - b B ) = 0 */
/* Computing MAX */
i__2 = je + je * s_dim1;
i__3 = je + je * p_dim1;
d__4 = ((d__2 = s[i__2].r, abs(d__2)) + (d__3 = d_imag(&s[je
+ je * s_dim1]), abs(d__3))) * ascale, d__5 = (d__1 =
p[i__3].r, abs(d__1)) * bscale, d__4 = f2cmax(d__4,d__5);
temp = 1. / f2cmax(d__4,safmin);
i__2 = je + je * s_dim1;
z__2.r = temp * s[i__2].r, z__2.i = temp * s[i__2].i;
z__1.r = ascale * z__2.r, z__1.i = ascale * z__2.i;
salpha.r = z__1.r, salpha.i = z__1.i;
i__2 = je + je * p_dim1;
sbeta = temp * p[i__2].r * bscale;
acoeff = sbeta * ascale;
z__1.r = bscale * salpha.r, z__1.i = bscale * salpha.i;
bcoeff.r = z__1.r, bcoeff.i = z__1.i;
/* Scale to avoid underflow */
lsa = abs(sbeta) >= safmin && abs(acoeff) < small;
lsb = (d__1 = salpha.r, abs(d__1)) + (d__2 = d_imag(&salpha),
abs(d__2)) >= safmin && (d__3 = bcoeff.r, abs(d__3))
+ (d__4 = d_imag(&bcoeff), abs(d__4)) < small;
scale = 1.;
if (lsa) {
scale = small / abs(sbeta) * f2cmin(anorm,big);
}
if (lsb) {
/* Computing MAX */
d__3 = scale, d__4 = small / ((d__1 = salpha.r, abs(d__1))
+ (d__2 = d_imag(&salpha), abs(d__2))) * f2cmin(
bnorm,big);
scale = f2cmax(d__3,d__4);
}
if (lsa || lsb) {
/* Computing MIN */
/* Computing MAX */
d__5 = 1., d__6 = abs(acoeff), d__5 = f2cmax(d__5,d__6),
d__6 = (d__1 = bcoeff.r, abs(d__1)) + (d__2 =
d_imag(&bcoeff), abs(d__2));
d__3 = scale, d__4 = 1. / (safmin * f2cmax(d__5,d__6));
scale = f2cmin(d__3,d__4);
if (lsa) {
acoeff = ascale * (scale * sbeta);
} else {
acoeff = scale * acoeff;
}
if (lsb) {
z__2.r = scale * salpha.r, z__2.i = scale * salpha.i;
z__1.r = bscale * z__2.r, z__1.i = bscale * z__2.i;
bcoeff.r = z__1.r, bcoeff.i = z__1.i;
} else {
z__1.r = scale * bcoeff.r, z__1.i = scale * bcoeff.i;
bcoeff.r = z__1.r, bcoeff.i = z__1.i;
}
}
acoefa = abs(acoeff);
bcoefa = (d__1 = bcoeff.r, abs(d__1)) + (d__2 = d_imag(&
bcoeff), abs(d__2));
xmax = 1.;
i__2 = *n;
for (jr = 1; jr <= i__2; ++jr) {
i__3 = jr;
work[i__3].r = 0., work[i__3].i = 0.;
/* L60: */
}
i__2 = je;
work[i__2].r = 1., work[i__2].i = 0.;
/* Computing MAX */
d__1 = ulp * acoefa * anorm, d__2 = ulp * bcoefa * bnorm,
d__1 = f2cmax(d__1,d__2);
dmin__ = f2cmax(d__1,safmin);
/* H */
/* Triangular solve of (a A - b B) y = 0 */
/* H */
/* (rowwise in (a A - b B) , or columnwise in a A - b B) */
i__2 = *n;
for (j = je + 1; j <= i__2; ++j) {
/* Compute */
/* j-1 */
/* SUM = sum conjg( a*S(k,j) - b*P(k,j) )*x(k) */
/* k=je */
/* (Scale if necessary) */
temp = 1. / xmax;
if (acoefa * rwork[j] + bcoefa * rwork[*n + j] > bignum *
temp) {
i__3 = j - 1;
for (jr = je; jr <= i__3; ++jr) {
i__4 = jr;
i__5 = jr;
z__1.r = temp * work[i__5].r, z__1.i = temp *
work[i__5].i;
work[i__4].r = z__1.r, work[i__4].i = z__1.i;
/* L70: */
}
xmax = 1.;
}
suma.r = 0., suma.i = 0.;
sumb.r = 0., sumb.i = 0.;
i__3 = j - 1;
for (jr = je; jr <= i__3; ++jr) {
d_cnjg(&z__3, &s[jr + j * s_dim1]);
i__4 = jr;
z__2.r = z__3.r * work[i__4].r - z__3.i * work[i__4]
.i, z__2.i = z__3.r * work[i__4].i + z__3.i *
work[i__4].r;
z__1.r = suma.r + z__2.r, z__1.i = suma.i + z__2.i;
suma.r = z__1.r, suma.i = z__1.i;
d_cnjg(&z__3, &p[jr + j * p_dim1]);
i__4 = jr;
z__2.r = z__3.r * work[i__4].r - z__3.i * work[i__4]
.i, z__2.i = z__3.r * work[i__4].i + z__3.i *
work[i__4].r;
z__1.r = sumb.r + z__2.r, z__1.i = sumb.i + z__2.i;
sumb.r = z__1.r, sumb.i = z__1.i;
/* L80: */
}
z__2.r = acoeff * suma.r, z__2.i = acoeff * suma.i;
d_cnjg(&z__4, &bcoeff);
z__3.r = z__4.r * sumb.r - z__4.i * sumb.i, z__3.i =
z__4.r * sumb.i + z__4.i * sumb.r;
z__1.r = z__2.r - z__3.r, z__1.i = z__2.i - z__3.i;
sum.r = z__1.r, sum.i = z__1.i;
/* Form x(j) = - SUM / conjg( a*S(j,j) - b*P(j,j) ) */
/* with scaling and perturbation of the denominator */
i__3 = j + j * s_dim1;
z__3.r = acoeff * s[i__3].r, z__3.i = acoeff * s[i__3].i;
i__4 = j + j * p_dim1;
z__4.r = bcoeff.r * p[i__4].r - bcoeff.i * p[i__4].i,
z__4.i = bcoeff.r * p[i__4].i + bcoeff.i * p[i__4]
.r;
z__2.r = z__3.r - z__4.r, z__2.i = z__3.i - z__4.i;
d_cnjg(&z__1, &z__2);
d__.r = z__1.r, d__.i = z__1.i;
if ((d__1 = d__.r, abs(d__1)) + (d__2 = d_imag(&d__), abs(
d__2)) <= dmin__) {
z__1.r = dmin__, z__1.i = 0.;
d__.r = z__1.r, d__.i = z__1.i;
}
if ((d__1 = d__.r, abs(d__1)) + (d__2 = d_imag(&d__), abs(
d__2)) < 1.) {
if ((d__1 = sum.r, abs(d__1)) + (d__2 = d_imag(&sum),
abs(d__2)) >= bignum * ((d__3 = d__.r, abs(
d__3)) + (d__4 = d_imag(&d__), abs(d__4)))) {
temp = 1. / ((d__1 = sum.r, abs(d__1)) + (d__2 =
d_imag(&sum), abs(d__2)));
i__3 = j - 1;
for (jr = je; jr <= i__3; ++jr) {
i__4 = jr;
i__5 = jr;
z__1.r = temp * work[i__5].r, z__1.i = temp *
work[i__5].i;
work[i__4].r = z__1.r, work[i__4].i = z__1.i;
/* L90: */
}
xmax = temp * xmax;
z__1.r = temp * sum.r, z__1.i = temp * sum.i;
sum.r = z__1.r, sum.i = z__1.i;
}
}
i__3 = j;
z__2.r = -sum.r, z__2.i = -sum.i;
zladiv_(&z__1, &z__2, &d__);
work[i__3].r = z__1.r, work[i__3].i = z__1.i;
/* Computing MAX */
i__3 = j;
d__3 = xmax, d__4 = (d__1 = work[i__3].r, abs(d__1)) + (
d__2 = d_imag(&work[j]), abs(d__2));
xmax = f2cmax(d__3,d__4);
/* L100: */
}
/* Back transform eigenvector if HOWMNY='B'. */
if (ilback) {
i__2 = *n + 1 - je;
zgemv_("N", n, &i__2, &c_b2, &vl[je * vl_dim1 + 1], ldvl,
&work[je], &c__1, &c_b1, &work[*n + 1], &c__1);
isrc = 2;
ibeg = 1;
} else {
isrc = 1;
ibeg = je;
}
/* Copy and scale eigenvector into column of VL */
xmax = 0.;
i__2 = *n;
for (jr = ibeg; jr <= i__2; ++jr) {
/* Computing MAX */
i__3 = (isrc - 1) * *n + jr;
d__3 = xmax, d__4 = (d__1 = work[i__3].r, abs(d__1)) + (
d__2 = d_imag(&work[(isrc - 1) * *n + jr]), abs(
d__2));
xmax = f2cmax(d__3,d__4);
/* L110: */
}
if (xmax > safmin) {
temp = 1. / xmax;
i__2 = *n;
for (jr = ibeg; jr <= i__2; ++jr) {
i__3 = jr + ieig * vl_dim1;
i__4 = (isrc - 1) * *n + jr;
z__1.r = temp * work[i__4].r, z__1.i = temp * work[
i__4].i;
vl[i__3].r = z__1.r, vl[i__3].i = z__1.i;
/* L120: */
}
} else {
ibeg = *n + 1;
}
i__2 = ibeg - 1;
for (jr = 1; jr <= i__2; ++jr) {
i__3 = jr + ieig * vl_dim1;
vl[i__3].r = 0., vl[i__3].i = 0.;
/* L130: */
}
}
L140:
;
}
}
/* Right eigenvectors */
if (compr) {
ieig = im + 1;
/* Main loop over eigenvalues */
for (je = *n; je >= 1; --je) {
if (ilall) {
ilcomp = TRUE_;
} else {
ilcomp = select[je];
}
if (ilcomp) {
--ieig;
i__1 = je + je * s_dim1;
i__2 = je + je * p_dim1;
if ((d__2 = s[i__1].r, abs(d__2)) + (d__3 = d_imag(&s[je + je
* s_dim1]), abs(d__3)) <= safmin && (d__1 = p[i__2].r,
abs(d__1)) <= safmin) {
/* Singular matrix pencil -- return unit eigenvector */
i__1 = *n;
for (jr = 1; jr <= i__1; ++jr) {
i__2 = jr + ieig * vr_dim1;
vr[i__2].r = 0., vr[i__2].i = 0.;
/* L150: */
}
i__1 = ieig + ieig * vr_dim1;
vr[i__1].r = 1., vr[i__1].i = 0.;
goto L250;
}
/* Non-singular eigenvalue: */
/* Compute coefficients a and b in */
/* ( a A - b B ) x = 0 */
/* Computing MAX */
i__1 = je + je * s_dim1;
i__2 = je + je * p_dim1;
d__4 = ((d__2 = s[i__1].r, abs(d__2)) + (d__3 = d_imag(&s[je
+ je * s_dim1]), abs(d__3))) * ascale, d__5 = (d__1 =
p[i__2].r, abs(d__1)) * bscale, d__4 = f2cmax(d__4,d__5);
temp = 1. / f2cmax(d__4,safmin);
i__1 = je + je * s_dim1;
z__2.r = temp * s[i__1].r, z__2.i = temp * s[i__1].i;
z__1.r = ascale * z__2.r, z__1.i = ascale * z__2.i;
salpha.r = z__1.r, salpha.i = z__1.i;
i__1 = je + je * p_dim1;
sbeta = temp * p[i__1].r * bscale;
acoeff = sbeta * ascale;
z__1.r = bscale * salpha.r, z__1.i = bscale * salpha.i;
bcoeff.r = z__1.r, bcoeff.i = z__1.i;
/* Scale to avoid underflow */
lsa = abs(sbeta) >= safmin && abs(acoeff) < small;
lsb = (d__1 = salpha.r, abs(d__1)) + (d__2 = d_imag(&salpha),
abs(d__2)) >= safmin && (d__3 = bcoeff.r, abs(d__3))
+ (d__4 = d_imag(&bcoeff), abs(d__4)) < small;
scale = 1.;
if (lsa) {
scale = small / abs(sbeta) * f2cmin(anorm,big);
}
if (lsb) {
/* Computing MAX */
d__3 = scale, d__4 = small / ((d__1 = salpha.r, abs(d__1))
+ (d__2 = d_imag(&salpha), abs(d__2))) * f2cmin(
bnorm,big);
scale = f2cmax(d__3,d__4);
}
if (lsa || lsb) {
/* Computing MIN */
/* Computing MAX */
d__5 = 1., d__6 = abs(acoeff), d__5 = f2cmax(d__5,d__6),
d__6 = (d__1 = bcoeff.r, abs(d__1)) + (d__2 =
d_imag(&bcoeff), abs(d__2));
d__3 = scale, d__4 = 1. / (safmin * f2cmax(d__5,d__6));
scale = f2cmin(d__3,d__4);
if (lsa) {
acoeff = ascale * (scale * sbeta);
} else {
acoeff = scale * acoeff;
}
if (lsb) {
z__2.r = scale * salpha.r, z__2.i = scale * salpha.i;
z__1.r = bscale * z__2.r, z__1.i = bscale * z__2.i;
bcoeff.r = z__1.r, bcoeff.i = z__1.i;
} else {
z__1.r = scale * bcoeff.r, z__1.i = scale * bcoeff.i;
bcoeff.r = z__1.r, bcoeff.i = z__1.i;
}
}
acoefa = abs(acoeff);
bcoefa = (d__1 = bcoeff.r, abs(d__1)) + (d__2 = d_imag(&
bcoeff), abs(d__2));
xmax = 1.;
i__1 = *n;
for (jr = 1; jr <= i__1; ++jr) {
i__2 = jr;
work[i__2].r = 0., work[i__2].i = 0.;
/* L160: */
}
i__1 = je;
work[i__1].r = 1., work[i__1].i = 0.;
/* Computing MAX */
d__1 = ulp * acoefa * anorm, d__2 = ulp * bcoefa * bnorm,
d__1 = f2cmax(d__1,d__2);
dmin__ = f2cmax(d__1,safmin);
/* Triangular solve of (a A - b B) x = 0 (columnwise) */
/* WORK(1:j-1) contains sums w, */
/* WORK(j+1:JE) contains x */
i__1 = je - 1;
for (jr = 1; jr <= i__1; ++jr) {
i__2 = jr;
i__3 = jr + je * s_dim1;
z__2.r = acoeff * s[i__3].r, z__2.i = acoeff * s[i__3].i;
i__4 = jr + je * p_dim1;
z__3.r = bcoeff.r * p[i__4].r - bcoeff.i * p[i__4].i,
z__3.i = bcoeff.r * p[i__4].i + bcoeff.i * p[i__4]
.r;
z__1.r = z__2.r - z__3.r, z__1.i = z__2.i - z__3.i;
work[i__2].r = z__1.r, work[i__2].i = z__1.i;
/* L170: */
}
i__1 = je;
work[i__1].r = 1., work[i__1].i = 0.;
for (j = je - 1; j >= 1; --j) {
/* Form x(j) := - w(j) / d */
/* with scaling and perturbation of the denominator */
i__1 = j + j * s_dim1;
z__2.r = acoeff * s[i__1].r, z__2.i = acoeff * s[i__1].i;
i__2 = j + j * p_dim1;
z__3.r = bcoeff.r * p[i__2].r - bcoeff.i * p[i__2].i,
z__3.i = bcoeff.r * p[i__2].i + bcoeff.i * p[i__2]
.r;
z__1.r = z__2.r - z__3.r, z__1.i = z__2.i - z__3.i;
d__.r = z__1.r, d__.i = z__1.i;
if ((d__1 = d__.r, abs(d__1)) + (d__2 = d_imag(&d__), abs(
d__2)) <= dmin__) {
z__1.r = dmin__, z__1.i = 0.;
d__.r = z__1.r, d__.i = z__1.i;
}
if ((d__1 = d__.r, abs(d__1)) + (d__2 = d_imag(&d__), abs(
d__2)) < 1.) {
i__1 = j;
if ((d__1 = work[i__1].r, abs(d__1)) + (d__2 = d_imag(
&work[j]), abs(d__2)) >= bignum * ((d__3 =
d__.r, abs(d__3)) + (d__4 = d_imag(&d__), abs(
d__4)))) {
i__1 = j;
temp = 1. / ((d__1 = work[i__1].r, abs(d__1)) + (
d__2 = d_imag(&work[j]), abs(d__2)));
i__1 = je;
for (jr = 1; jr <= i__1; ++jr) {
i__2 = jr;
i__3 = jr;
z__1.r = temp * work[i__3].r, z__1.i = temp *
work[i__3].i;
work[i__2].r = z__1.r, work[i__2].i = z__1.i;
/* L180: */
}
}
}
i__1 = j;
i__2 = j;
z__2.r = -work[i__2].r, z__2.i = -work[i__2].i;
zladiv_(&z__1, &z__2, &d__);
work[i__1].r = z__1.r, work[i__1].i = z__1.i;
if (j > 1) {
/* w = w + x(j)*(a S(*,j) - b P(*,j) ) with scaling */
i__1 = j;
if ((d__1 = work[i__1].r, abs(d__1)) + (d__2 = d_imag(
&work[j]), abs(d__2)) > 1.) {
i__1 = j;
temp = 1. / ((d__1 = work[i__1].r, abs(d__1)) + (
d__2 = d_imag(&work[j]), abs(d__2)));
if (acoefa * rwork[j] + bcoefa * rwork[*n + j] >=
bignum * temp) {
i__1 = je;
for (jr = 1; jr <= i__1; ++jr) {
i__2 = jr;
i__3 = jr;
z__1.r = temp * work[i__3].r, z__1.i =
temp * work[i__3].i;
work[i__2].r = z__1.r, work[i__2].i =
z__1.i;
/* L190: */
}
}
}
i__1 = j;
z__1.r = acoeff * work[i__1].r, z__1.i = acoeff *
work[i__1].i;
ca.r = z__1.r, ca.i = z__1.i;
i__1 = j;
z__1.r = bcoeff.r * work[i__1].r - bcoeff.i * work[
i__1].i, z__1.i = bcoeff.r * work[i__1].i +
bcoeff.i * work[i__1].r;
cb.r = z__1.r, cb.i = z__1.i;
i__1 = j - 1;
for (jr = 1; jr <= i__1; ++jr) {
i__2 = jr;
i__3 = jr;
i__4 = jr + j * s_dim1;
z__3.r = ca.r * s[i__4].r - ca.i * s[i__4].i,
z__3.i = ca.r * s[i__4].i + ca.i * s[i__4]
.r;
z__2.r = work[i__3].r + z__3.r, z__2.i = work[
i__3].i + z__3.i;
i__5 = jr + j * p_dim1;
z__4.r = cb.r * p[i__5].r - cb.i * p[i__5].i,
z__4.i = cb.r * p[i__5].i + cb.i * p[i__5]
.r;
z__1.r = z__2.r - z__4.r, z__1.i = z__2.i -
z__4.i;
work[i__2].r = z__1.r, work[i__2].i = z__1.i;
/* L200: */
}
}
/* L210: */
}
/* Back transform eigenvector if HOWMNY='B'. */
if (ilback) {
zgemv_("N", n, &je, &c_b2, &vr[vr_offset], ldvr, &work[1],
&c__1, &c_b1, &work[*n + 1], &c__1);
isrc = 2;
iend = *n;
} else {
isrc = 1;
iend = je;
}
/* Copy and scale eigenvector into column of VR */
xmax = 0.;
i__1 = iend;
for (jr = 1; jr <= i__1; ++jr) {
/* Computing MAX */
i__2 = (isrc - 1) * *n + jr;
d__3 = xmax, d__4 = (d__1 = work[i__2].r, abs(d__1)) + (
d__2 = d_imag(&work[(isrc - 1) * *n + jr]), abs(
d__2));
xmax = f2cmax(d__3,d__4);
/* L220: */
}
if (xmax > safmin) {
temp = 1. / xmax;
i__1 = iend;
for (jr = 1; jr <= i__1; ++jr) {
i__2 = jr + ieig * vr_dim1;
i__3 = (isrc - 1) * *n + jr;
z__1.r = temp * work[i__3].r, z__1.i = temp * work[
i__3].i;
vr[i__2].r = z__1.r, vr[i__2].i = z__1.i;
/* L230: */
}
} else {
iend = 0;
}
i__1 = *n;
for (jr = iend + 1; jr <= i__1; ++jr) {
i__2 = jr + ieig * vr_dim1;
vr[i__2].r = 0., vr[i__2].i = 0.;
/* L240: */
}
}
L250:
;
}
}
return;
/* End of ZTGEVC */
} /* ztgevc_ */