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 integer c__9 = 9;
516 static integer c__0 = 0;
517 static integer c__2 = 2;
518 static doublereal c_b17 = 0.;
519 static doublereal c_b18 = 1.;
520 static integer c__1 = 1;
522 /* > \brief \b DSTEDC */
524 /* =========== DOCUMENTATION =========== */
526 /* Online html documentation available at */
527 /* http://www.netlib.org/lapack/explore-html/ */
530 /* > Download DSTEDC + dependencies */
531 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dstedc.
534 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dstedc.
537 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dstedc.
545 /* SUBROUTINE DSTEDC( COMPZ, N, D, E, Z, LDZ, WORK, LWORK, IWORK, */
548 /* CHARACTER COMPZ */
549 /* INTEGER INFO, LDZ, LIWORK, LWORK, N */
550 /* INTEGER IWORK( * ) */
551 /* DOUBLE PRECISION D( * ), E( * ), WORK( * ), Z( LDZ, * ) */
554 /* > \par Purpose: */
559 /* > DSTEDC computes all eigenvalues and, optionally, eigenvectors of a */
560 /* > symmetric tridiagonal matrix using the divide and conquer method. */
561 /* > The eigenvectors of a full or band real symmetric matrix can also be */
562 /* > found if DSYTRD or DSPTRD or DSBTRD has been used to reduce this */
563 /* > matrix to tridiagonal form. */
565 /* > This code makes very mild assumptions about floating point */
566 /* > arithmetic. It will work on machines with a guard digit in */
567 /* > add/subtract, or on those binary machines without guard digits */
568 /* > which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or Cray-2. */
569 /* > It could conceivably fail on hexadecimal or decimal machines */
570 /* > without guard digits, but we know of none. See DLAED3 for details. */
576 /* > \param[in] COMPZ */
578 /* > COMPZ is CHARACTER*1 */
579 /* > = 'N': Compute eigenvalues only. */
580 /* > = 'I': Compute eigenvectors of tridiagonal matrix also. */
581 /* > = 'V': Compute eigenvectors of original dense symmetric */
582 /* > matrix also. On entry, Z contains the orthogonal */
583 /* > matrix used to reduce the original matrix to */
584 /* > tridiagonal form. */
590 /* > The dimension of the symmetric tridiagonal matrix. N >= 0. */
593 /* > \param[in,out] D */
595 /* > D is DOUBLE PRECISION array, dimension (N) */
596 /* > On entry, the diagonal elements of the tridiagonal matrix. */
597 /* > On exit, if INFO = 0, the eigenvalues in ascending order. */
600 /* > \param[in,out] E */
602 /* > E is DOUBLE PRECISION array, dimension (N-1) */
603 /* > On entry, the subdiagonal elements of the tridiagonal matrix. */
604 /* > On exit, E has been destroyed. */
607 /* > \param[in,out] Z */
609 /* > Z is DOUBLE PRECISION array, dimension (LDZ,N) */
610 /* > On entry, if COMPZ = 'V', then Z contains the orthogonal */
611 /* > matrix used in the reduction to tridiagonal form. */
612 /* > On exit, if INFO = 0, then if COMPZ = 'V', Z contains the */
613 /* > orthonormal eigenvectors of the original symmetric matrix, */
614 /* > and if COMPZ = 'I', Z contains the orthonormal eigenvectors */
615 /* > of the symmetric tridiagonal matrix. */
616 /* > If COMPZ = 'N', then Z is not referenced. */
619 /* > \param[in] LDZ */
621 /* > LDZ is INTEGER */
622 /* > The leading dimension of the array Z. LDZ >= 1. */
623 /* > If eigenvectors are desired, then LDZ >= f2cmax(1,N). */
626 /* > \param[out] WORK */
628 /* > WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK)) */
629 /* > On exit, if INFO = 0, WORK(1) returns the optimal LWORK. */
632 /* > \param[in] LWORK */
634 /* > LWORK is INTEGER */
635 /* > The dimension of the array WORK. */
636 /* > If COMPZ = 'N' or N <= 1 then LWORK must be at least 1. */
637 /* > If COMPZ = 'V' and N > 1 then LWORK must be at least */
638 /* > ( 1 + 3*N + 2*N*lg N + 4*N**2 ), */
639 /* > where lg( N ) = smallest integer k such */
640 /* > that 2**k >= N. */
641 /* > If COMPZ = 'I' and N > 1 then LWORK must be at least */
642 /* > ( 1 + 4*N + N**2 ). */
643 /* > Note that for COMPZ = 'I' or 'V', then if N is less than or */
644 /* > equal to the minimum divide size, usually 25, then LWORK need */
645 /* > only be f2cmax(1,2*(N-1)). */
647 /* > If LWORK = -1, then a workspace query is assumed; the routine */
648 /* > only calculates the optimal size of the WORK array, returns */
649 /* > this value as the first entry of the WORK array, and no error */
650 /* > message related to LWORK is issued by XERBLA. */
653 /* > \param[out] IWORK */
655 /* > IWORK is INTEGER array, dimension (MAX(1,LIWORK)) */
656 /* > On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK. */
659 /* > \param[in] LIWORK */
661 /* > LIWORK is INTEGER */
662 /* > The dimension of the array IWORK. */
663 /* > If COMPZ = 'N' or N <= 1 then LIWORK must be at least 1. */
664 /* > If COMPZ = 'V' and N > 1 then LIWORK must be at least */
665 /* > ( 6 + 6*N + 5*N*lg N ). */
666 /* > If COMPZ = 'I' and N > 1 then LIWORK must be at least */
668 /* > Note that for COMPZ = 'I' or 'V', then if N is less than or */
669 /* > equal to the minimum divide size, usually 25, then LIWORK */
670 /* > need only be 1. */
672 /* > If LIWORK = -1, then a workspace query is assumed; the */
673 /* > routine only calculates the optimal size of the IWORK array, */
674 /* > returns this value as the first entry of the IWORK array, and */
675 /* > no error message related to LIWORK is issued by XERBLA. */
678 /* > \param[out] INFO */
680 /* > INFO is INTEGER */
681 /* > = 0: successful exit. */
682 /* > < 0: if INFO = -i, the i-th argument had an illegal value. */
683 /* > > 0: The algorithm failed to compute an eigenvalue while */
684 /* > working on the submatrix lying in rows and columns */
685 /* > INFO/(N+1) through mod(INFO,N+1). */
691 /* > \author Univ. of Tennessee */
692 /* > \author Univ. of California Berkeley */
693 /* > \author Univ. of Colorado Denver */
694 /* > \author NAG Ltd. */
696 /* > \date June 2017 */
698 /* > \ingroup auxOTHERcomputational */
700 /* > \par Contributors: */
701 /* ================== */
703 /* > Jeff Rutter, Computer Science Division, University of California */
704 /* > at Berkeley, USA \n */
705 /* > Modified by Francoise Tisseur, University of Tennessee */
707 /* ===================================================================== */
708 /* Subroutine */ int dstedc_(char *compz, integer *n, doublereal *d__,
709 doublereal *e, doublereal *z__, integer *ldz, doublereal *work,
710 integer *lwork, integer *iwork, integer *liwork, integer *info)
712 /* System generated locals */
713 integer z_dim1, z_offset, i__1, i__2;
714 doublereal d__1, d__2;
716 /* Local variables */
718 integer i__, j, k, m;
720 extern /* Subroutine */ int dgemm_(char *, char *, integer *, integer *,
721 integer *, doublereal *, doublereal *, integer *, doublereal *,
722 integer *, doublereal *, doublereal *, integer *);
723 extern logical lsame_(char *, char *);
724 extern /* Subroutine */ int dswap_(integer *, doublereal *, integer *,
725 doublereal *, integer *);
727 extern /* Subroutine */ int dlaed0_(integer *, integer *, integer *,
728 doublereal *, doublereal *, doublereal *, integer *, doublereal *,
729 integer *, doublereal *, integer *, integer *);
731 extern doublereal dlamch_(char *);
732 extern /* Subroutine */ int dlascl_(char *, integer *, integer *,
733 doublereal *, doublereal *, integer *, integer *, doublereal *,
734 integer *, integer *), dlacpy_(char *, integer *, integer
735 *, doublereal *, integer *, doublereal *, integer *),
736 dlaset_(char *, integer *, integer *, doublereal *, doublereal *,
737 doublereal *, integer *);
738 extern integer ilaenv_(integer *, char *, char *, integer *, integer *,
739 integer *, integer *, ftnlen, ftnlen);
740 extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
742 extern doublereal dlanst_(char *, integer *, doublereal *, doublereal *);
743 extern /* Subroutine */ int dsterf_(integer *, doublereal *, doublereal *,
744 integer *), dlasrt_(char *, integer *, doublereal *, integer *);
745 integer liwmin, icompz;
746 extern /* Subroutine */ int dsteqr_(char *, integer *, doublereal *,
747 doublereal *, doublereal *, integer *, doublereal *, integer *);
750 integer smlsiz, storez, strtrw, lgn;
754 /* -- LAPACK computational routine (version 3.7.1) -- */
755 /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
756 /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
760 /* ===================================================================== */
763 /* Test the input parameters. */
765 /* Parameter adjustments */
769 z_offset = 1 + z_dim1 * 1;
776 lquery = *lwork == -1 || *liwork == -1;
778 if (lsame_(compz, "N")) {
780 } else if (lsame_(compz, "V")) {
782 } else if (lsame_(compz, "I")) {
791 } else if (*ldz < 1 || icompz > 0 && *ldz < f2cmax(1,*n)) {
797 /* Compute the workspace requirements */
799 smlsiz = ilaenv_(&c__9, "DSTEDC", " ", &c__0, &c__0, &c__0, &c__0, (
800 ftnlen)6, (ftnlen)1);
801 if (*n <= 1 || icompz == 0) {
804 } else if (*n <= smlsiz) {
808 lgn = (integer) (log((doublereal) (*n)) / log(2.));
809 if (pow_ii(&c__2, &lgn) < *n) {
812 if (pow_ii(&c__2, &lgn) < *n) {
816 /* Computing 2nd power */
818 lwmin = *n * 3 + 1 + (*n << 1) * lgn + (i__1 * i__1 << 2);
819 liwmin = *n * 6 + 6 + *n * 5 * lgn;
820 } else if (icompz == 2) {
821 /* Computing 2nd power */
823 lwmin = (*n << 2) + 1 + i__1 * i__1;
827 work[1] = (doublereal) lwmin;
830 if (*lwork < lwmin && ! lquery) {
832 } else if (*liwork < liwmin && ! lquery) {
839 xerbla_("DSTEDC", &i__1, (ftnlen)6);
845 /* Quick return if possible */
852 z__[z_dim1 + 1] = 1.;
857 /* If the following conditional clause is removed, then the routine */
858 /* will use the Divide and Conquer routine to compute only the */
859 /* eigenvalues, which requires (3N + 3N**2) real workspace and */
860 /* (2 + 5N + 2N lg(N)) integer workspace. */
861 /* Since on many architectures DSTERF is much faster than any other */
862 /* algorithm for finding eigenvalues only, it is used here */
863 /* as the default. If the conditional clause is removed, then */
864 /* information on the size of workspace needs to be changed. */
866 /* If COMPZ = 'N', use DSTERF to compute the eigenvalues. */
869 dsterf_(n, &d__[1], &e[1], info);
873 /* If N is smaller than the minimum divide size (SMLSIZ+1), then */
874 /* solve the problem with another solver. */
878 dsteqr_(compz, n, &d__[1], &e[1], &z__[z_offset], ldz, &work[1], info);
882 /* If COMPZ = 'V', the Z matrix must be stored elsewhere for later */
886 storez = *n * *n + 1;
892 dlaset_("Full", n, n, &c_b17, &c_b18, &z__[z_offset], ldz);
897 orgnrm = dlanst_("M", n, &d__[1], &e[1]);
902 eps = dlamch_("Epsilon");
906 /* while ( START <= N ) */
911 /* Let FINISH be the position of the next subdiagonal entry */
912 /* such that E( FINISH ) <= TINY or FINISH = N if no such */
913 /* subdiagonal exists. The matrix identified by the elements */
914 /* between START and FINISH constitutes an independent */
920 tiny = eps * sqrt((d__1 = d__[finish], abs(d__1))) * sqrt((
921 d__2 = d__[finish + 1], abs(d__2)));
922 if ((d__1 = e[finish], abs(d__1)) > tiny) {
928 /* (Sub) Problem determined. Compute its size and solve it. */
930 m = finish - start + 1;
939 orgnrm = dlanst_("M", &m, &d__[start], &e[start]);
940 dlascl_("G", &c__0, &c__0, &orgnrm, &c_b18, &m, &c__1, &d__[
944 dlascl_("G", &c__0, &c__0, &orgnrm, &c_b18, &i__1, &c__1, &e[
945 start], &i__2, info);
952 dlaed0_(&icompz, n, &m, &d__[start], &e[start], &z__[strtrw +
953 start * z_dim1], ldz, &work[1], n, &work[storez], &
956 *info = (*info / (m + 1) + start - 1) * (*n + 1) + *info %
963 dlascl_("G", &c__0, &c__0, &c_b18, &orgnrm, &m, &c__1, &d__[
969 /* Since QR won't update a Z matrix which is larger than */
970 /* the length of D, we must solve the sub-problem in a */
971 /* workspace and then multiply back into Z. */
973 dsteqr_("I", &m, &d__[start], &e[start], &work[1], &m, &
974 work[m * m + 1], info);
975 dlacpy_("A", n, &m, &z__[start * z_dim1 + 1], ldz, &work[
977 dgemm_("N", "N", n, &m, &m, &c_b18, &work[storez], n, &
978 work[1], &m, &c_b17, &z__[start * z_dim1 + 1],
980 } else if (icompz == 2) {
981 dsteqr_("I", &m, &d__[start], &e[start], &z__[start +
982 start * z_dim1], ldz, &work[1], info);
984 dsterf_(&m, &d__[start], &e[start], info);
987 *info = start * (*n + 1) + finish;
1000 /* Use Quick Sort */
1002 dlasrt_("I", n, &d__[1], info);
1006 /* Use Selection Sort to minimize swaps of eigenvectors */
1009 for (ii = 2; ii <= i__1; ++ii) {
1014 for (j = ii; j <= i__2; ++j) {
1024 dswap_(n, &z__[i__ * z_dim1 + 1], &c__1, &z__[k * z_dim1
1033 work[1] = (doublereal) lwmin;