OpenBLAS/lapack-netlib/SRC/strsna.c

1191 lines
34 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]/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++ */
#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 integer c__1 = 1;
static logical c_true = TRUE_;
static logical c_false = FALSE_;
/* > \brief \b STRSNA */
/* =========== DOCUMENTATION =========== */
/* Online html documentation available at */
/* http://www.netlib.org/lapack/explore-html/ */
/* > \htmlonly */
/* > Download STRSNA + dependencies */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/strsna.
f"> */
/* > [TGZ]</a> */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/strsna.
f"> */
/* > [ZIP]</a> */
/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/strsna.
f"> */
/* > [TXT]</a> */
/* > \endhtmlonly */
/* Definition: */
/* =========== */
/* SUBROUTINE STRSNA( JOB, HOWMNY, SELECT, N, T, LDT, VL, LDVL, VR, */
/* LDVR, S, SEP, MM, M, WORK, LDWORK, IWORK, */
/* INFO ) */
/* CHARACTER HOWMNY, JOB */
/* INTEGER INFO, LDT, LDVL, LDVR, LDWORK, M, MM, N */
/* LOGICAL SELECT( * ) */
/* INTEGER IWORK( * ) */
/* REAL S( * ), SEP( * ), T( LDT, * ), VL( LDVL, * ), */
/* $ VR( LDVR, * ), WORK( LDWORK, * ) */
/* > \par Purpose: */
/* ============= */
/* > */
/* > \verbatim */
/* > */
/* > STRSNA estimates reciprocal condition numbers for specified */
/* > eigenvalues and/or right eigenvectors of a real upper */
/* > quasi-triangular matrix T (or of any matrix Q*T*Q**T with Q */
/* > orthogonal). */
/* > */
/* > T must be in Schur canonical form (as returned by SHSEQR), that is, */
/* > block upper triangular with 1-by-1 and 2-by-2 diagonal blocks; each */
/* > 2-by-2 diagonal block has its diagonal elements equal and its */
/* > off-diagonal elements of opposite sign. */
/* > \endverbatim */
/* Arguments: */
/* ========== */
/* > \param[in] JOB */
/* > \verbatim */
/* > JOB is CHARACTER*1 */
/* > Specifies whether condition numbers are required for */
/* > eigenvalues (S) or eigenvectors (SEP): */
/* > = 'E': for eigenvalues only (S); */
/* > = 'V': for eigenvectors only (SEP); */
/* > = 'B': for both eigenvalues and eigenvectors (S and SEP). */
/* > \endverbatim */
/* > */
/* > \param[in] HOWMNY */
/* > \verbatim */
/* > HOWMNY is CHARACTER*1 */
/* > = 'A': compute condition numbers for all eigenpairs; */
/* > = 'S': compute condition numbers for selected eigenpairs */
/* > specified by the array SELECT. */
/* > \endverbatim */
/* > */
/* > \param[in] SELECT */
/* > \verbatim */
/* > SELECT is LOGICAL array, dimension (N) */
/* > If HOWMNY = 'S', SELECT specifies the eigenpairs for which */
/* > condition numbers are required. To select condition numbers */
/* > for the eigenpair corresponding to a real eigenvalue w(j), */
/* > SELECT(j) must be set to .TRUE.. To select condition numbers */
/* > corresponding to a complex conjugate pair of eigenvalues w(j) */
/* > and w(j+1), either SELECT(j) or SELECT(j+1) or both, must be */
/* > set to .TRUE.. */
/* > If HOWMNY = 'A', SELECT is not referenced. */
/* > \endverbatim */
/* > */
/* > \param[in] N */
/* > \verbatim */
/* > N is INTEGER */
/* > The order of the matrix T. N >= 0. */
/* > \endverbatim */
/* > */
/* > \param[in] T */
/* > \verbatim */
/* > T is REAL array, dimension (LDT,N) */
/* > The upper quasi-triangular matrix T, in Schur canonical form. */
/* > \endverbatim */
/* > */
/* > \param[in] LDT */
/* > \verbatim */
/* > LDT is INTEGER */
/* > The leading dimension of the array T. LDT >= f2cmax(1,N). */
/* > \endverbatim */
/* > */
/* > \param[in] VL */
/* > \verbatim */
/* > VL is REAL array, dimension (LDVL,M) */
/* > If JOB = 'E' or 'B', VL must contain left eigenvectors of T */
/* > (or of any Q*T*Q**T with Q orthogonal), corresponding to the */
/* > eigenpairs specified by HOWMNY and SELECT. The eigenvectors */
/* > must be stored in consecutive columns of VL, as returned by */
/* > SHSEIN or STREVC. */
/* > If JOB = 'V', VL is not referenced. */
/* > \endverbatim */
/* > */
/* > \param[in] LDVL */
/* > \verbatim */
/* > LDVL is INTEGER */
/* > The leading dimension of the array VL. */
/* > LDVL >= 1; and if JOB = 'E' or 'B', LDVL >= N. */
/* > \endverbatim */
/* > */
/* > \param[in] VR */
/* > \verbatim */
/* > VR is REAL array, dimension (LDVR,M) */
/* > If JOB = 'E' or 'B', VR must contain right eigenvectors of T */
/* > (or of any Q*T*Q**T with Q orthogonal), corresponding to the */
/* > eigenpairs specified by HOWMNY and SELECT. The eigenvectors */
/* > must be stored in consecutive columns of VR, as returned by */
/* > SHSEIN or STREVC. */
/* > If JOB = 'V', VR is not referenced. */
/* > \endverbatim */
/* > */
/* > \param[in] LDVR */
/* > \verbatim */
/* > LDVR is INTEGER */
/* > The leading dimension of the array VR. */
/* > LDVR >= 1; and if JOB = 'E' or 'B', LDVR >= N. */
/* > \endverbatim */
/* > */
/* > \param[out] S */
/* > \verbatim */
/* > S is REAL array, dimension (MM) */
/* > If JOB = 'E' or 'B', the reciprocal condition numbers of the */
/* > selected eigenvalues, stored in consecutive elements of the */
/* > array. For a complex conjugate pair of eigenvalues two */
/* > consecutive elements of S are set to the same value. Thus */
/* > S(j), SEP(j), and the j-th columns of VL and VR all */
/* > correspond to the same eigenpair (but not in general the */
/* > j-th eigenpair, unless all eigenpairs are selected). */
/* > If JOB = 'V', S is not referenced. */
/* > \endverbatim */
/* > */
/* > \param[out] SEP */
/* > \verbatim */
/* > SEP is REAL array, dimension (MM) */
/* > If JOB = 'V' or 'B', the estimated reciprocal condition */
/* > numbers of the selected eigenvectors, stored in consecutive */
/* > elements of the array. For a complex eigenvector two */
/* > consecutive elements of SEP are set to the same value. If */
/* > the eigenvalues cannot be reordered to compute SEP(j), SEP(j) */
/* > is set to 0; this can only occur when the true value would be */
/* > very small anyway. */
/* > If JOB = 'E', SEP is not referenced. */
/* > \endverbatim */
/* > */
/* > \param[in] MM */
/* > \verbatim */
/* > MM is INTEGER */
/* > The number of elements in the arrays S (if JOB = 'E' or 'B') */
/* > and/or SEP (if JOB = 'V' or 'B'). MM >= M. */
/* > \endverbatim */
/* > */
/* > \param[out] M */
/* > \verbatim */
/* > M is INTEGER */
/* > The number of elements of the arrays S and/or SEP actually */
/* > used to store the estimated condition numbers. */
/* > If HOWMNY = 'A', M is set to N. */
/* > \endverbatim */
/* > */
/* > \param[out] WORK */
/* > \verbatim */
/* > WORK is REAL array, dimension (LDWORK,N+6) */
/* > If JOB = 'E', WORK is not referenced. */
/* > \endverbatim */
/* > */
/* > \param[in] LDWORK */
/* > \verbatim */
/* > LDWORK is INTEGER */
/* > The leading dimension of the array WORK. */
/* > LDWORK >= 1; and if JOB = 'V' or 'B', LDWORK >= N. */
/* > \endverbatim */
/* > */
/* > \param[out] IWORK */
/* > \verbatim */
/* > IWORK is INTEGER array, dimension (2*(N-1)) */
/* > If JOB = 'E', IWORK is not referenced. */
/* > \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 realOTHERcomputational */
/* > \par Further Details: */
/* ===================== */
/* > */
/* > \verbatim */
/* > */
/* > The reciprocal of the condition number of an eigenvalue lambda is */
/* > defined as */
/* > */
/* > S(lambda) = |v**T*u| / (norm(u)*norm(v)) */
/* > */
/* > where u and v are the right and left eigenvectors of T corresponding */
/* > to lambda; v**T denotes the transpose of v, and norm(u) */
/* > denotes the Euclidean norm. These reciprocal condition numbers always */
/* > lie between zero (very badly conditioned) and one (very well */
/* > conditioned). If n = 1, S(lambda) is defined to be 1. */
/* > */
/* > An approximate error bound for a computed eigenvalue W(i) is given by */
/* > */
/* > EPS * norm(T) / S(i) */
/* > */
/* > where EPS is the machine precision. */
/* > */
/* > The reciprocal of the condition number of the right eigenvector u */
/* > corresponding to lambda is defined as follows. Suppose */
/* > */
/* > T = ( lambda c ) */
/* > ( 0 T22 ) */
/* > */
/* > Then the reciprocal condition number is */
/* > */
/* > SEP( lambda, T22 ) = sigma-f2cmin( T22 - lambda*I ) */
/* > */
/* > where sigma-f2cmin denotes the smallest singular value. We approximate */
/* > the smallest singular value by the reciprocal of an estimate of the */
/* > one-norm of the inverse of T22 - lambda*I. If n = 1, SEP(1) is */
/* > defined to be abs(T(1,1)). */
/* > */
/* > An approximate error bound for a computed right eigenvector VR(i) */
/* > is given by */
/* > */
/* > EPS * norm(T) / SEP(i) */
/* > \endverbatim */
/* > */
/* ===================================================================== */
/* Subroutine */ void strsna_(char *job, char *howmny, logical *select,
integer *n, real *t, integer *ldt, real *vl, integer *ldvl, real *vr,
integer *ldvr, real *s, real *sep, integer *mm, integer *m, real *
work, integer *ldwork, integer *iwork, integer *info)
{
/* System generated locals */
integer t_dim1, t_offset, vl_dim1, vl_offset, vr_dim1, vr_offset,
work_dim1, work_offset, i__1, i__2;
real r__1, r__2;
/* Local variables */
integer kase;
real cond;
logical pair;
integer ierr;
real dumm, prod;
integer ifst;
real lnrm;
extern real sdot_(integer *, real *, integer *, real *, integer *);
integer ilst;
real rnrm, prod1, prod2;
extern real snrm2_(integer *, real *, integer *);
integer i__, j, k;
real scale, delta;
extern logical lsame_(char *, char *);
integer isave[3];
logical wants;
real dummy[1];
integer n2;
extern /* Subroutine */ void slacn2_(integer *, real *, real *, integer *,
real *, integer *, integer *);
extern real slapy2_(real *, real *);
real cs;
extern /* Subroutine */ void slabad_(real *, real *);
integer nn, ks;
real sn, mu;
extern real slamch_(char *);
extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
real bignum;
logical wantbh;
extern /* Subroutine */ void slacpy_(char *, integer *, integer *, real *,
integer *, real *, integer *);
logical somcon;
extern /* Subroutine */ void slaqtr_(logical *, logical *, integer *, real
*, integer *, real *, real *, real *, real *, real *, integer *),
strexc_(char *, integer *, real *, integer *, real *, integer *,
integer *, integer *, real *, integer *);
real smlnum;
logical wantsp;
real eps, est;
/* -- 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;
t_dim1 = *ldt;
t_offset = 1 + t_dim1 * 1;
t -= t_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;
--s;
--sep;
work_dim1 = *ldwork;
work_offset = 1 + work_dim1 * 1;
work -= work_offset;
--iwork;
/* Function Body */
wantbh = lsame_(job, "B");
wants = lsame_(job, "E") || wantbh;
wantsp = lsame_(job, "V") || wantbh;
somcon = lsame_(howmny, "S");
*info = 0;
if (! wants && ! wantsp) {
*info = -1;
} else if (! lsame_(howmny, "A") && ! somcon) {
*info = -2;
} else if (*n < 0) {
*info = -4;
} else if (*ldt < f2cmax(1,*n)) {
*info = -6;
} else if (*ldvl < 1 || wants && *ldvl < *n) {
*info = -8;
} else if (*ldvr < 1 || wants && *ldvr < *n) {
*info = -10;
} else {
/* Set M to the number of eigenpairs for which condition numbers */
/* are required, and test MM. */
if (somcon) {
*m = 0;
pair = FALSE_;
i__1 = *n;
for (k = 1; k <= i__1; ++k) {
if (pair) {
pair = FALSE_;
} else {
if (k < *n) {
if (t[k + 1 + k * t_dim1] == 0.f) {
if (select[k]) {
++(*m);
}
} else {
pair = TRUE_;
if (select[k] || select[k + 1]) {
*m += 2;
}
}
} else {
if (select[*n]) {
++(*m);
}
}
}
/* L10: */
}
} else {
*m = *n;
}
if (*mm < *m) {
*info = -13;
} else if (*ldwork < 1 || wantsp && *ldwork < *n) {
*info = -16;
}
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("STRSNA", &i__1, (ftnlen)6);
return;
}
/* Quick return if possible */
if (*n == 0) {
return;
}
if (*n == 1) {
if (somcon) {
if (! select[1]) {
return;
}
}
if (wants) {
s[1] = 1.f;
}
if (wantsp) {
sep[1] = (r__1 = t[t_dim1 + 1], abs(r__1));
}
return;
}
/* Get machine constants */
eps = slamch_("P");
smlnum = slamch_("S") / eps;
bignum = 1.f / smlnum;
slabad_(&smlnum, &bignum);
ks = 0;
pair = FALSE_;
i__1 = *n;
for (k = 1; k <= i__1; ++k) {
/* Determine whether T(k,k) begins a 1-by-1 or 2-by-2 block. */
if (pair) {
pair = FALSE_;
goto L60;
} else {
if (k < *n) {
pair = t[k + 1 + k * t_dim1] != 0.f;
}
}
/* Determine whether condition numbers are required for the k-th */
/* eigenpair. */
if (somcon) {
if (pair) {
if (! select[k] && ! select[k + 1]) {
goto L60;
}
} else {
if (! select[k]) {
goto L60;
}
}
}
++ks;
if (wants) {
/* Compute the reciprocal condition number of the k-th */
/* eigenvalue. */
if (! pair) {
/* Real eigenvalue. */
prod = sdot_(n, &vr[ks * vr_dim1 + 1], &c__1, &vl[ks *
vl_dim1 + 1], &c__1);
rnrm = snrm2_(n, &vr[ks * vr_dim1 + 1], &c__1);
lnrm = snrm2_(n, &vl[ks * vl_dim1 + 1], &c__1);
s[ks] = abs(prod) / (rnrm * lnrm);
} else {
/* Complex eigenvalue. */
prod1 = sdot_(n, &vr[ks * vr_dim1 + 1], &c__1, &vl[ks *
vl_dim1 + 1], &c__1);
prod1 += sdot_(n, &vr[(ks + 1) * vr_dim1 + 1], &c__1, &vl[(ks
+ 1) * vl_dim1 + 1], &c__1);
prod2 = sdot_(n, &vl[ks * vl_dim1 + 1], &c__1, &vr[(ks + 1) *
vr_dim1 + 1], &c__1);
prod2 -= sdot_(n, &vl[(ks + 1) * vl_dim1 + 1], &c__1, &vr[ks *
vr_dim1 + 1], &c__1);
r__1 = snrm2_(n, &vr[ks * vr_dim1 + 1], &c__1);
r__2 = snrm2_(n, &vr[(ks + 1) * vr_dim1 + 1], &c__1);
rnrm = slapy2_(&r__1, &r__2);
r__1 = snrm2_(n, &vl[ks * vl_dim1 + 1], &c__1);
r__2 = snrm2_(n, &vl[(ks + 1) * vl_dim1 + 1], &c__1);
lnrm = slapy2_(&r__1, &r__2);
cond = slapy2_(&prod1, &prod2) / (rnrm * lnrm);
s[ks] = cond;
s[ks + 1] = cond;
}
}
if (wantsp) {
/* Estimate the reciprocal condition number of the k-th */
/* eigenvector. */
/* Copy the matrix T to the array WORK and swap the diagonal */
/* block beginning at T(k,k) to the (1,1) position. */
slacpy_("Full", n, n, &t[t_offset], ldt, &work[work_offset],
ldwork);
ifst = k;
ilst = 1;
strexc_("No Q", n, &work[work_offset], ldwork, dummy, &c__1, &
ifst, &ilst, &work[(*n + 1) * work_dim1 + 1], &ierr);
if (ierr == 1 || ierr == 2) {
/* Could not swap because blocks not well separated */
scale = 1.f;
est = bignum;
} else {
/* Reordering successful */
if (work[work_dim1 + 2] == 0.f) {
/* Form C = T22 - lambda*I in WORK(2:N,2:N). */
i__2 = *n;
for (i__ = 2; i__ <= i__2; ++i__) {
work[i__ + i__ * work_dim1] -= work[work_dim1 + 1];
/* L20: */
}
n2 = 1;
nn = *n - 1;
} else {
/* Triangularize the 2 by 2 block by unitary */
/* transformation U = [ cs i*ss ] */
/* [ i*ss cs ]. */
/* such that the (1,1) position of WORK is complex */
/* eigenvalue lambda with positive imaginary part. (2,2) */
/* position of WORK is the complex eigenvalue lambda */
/* with negative imaginary part. */
mu = sqrt((r__1 = work[(work_dim1 << 1) + 1], abs(r__1)))
* sqrt((r__2 = work[work_dim1 + 2], abs(r__2)));
delta = slapy2_(&mu, &work[work_dim1 + 2]);
cs = mu / delta;
sn = -work[work_dim1 + 2] / delta;
/* Form */
/* C**T = WORK(2:N,2:N) + i*[rwork(1) ..... rwork(n-1) ] */
/* [ mu ] */
/* [ .. ] */
/* [ .. ] */
/* [ mu ] */
/* where C**T is transpose of matrix C, */
/* and RWORK is stored starting in the N+1-st column of */
/* WORK. */
i__2 = *n;
for (j = 3; j <= i__2; ++j) {
work[j * work_dim1 + 2] = cs * work[j * work_dim1 + 2]
;
work[j + j * work_dim1] -= work[work_dim1 + 1];
/* L30: */
}
work[(work_dim1 << 1) + 2] = 0.f;
work[(*n + 1) * work_dim1 + 1] = mu * 2.f;
i__2 = *n - 1;
for (i__ = 2; i__ <= i__2; ++i__) {
work[i__ + (*n + 1) * work_dim1] = sn * work[(i__ + 1)
* work_dim1 + 1];
/* L40: */
}
n2 = 2;
nn = *n - 1 << 1;
}
/* Estimate norm(inv(C**T)) */
est = 0.f;
kase = 0;
L50:
slacn2_(&nn, &work[(*n + 2) * work_dim1 + 1], &work[(*n + 4) *
work_dim1 + 1], &iwork[1], &est, &kase, isave);
if (kase != 0) {
if (kase == 1) {
if (n2 == 1) {
/* Real eigenvalue: solve C**T*x = scale*c. */
i__2 = *n - 1;
slaqtr_(&c_true, &c_true, &i__2, &work[(work_dim1
<< 1) + 2], ldwork, dummy, &dumm, &scale,
&work[(*n + 4) * work_dim1 + 1], &work[(*
n + 6) * work_dim1 + 1], &ierr);
} else {
/* Complex eigenvalue: solve */
/* C**T*(p+iq) = scale*(c+id) in real arithmetic. */
i__2 = *n - 1;
slaqtr_(&c_true, &c_false, &i__2, &work[(
work_dim1 << 1) + 2], ldwork, &work[(*n +
1) * work_dim1 + 1], &mu, &scale, &work[(*
n + 4) * work_dim1 + 1], &work[(*n + 6) *
work_dim1 + 1], &ierr);
}
} else {
if (n2 == 1) {
/* Real eigenvalue: solve C*x = scale*c. */
i__2 = *n - 1;
slaqtr_(&c_false, &c_true, &i__2, &work[(
work_dim1 << 1) + 2], ldwork, dummy, &
dumm, &scale, &work[(*n + 4) * work_dim1
+ 1], &work[(*n + 6) * work_dim1 + 1], &
ierr);
} else {
/* Complex eigenvalue: solve */
/* C*(p+iq) = scale*(c+id) in real arithmetic. */
i__2 = *n - 1;
slaqtr_(&c_false, &c_false, &i__2, &work[(
work_dim1 << 1) + 2], ldwork, &work[(*n +
1) * work_dim1 + 1], &mu, &scale, &work[(*
n + 4) * work_dim1 + 1], &work[(*n + 6) *
work_dim1 + 1], &ierr);
}
}
goto L50;
}
}
sep[ks] = scale / f2cmax(est,smlnum);
if (pair) {
sep[ks + 1] = sep[ks];
}
}
if (pair) {
++ks;
}
L60:
;
}
return;
/* End of STRSNA */
} /* strsna_ */