14 typedef long long BLASLONG;
15 typedef unsigned long long BLASULONG;
17 typedef long BLASLONG;
18 typedef unsigned long BLASULONG;
22 typedef BLASLONG blasint;
24 #define blasabs(x) llabs(x)
26 #define blasabs(x) labs(x)
30 #define blasabs(x) abs(x)
33 typedef blasint integer;
35 typedef unsigned int uinteger;
36 typedef char *address;
37 typedef short int shortint;
39 typedef double doublereal;
40 typedef struct { real r, i; } complex;
41 typedef struct { doublereal r, i; } doublecomplex;
43 static inline _Fcomplex Cf(complex *z) {_Fcomplex zz={z->r , z->i}; return zz;}
44 static inline _Dcomplex Cd(doublecomplex *z) {_Dcomplex zz={z->r , z->i};return zz;}
45 static inline _Fcomplex * _pCf(complex *z) {return (_Fcomplex*)z;}
46 static inline _Dcomplex * _pCd(doublecomplex *z) {return (_Dcomplex*)z;}
48 static inline _Complex float Cf(complex *z) {return z->r + z->i*_Complex_I;}
49 static inline _Complex double Cd(doublecomplex *z) {return z->r + z->i*_Complex_I;}
50 static inline _Complex float * _pCf(complex *z) {return (_Complex float*)z;}
51 static inline _Complex double * _pCd(doublecomplex *z) {return (_Complex double*)z;}
53 #define pCf(z) (*_pCf(z))
54 #define pCd(z) (*_pCd(z))
56 typedef short int shortlogical;
57 typedef char logical1;
58 typedef char integer1;
63 /* Extern is for use with -E */
74 /*external read, write*/
83 /*internal read, write*/
113 /*rewind, backspace, endfile*/
125 ftnint *inex; /*parameters in standard's order*/
151 union Multitype { /* for multiple entry points */
162 typedef union Multitype Multitype;
164 struct Vardesc { /* for Namelist */
170 typedef struct Vardesc Vardesc;
177 typedef struct Namelist Namelist;
179 #define abs(x) ((x) >= 0 ? (x) : -(x))
180 #define dabs(x) (fabs(x))
181 #define f2cmin(a,b) ((a) <= (b) ? (a) : (b))
182 #define f2cmax(a,b) ((a) >= (b) ? (a) : (b))
183 #define dmin(a,b) (f2cmin(a,b))
184 #define dmax(a,b) (f2cmax(a,b))
185 #define bit_test(a,b) ((a) >> (b) & 1)
186 #define bit_clear(a,b) ((a) & ~((uinteger)1 << (b)))
187 #define bit_set(a,b) ((a) | ((uinteger)1 << (b)))
189 #define abort_() { sig_die("Fortran abort routine called", 1); }
190 #define c_abs(z) (cabsf(Cf(z)))
191 #define c_cos(R,Z) { pCf(R)=ccos(Cf(Z)); }
193 #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]);}
194 #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]);}
196 #define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
197 #define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
199 #define c_exp(R, Z) {pCf(R) = cexpf(Cf(Z));}
200 #define c_log(R, Z) {pCf(R) = clogf(Cf(Z));}
201 #define c_sin(R, Z) {pCf(R) = csinf(Cf(Z));}
202 //#define c_sqrt(R, Z) {*(R) = csqrtf(Cf(Z));}
203 #define c_sqrt(R, Z) {pCf(R) = csqrtf(Cf(Z));}
204 #define d_abs(x) (fabs(*(x)))
205 #define d_acos(x) (acos(*(x)))
206 #define d_asin(x) (asin(*(x)))
207 #define d_atan(x) (atan(*(x)))
208 #define d_atn2(x, y) (atan2(*(x),*(y)))
209 #define d_cnjg(R, Z) { pCd(R) = conj(Cd(Z)); }
210 #define r_cnjg(R, Z) { pCf(R) = conjf(Cf(Z)); }
211 #define d_cos(x) (cos(*(x)))
212 #define d_cosh(x) (cosh(*(x)))
213 #define d_dim(__a, __b) ( *(__a) > *(__b) ? *(__a) - *(__b) : 0.0 )
214 #define d_exp(x) (exp(*(x)))
215 #define d_imag(z) (cimag(Cd(z)))
216 #define r_imag(z) (cimagf(Cf(z)))
217 #define d_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
218 #define r_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
219 #define d_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
220 #define r_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
221 #define d_log(x) (log(*(x)))
222 #define d_mod(x, y) (fmod(*(x), *(y)))
223 #define u_nint(__x) ((__x)>=0 ? floor((__x) + .5) : -floor(.5 - (__x)))
224 #define d_nint(x) u_nint(*(x))
225 #define u_sign(__a,__b) ((__b) >= 0 ? ((__a) >= 0 ? (__a) : -(__a)) : -((__a) >= 0 ? (__a) : -(__a)))
226 #define d_sign(a,b) u_sign(*(a),*(b))
227 #define r_sign(a,b) u_sign(*(a),*(b))
228 #define d_sin(x) (sin(*(x)))
229 #define d_sinh(x) (sinh(*(x)))
230 #define d_sqrt(x) (sqrt(*(x)))
231 #define d_tan(x) (tan(*(x)))
232 #define d_tanh(x) (tanh(*(x)))
233 #define i_abs(x) abs(*(x))
234 #define i_dnnt(x) ((integer)u_nint(*(x)))
235 #define i_len(s, n) (n)
236 #define i_nint(x) ((integer)u_nint(*(x)))
237 #define i_sign(a,b) ((integer)u_sign((integer)*(a),(integer)*(b)))
238 #define pow_dd(ap, bp) ( pow(*(ap), *(bp)))
239 #define pow_si(B,E) spow_ui(*(B),*(E))
240 #define pow_ri(B,E) spow_ui(*(B),*(E))
241 #define pow_di(B,E) dpow_ui(*(B),*(E))
242 #define pow_zi(p, a, b) {pCd(p) = zpow_ui(Cd(a), *(b));}
243 #define pow_ci(p, a, b) {pCf(p) = cpow_ui(Cf(a), *(b));}
244 #define pow_zz(R,A,B) {pCd(R) = cpow(Cd(A),*(B));}
245 #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++ = ' '; }
246 #define s_cmp(a,b,c,d) ((integer)strncmp((a),(b),f2cmin((c),(d))))
247 #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]; }
248 #define sig_die(s, kill) { exit(1); }
249 #define s_stop(s, n) {exit(0);}
250 static char junk[] = "\n@(#)LIBF77 VERSION 19990503\n";
251 #define z_abs(z) (cabs(Cd(z)))
252 #define z_exp(R, Z) {pCd(R) = cexp(Cd(Z));}
253 #define z_sqrt(R, Z) {pCd(R) = csqrt(Cd(Z));}
254 #define myexit_() break;
255 #define mycycle() continue;
256 #define myceiling(w) {ceil(w)}
257 #define myhuge(w) {HUGE_VAL}
258 //#define mymaxloc_(w,s,e,n) {if (sizeof(*(w)) == sizeof(double)) dmaxloc_((w),*(s),*(e),n); else dmaxloc_((w),*(s),*(e),n);}
259 #define mymaxloc(w,s,e,n) {dmaxloc_(w,*(s),*(e),n)}
261 /* procedure parameter types for -A and -C++ */
263 #define F2C_proc_par_types 1
265 typedef logical (*L_fp)(...);
267 typedef logical (*L_fp)();
270 static float spow_ui(float x, integer n) {
271 float pow=1.0; unsigned long int u;
273 if(n < 0) n = -n, x = 1/x;
282 static double dpow_ui(double x, integer n) {
283 double pow=1.0; unsigned long int u;
285 if(n < 0) n = -n, x = 1/x;
295 static _Fcomplex cpow_ui(complex x, integer n) {
296 complex pow={1.0,0.0}; unsigned long int u;
298 if(n < 0) n = -n, x.r = 1/x.r, x.i=1/x.i;
300 if(u & 01) pow.r *= x.r, pow.i *= x.i;
301 if(u >>= 1) x.r *= x.r, x.i *= x.i;
305 _Fcomplex p={pow.r, pow.i};
309 static _Complex float cpow_ui(_Complex float x, integer n) {
310 _Complex float pow=1.0; unsigned long int u;
312 if(n < 0) n = -n, x = 1/x;
323 static _Dcomplex zpow_ui(_Dcomplex x, integer n) {
324 _Dcomplex pow={1.0,0.0}; unsigned long int u;
326 if(n < 0) n = -n, x._Val[0] = 1/x._Val[0], x._Val[1] =1/x._Val[1];
328 if(u & 01) pow._Val[0] *= x._Val[0], pow._Val[1] *= x._Val[1];
329 if(u >>= 1) x._Val[0] *= x._Val[0], x._Val[1] *= x._Val[1];
333 _Dcomplex p = {pow._Val[0], pow._Val[1]};
337 static _Complex double zpow_ui(_Complex double x, integer n) {
338 _Complex double pow=1.0; unsigned long int u;
340 if(n < 0) n = -n, x = 1/x;
350 static integer pow_ii(integer x, integer n) {
351 integer pow; unsigned long int u;
353 if (n == 0 || x == 1) pow = 1;
354 else if (x != -1) pow = x == 0 ? 1/x : 0;
357 if ((n > 0) || !(n == 0 || x == 1 || x != -1)) {
367 static integer dmaxloc_(double *w, integer s, integer e, integer *n)
369 double m; integer i, mi;
370 for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
371 if (w[i-1]>m) mi=i ,m=w[i-1];
374 static integer smaxloc_(float *w, integer s, integer e, integer *n)
376 float m; integer i, mi;
377 for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
378 if (w[i-1]>m) mi=i ,m=w[i-1];
381 static inline void cdotc_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
382 integer n = *n_, incx = *incx_, incy = *incy_, i;
384 _Fcomplex zdotc = {0.0, 0.0};
385 if (incx == 1 && incy == 1) {
386 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
387 zdotc._Val[0] += conjf(Cf(&x[i]))._Val[0] * Cf(&y[i])._Val[0];
388 zdotc._Val[1] += conjf(Cf(&x[i]))._Val[1] * Cf(&y[i])._Val[1];
391 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
392 zdotc._Val[0] += conjf(Cf(&x[i*incx]))._Val[0] * Cf(&y[i*incy])._Val[0];
393 zdotc._Val[1] += conjf(Cf(&x[i*incx]))._Val[1] * Cf(&y[i*incy])._Val[1];
399 _Complex float zdotc = 0.0;
400 if (incx == 1 && incy == 1) {
401 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
402 zdotc += conjf(Cf(&x[i])) * Cf(&y[i]);
405 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
406 zdotc += conjf(Cf(&x[i*incx])) * Cf(&y[i*incy]);
412 static inline void zdotc_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
413 integer n = *n_, incx = *incx_, incy = *incy_, i;
415 _Dcomplex zdotc = {0.0, 0.0};
416 if (incx == 1 && incy == 1) {
417 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
418 zdotc._Val[0] += conj(Cd(&x[i]))._Val[0] * Cd(&y[i])._Val[0];
419 zdotc._Val[1] += conj(Cd(&x[i]))._Val[1] * Cd(&y[i])._Val[1];
422 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
423 zdotc._Val[0] += conj(Cd(&x[i*incx]))._Val[0] * Cd(&y[i*incy])._Val[0];
424 zdotc._Val[1] += conj(Cd(&x[i*incx]))._Val[1] * Cd(&y[i*incy])._Val[1];
430 _Complex double zdotc = 0.0;
431 if (incx == 1 && incy == 1) {
432 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
433 zdotc += conj(Cd(&x[i])) * Cd(&y[i]);
436 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
437 zdotc += conj(Cd(&x[i*incx])) * Cd(&y[i*incy]);
443 static inline void cdotu_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
444 integer n = *n_, incx = *incx_, incy = *incy_, i;
446 _Fcomplex zdotc = {0.0, 0.0};
447 if (incx == 1 && incy == 1) {
448 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
449 zdotc._Val[0] += Cf(&x[i])._Val[0] * Cf(&y[i])._Val[0];
450 zdotc._Val[1] += Cf(&x[i])._Val[1] * Cf(&y[i])._Val[1];
453 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
454 zdotc._Val[0] += Cf(&x[i*incx])._Val[0] * Cf(&y[i*incy])._Val[0];
455 zdotc._Val[1] += Cf(&x[i*incx])._Val[1] * Cf(&y[i*incy])._Val[1];
461 _Complex float zdotc = 0.0;
462 if (incx == 1 && incy == 1) {
463 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
464 zdotc += Cf(&x[i]) * Cf(&y[i]);
467 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
468 zdotc += Cf(&x[i*incx]) * Cf(&y[i*incy]);
474 static inline void zdotu_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
475 integer n = *n_, incx = *incx_, incy = *incy_, i;
477 _Dcomplex zdotc = {0.0, 0.0};
478 if (incx == 1 && incy == 1) {
479 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
480 zdotc._Val[0] += Cd(&x[i])._Val[0] * Cd(&y[i])._Val[0];
481 zdotc._Val[1] += Cd(&x[i])._Val[1] * Cd(&y[i])._Val[1];
484 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
485 zdotc._Val[0] += Cd(&x[i*incx])._Val[0] * Cd(&y[i*incy])._Val[0];
486 zdotc._Val[1] += Cd(&x[i*incx])._Val[1] * Cd(&y[i*incy])._Val[1];
492 _Complex double zdotc = 0.0;
493 if (incx == 1 && incy == 1) {
494 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
495 zdotc += Cd(&x[i]) * Cd(&y[i]);
498 for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
499 zdotc += Cd(&x[i*incx]) * Cd(&y[i*incy]);
505 /* -- translated by f2c (version 20000121).
506 You must link the resulting object file with the libraries:
507 -lf2c -lm (in that order)
513 /* Table of constant values */
515 static real c_b9 = 0.f;
516 static real c_b10 = 1.f;
517 static integer c__0 = 0;
518 static integer c__1 = 1;
519 static integer c__2 = 2;
521 /* > \brief \b SSTEQR */
523 /* =========== DOCUMENTATION =========== */
525 /* Online html documentation available at */
526 /* http://www.netlib.org/lapack/explore-html/ */
529 /* > Download SSTEQR + dependencies */
530 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/ssteqr.
533 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/ssteqr.
536 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/ssteqr.
544 /* SUBROUTINE SSTEQR( COMPZ, N, D, E, Z, LDZ, WORK, INFO ) */
546 /* CHARACTER COMPZ */
547 /* INTEGER INFO, LDZ, N */
548 /* REAL D( * ), E( * ), WORK( * ), Z( LDZ, * ) */
551 /* > \par Purpose: */
556 /* > SSTEQR computes all eigenvalues and, optionally, eigenvectors of a */
557 /* > symmetric tridiagonal matrix using the implicit QL or QR method. */
558 /* > The eigenvectors of a full or band symmetric matrix can also be found */
559 /* > if SSYTRD or SSPTRD or SSBTRD has been used to reduce this matrix to */
560 /* > tridiagonal form. */
566 /* > \param[in] COMPZ */
568 /* > COMPZ is CHARACTER*1 */
569 /* > = 'N': Compute eigenvalues only. */
570 /* > = 'V': Compute eigenvalues and eigenvectors of the original */
571 /* > symmetric matrix. On entry, Z must contain the */
572 /* > orthogonal matrix used to reduce the original matrix */
573 /* > to tridiagonal form. */
574 /* > = 'I': Compute eigenvalues and eigenvectors of the */
575 /* > tridiagonal matrix. Z is initialized to the identity */
582 /* > The order of the matrix. N >= 0. */
585 /* > \param[in,out] D */
587 /* > D is REAL array, dimension (N) */
588 /* > On entry, the diagonal elements of the tridiagonal matrix. */
589 /* > On exit, if INFO = 0, the eigenvalues in ascending order. */
592 /* > \param[in,out] E */
594 /* > E is REAL array, dimension (N-1) */
595 /* > On entry, the (n-1) subdiagonal elements of the tridiagonal */
597 /* > On exit, E has been destroyed. */
600 /* > \param[in,out] Z */
602 /* > Z is REAL array, dimension (LDZ, N) */
603 /* > On entry, if COMPZ = 'V', then Z contains the orthogonal */
604 /* > matrix used in the reduction to tridiagonal form. */
605 /* > On exit, if INFO = 0, then if COMPZ = 'V', Z contains the */
606 /* > orthonormal eigenvectors of the original symmetric matrix, */
607 /* > and if COMPZ = 'I', Z contains the orthonormal eigenvectors */
608 /* > of the symmetric tridiagonal matrix. */
609 /* > If COMPZ = 'N', then Z is not referenced. */
612 /* > \param[in] LDZ */
614 /* > LDZ is INTEGER */
615 /* > The leading dimension of the array Z. LDZ >= 1, and if */
616 /* > eigenvectors are desired, then LDZ >= f2cmax(1,N). */
619 /* > \param[out] WORK */
621 /* > WORK is REAL array, dimension (f2cmax(1,2*N-2)) */
622 /* > If COMPZ = 'N', then WORK is not referenced. */
625 /* > \param[out] INFO */
627 /* > INFO is INTEGER */
628 /* > = 0: successful exit */
629 /* > < 0: if INFO = -i, the i-th argument had an illegal value */
630 /* > > 0: the algorithm has failed to find all the eigenvalues in */
631 /* > a total of 30*N iterations; if INFO = i, then i */
632 /* > elements of E have not converged to zero; on exit, D */
633 /* > and E contain the elements of a symmetric tridiagonal */
634 /* > matrix which is orthogonally similar to the original */
641 /* > \author Univ. of Tennessee */
642 /* > \author Univ. of California Berkeley */
643 /* > \author Univ. of Colorado Denver */
644 /* > \author NAG Ltd. */
646 /* > \date December 2016 */
648 /* > \ingroup auxOTHERcomputational */
650 /* ===================================================================== */
651 /* Subroutine */ int ssteqr_(char *compz, integer *n, real *d__, real *e,
652 real *z__, integer *ldz, real *work, integer *info)
654 /* System generated locals */
655 integer z_dim1, z_offset, i__1, i__2;
658 /* Local variables */
660 extern /* Subroutine */ int slae2_(real *, real *, real *, real *, real *)
663 integer i__, j, k, l, m;
665 extern logical lsame_(char *, char *);
667 extern /* Subroutine */ int slasr_(char *, char *, char *, integer *,
668 integer *, real *, real *, real *, integer *);
670 extern /* Subroutine */ int sswap_(integer *, real *, integer *, real *,
672 integer lendm1, lendp1;
673 extern /* Subroutine */ int slaev2_(real *, real *, real *, real *, real *
675 extern real slapy2_(real *, real *);
676 integer ii, mm, iscale;
677 extern real slamch_(char *);
679 extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
681 extern /* Subroutine */ int slascl_(char *, integer *, integer *, real *,
682 real *, integer *, integer *, real *, integer *, integer *);
684 extern /* Subroutine */ int slartg_(real *, real *, real *, real *, real *
685 ), slaset_(char *, integer *, integer *, real *, real *, real *,
688 integer nmaxit, icompz;
690 extern real slanst_(char *, integer *, real *, real *);
691 extern /* Subroutine */ int slasrt_(char *, integer *, real *, integer *);
692 integer lm1, mm1, nm1;
698 /* -- LAPACK computational routine (version 3.7.0) -- */
699 /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
700 /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
704 /* ===================================================================== */
707 /* Test the input parameters. */
709 /* Parameter adjustments */
713 z_offset = 1 + z_dim1 * 1;
720 if (lsame_(compz, "N")) {
722 } else if (lsame_(compz, "V")) {
724 } else if (lsame_(compz, "I")) {
733 } else if (*ldz < 1 || icompz > 0 && *ldz < f2cmax(1,*n)) {
738 xerbla_("SSTEQR", &i__1, (ftnlen)6);
742 /* Quick return if possible */
750 z__[z_dim1 + 1] = 1.f;
755 /* Determine the unit roundoff and over/underflow thresholds. */
758 /* Computing 2nd power */
761 safmin = slamch_("S");
762 safmax = 1.f / safmin;
763 ssfmax = sqrt(safmax) / 3.f;
764 ssfmin = sqrt(safmin) / eps2;
766 /* Compute the eigenvalues and eigenvectors of the tridiagonal */
770 slaset_("Full", n, n, &c_b9, &c_b10, &z__[z_offset], ldz);
776 /* Determine where the matrix splits and choose QL or QR iteration */
777 /* for each block, according to whether top or bottom diagonal */
778 /* element is smaller. */
792 for (m = l1; m <= i__1; ++m) {
793 tst = (r__1 = e[m], abs(r__1));
797 if (tst <= sqrt((r__1 = d__[m], abs(r__1))) * sqrt((r__2 = d__[m
798 + 1], abs(r__2))) * eps) {
817 /* Scale submatrix in rows and columns L to LEND */
820 anorm = slanst_("M", &i__1, &d__[l], &e[l]);
825 if (anorm > ssfmax) {
828 slascl_("G", &c__0, &c__0, &anorm, &ssfmax, &i__1, &c__1, &d__[l], n,
831 slascl_("G", &c__0, &c__0, &anorm, &ssfmax, &i__1, &c__1, &e[l], n,
833 } else if (anorm < ssfmin) {
836 slascl_("G", &c__0, &c__0, &anorm, &ssfmin, &i__1, &c__1, &d__[l], n,
839 slascl_("G", &c__0, &c__0, &anorm, &ssfmin, &i__1, &c__1, &e[l], n,
843 /* Choose between QL and QR iteration */
845 if ((r__1 = d__[lend], abs(r__1)) < (r__2 = d__[l], abs(r__2))) {
854 /* Look for small subdiagonal element. */
860 for (m = l; m <= i__1; ++m) {
861 /* Computing 2nd power */
862 r__2 = (r__1 = e[m], abs(r__1));
864 if (tst <= eps2 * (r__1 = d__[m], abs(r__1)) * (r__2 = d__[m
865 + 1], abs(r__2)) + safmin) {
883 /* If remaining matrix is 2-by-2, use SLAE2 or SLAEV2 */
884 /* to compute its eigensystem. */
888 slaev2_(&d__[l], &e[l], &d__[l + 1], &rt1, &rt2, &c__, &s);
890 work[*n - 1 + l] = s;
891 slasr_("R", "V", "B", n, &c__2, &work[l], &work[*n - 1 + l], &
892 z__[l * z_dim1 + 1], ldz);
894 slae2_(&d__[l], &e[l], &d__[l + 1], &rt1, &rt2);
906 if (jtot == nmaxit) {
913 g = (d__[l + 1] - p) / (e[l] * 2.f);
914 r__ = slapy2_(&g, &c_b10);
915 g = d__[m] - p + e[l] / (g + r_sign(&r__, &g));
925 for (i__ = mm1; i__ >= i__1; --i__) {
928 slartg_(&g, &f, &c__, &s, &r__);
932 g = d__[i__ + 1] - p;
933 r__ = (d__[i__] - g) * s + c__ * 2.f * b;
935 d__[i__ + 1] = g + p;
938 /* If eigenvectors are desired, then save rotations. */
942 work[*n - 1 + i__] = -s;
948 /* If eigenvectors are desired, then apply saved rotations. */
952 slasr_("R", "V", "B", n, &mm, &work[l], &work[*n - 1 + l], &z__[l
960 /* Eigenvalue found. */
975 /* Look for small superdiagonal element. */
981 for (m = l; m >= i__1; --m) {
982 /* Computing 2nd power */
983 r__2 = (r__1 = e[m - 1], abs(r__1));
985 if (tst <= eps2 * (r__1 = d__[m], abs(r__1)) * (r__2 = d__[m
986 - 1], abs(r__2)) + safmin) {
1004 /* If remaining matrix is 2-by-2, use SLAE2 or SLAEV2 */
1005 /* to compute its eigensystem. */
1009 slaev2_(&d__[l - 1], &e[l - 1], &d__[l], &rt1, &rt2, &c__, &s)
1012 work[*n - 1 + m] = s;
1013 slasr_("R", "V", "F", n, &c__2, &work[m], &work[*n - 1 + m], &
1014 z__[(l - 1) * z_dim1 + 1], ldz);
1016 slae2_(&d__[l - 1], &e[l - 1], &d__[l], &rt1, &rt2);
1028 if (jtot == nmaxit) {
1035 g = (d__[l - 1] - p) / (e[l - 1] * 2.f);
1036 r__ = slapy2_(&g, &c_b10);
1037 g = d__[m] - p + e[l - 1] / (g + r_sign(&r__, &g));
1047 for (i__ = m; i__ <= i__1; ++i__) {
1050 slartg_(&g, &f, &c__, &s, &r__);
1055 r__ = (d__[i__ + 1] - g) * s + c__ * 2.f * b;
1060 /* If eigenvectors are desired, then save rotations. */
1064 work[*n - 1 + i__] = s;
1070 /* If eigenvectors are desired, then apply saved rotations. */
1074 slasr_("R", "V", "F", n, &mm, &work[m], &work[*n - 1 + m], &z__[m
1075 * z_dim1 + 1], ldz);
1082 /* Eigenvalue found. */
1095 /* Undo scaling if necessary */
1099 i__1 = lendsv - lsv + 1;
1100 slascl_("G", &c__0, &c__0, &ssfmax, &anorm, &i__1, &c__1, &d__[lsv],
1102 i__1 = lendsv - lsv;
1103 slascl_("G", &c__0, &c__0, &ssfmax, &anorm, &i__1, &c__1, &e[lsv], n,
1105 } else if (iscale == 2) {
1106 i__1 = lendsv - lsv + 1;
1107 slascl_("G", &c__0, &c__0, &ssfmin, &anorm, &i__1, &c__1, &d__[lsv],
1109 i__1 = lendsv - lsv;
1110 slascl_("G", &c__0, &c__0, &ssfmin, &anorm, &i__1, &c__1, &e[lsv], n,
1114 /* Check for no convergence to an eigenvalue after a total */
1115 /* of N*MAXIT iterations. */
1117 if (jtot < nmaxit) {
1121 for (i__ = 1; i__ <= i__1; ++i__) {
1122 if (e[i__] != 0.f) {
1129 /* Order eigenvalues and eigenvectors. */
1134 /* Use Quick Sort */
1136 slasrt_("I", n, &d__[1], info);
1140 /* Use Selection Sort to minimize swaps of eigenvectors */
1143 for (ii = 2; ii <= i__1; ++ii) {
1148 for (j = ii; j <= i__2; ++j) {
1158 sswap_(n, &z__[i__ * z_dim1 + 1], &c__1, &z__[k * z_dim1 + 1],