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__1 = 1;
516 static doublereal c_b25 = 1.;
517 static doublereal c_b27 = 0.;
519 /* > \brief \b DSBGVX */
521 /* =========== DOCUMENTATION =========== */
523 /* Online html documentation available at */
524 /* http://www.netlib.org/lapack/explore-html/ */
527 /* > Download DSBGVX + dependencies */
528 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dsbgvx.
531 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dsbgvx.
534 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dsbgvx.
542 /* SUBROUTINE DSBGVX( JOBZ, RANGE, UPLO, N, KA, KB, AB, LDAB, BB, */
543 /* LDBB, Q, LDQ, VL, VU, IL, IU, ABSTOL, M, W, Z, */
544 /* LDZ, WORK, IWORK, IFAIL, INFO ) */
546 /* CHARACTER JOBZ, RANGE, UPLO */
547 /* INTEGER IL, INFO, IU, KA, KB, LDAB, LDBB, LDQ, LDZ, M, */
549 /* DOUBLE PRECISION ABSTOL, VL, VU */
550 /* INTEGER IFAIL( * ), IWORK( * ) */
551 /* DOUBLE PRECISION AB( LDAB, * ), BB( LDBB, * ), Q( LDQ, * ), */
552 /* $ W( * ), WORK( * ), Z( LDZ, * ) */
555 /* > \par Purpose: */
560 /* > DSBGVX computes selected eigenvalues, and optionally, eigenvectors */
561 /* > of a real generalized symmetric-definite banded eigenproblem, of */
562 /* > the form A*x=(lambda)*B*x. Here A and B are assumed to be symmetric */
563 /* > and banded, and B is also positive definite. Eigenvalues and */
564 /* > eigenvectors can be selected by specifying either all eigenvalues, */
565 /* > a range of values or a range of indices for the desired eigenvalues. */
571 /* > \param[in] JOBZ */
573 /* > JOBZ is CHARACTER*1 */
574 /* > = 'N': Compute eigenvalues only; */
575 /* > = 'V': Compute eigenvalues and eigenvectors. */
578 /* > \param[in] RANGE */
580 /* > RANGE is CHARACTER*1 */
581 /* > = 'A': all eigenvalues will be found. */
582 /* > = 'V': all eigenvalues in the half-open interval (VL,VU] */
583 /* > will be found. */
584 /* > = 'I': the IL-th through IU-th eigenvalues will be found. */
587 /* > \param[in] UPLO */
589 /* > UPLO is CHARACTER*1 */
590 /* > = 'U': Upper triangles of A and B are stored; */
591 /* > = 'L': Lower triangles of A and B are stored. */
597 /* > The order of the matrices A and B. N >= 0. */
600 /* > \param[in] KA */
602 /* > KA is INTEGER */
603 /* > The number of superdiagonals of the matrix A if UPLO = 'U', */
604 /* > or the number of subdiagonals if UPLO = 'L'. KA >= 0. */
607 /* > \param[in] KB */
609 /* > KB is INTEGER */
610 /* > The number of superdiagonals of the matrix B if UPLO = 'U', */
611 /* > or the number of subdiagonals if UPLO = 'L'. KB >= 0. */
614 /* > \param[in,out] AB */
616 /* > AB is DOUBLE PRECISION array, dimension (LDAB, N) */
617 /* > On entry, the upper or lower triangle of the symmetric band */
618 /* > matrix A, stored in the first ka+1 rows of the array. The */
619 /* > j-th column of A is stored in the j-th column of the array AB */
621 /* > if UPLO = 'U', AB(ka+1+i-j,j) = A(i,j) for f2cmax(1,j-ka)<=i<=j; */
622 /* > if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=f2cmin(n,j+ka). */
624 /* > On exit, the contents of AB are destroyed. */
627 /* > \param[in] LDAB */
629 /* > LDAB is INTEGER */
630 /* > The leading dimension of the array AB. LDAB >= KA+1. */
633 /* > \param[in,out] BB */
635 /* > BB is DOUBLE PRECISION array, dimension (LDBB, N) */
636 /* > On entry, the upper or lower triangle of the symmetric band */
637 /* > matrix B, stored in the first kb+1 rows of the array. The */
638 /* > j-th column of B is stored in the j-th column of the array BB */
640 /* > if UPLO = 'U', BB(ka+1+i-j,j) = B(i,j) for f2cmax(1,j-kb)<=i<=j; */
641 /* > if UPLO = 'L', BB(1+i-j,j) = B(i,j) for j<=i<=f2cmin(n,j+kb). */
643 /* > On exit, the factor S from the split Cholesky factorization */
644 /* > B = S**T*S, as returned by DPBSTF. */
647 /* > \param[in] LDBB */
649 /* > LDBB is INTEGER */
650 /* > The leading dimension of the array BB. LDBB >= KB+1. */
653 /* > \param[out] Q */
655 /* > Q is DOUBLE PRECISION array, dimension (LDQ, N) */
656 /* > If JOBZ = 'V', the n-by-n matrix used in the reduction of */
657 /* > A*x = (lambda)*B*x to standard form, i.e. C*x = (lambda)*x, */
658 /* > and consequently C to tridiagonal form. */
659 /* > If JOBZ = 'N', the array Q is not referenced. */
662 /* > \param[in] LDQ */
664 /* > LDQ is INTEGER */
665 /* > The leading dimension of the array Q. If JOBZ = 'N', */
666 /* > LDQ >= 1. If JOBZ = 'V', LDQ >= f2cmax(1,N). */
669 /* > \param[in] VL */
671 /* > VL is DOUBLE PRECISION */
673 /* > If RANGE='V', the lower bound of the interval to */
674 /* > be searched for eigenvalues. VL < VU. */
675 /* > Not referenced if RANGE = 'A' or 'I'. */
678 /* > \param[in] VU */
680 /* > VU is DOUBLE PRECISION */
682 /* > If RANGE='V', the upper bound of the interval to */
683 /* > be searched for eigenvalues. VL < VU. */
684 /* > Not referenced if RANGE = 'A' or 'I'. */
687 /* > \param[in] IL */
689 /* > IL is INTEGER */
691 /* > If RANGE='I', the index of the */
692 /* > smallest eigenvalue to be returned. */
693 /* > 1 <= IL <= IU <= N, if N > 0; IL = 1 and IU = 0 if N = 0. */
694 /* > Not referenced if RANGE = 'A' or 'V'. */
697 /* > \param[in] IU */
699 /* > IU is INTEGER */
701 /* > If RANGE='I', the index of the */
702 /* > largest eigenvalue to be returned. */
703 /* > 1 <= IL <= IU <= N, if N > 0; IL = 1 and IU = 0 if N = 0. */
704 /* > Not referenced if RANGE = 'A' or 'V'. */
707 /* > \param[in] ABSTOL */
709 /* > ABSTOL is DOUBLE PRECISION */
710 /* > The absolute error tolerance for the eigenvalues. */
711 /* > An approximate eigenvalue is accepted as converged */
712 /* > when it is determined to lie in an interval [a,b] */
713 /* > of width less than or equal to */
715 /* > ABSTOL + EPS * f2cmax( |a|,|b| ) , */
717 /* > where EPS is the machine precision. If ABSTOL is less than */
718 /* > or equal to zero, then EPS*|T| will be used in its place, */
719 /* > where |T| is the 1-norm of the tridiagonal matrix obtained */
720 /* > by reducing A to tridiagonal form. */
722 /* > Eigenvalues will be computed most accurately when ABSTOL is */
723 /* > set to twice the underflow threshold 2*DLAMCH('S'), not zero. */
724 /* > If this routine returns with INFO>0, indicating that some */
725 /* > eigenvectors did not converge, try setting ABSTOL to */
726 /* > 2*DLAMCH('S'). */
729 /* > \param[out] M */
732 /* > The total number of eigenvalues found. 0 <= M <= N. */
733 /* > If RANGE = 'A', M = N, and if RANGE = 'I', M = IU-IL+1. */
736 /* > \param[out] W */
738 /* > W is DOUBLE PRECISION array, dimension (N) */
739 /* > If INFO = 0, the eigenvalues in ascending order. */
742 /* > \param[out] Z */
744 /* > Z is DOUBLE PRECISION array, dimension (LDZ, N) */
745 /* > If JOBZ = 'V', then if INFO = 0, Z contains the matrix Z of */
746 /* > eigenvectors, with the i-th column of Z holding the */
747 /* > eigenvector associated with W(i). The eigenvectors are */
748 /* > normalized so Z**T*B*Z = I. */
749 /* > If JOBZ = 'N', then Z is not referenced. */
752 /* > \param[in] LDZ */
754 /* > LDZ is INTEGER */
755 /* > The leading dimension of the array Z. LDZ >= 1, and if */
756 /* > JOBZ = 'V', LDZ >= f2cmax(1,N). */
759 /* > \param[out] WORK */
761 /* > WORK is DOUBLE PRECISION array, dimension (7*N) */
764 /* > \param[out] IWORK */
766 /* > IWORK is INTEGER array, dimension (5*N) */
769 /* > \param[out] IFAIL */
771 /* > IFAIL is INTEGER array, dimension (M) */
772 /* > If JOBZ = 'V', then if INFO = 0, the first M elements of */
773 /* > IFAIL are zero. If INFO > 0, then IFAIL contains the */
774 /* > indices of the eigenvalues that failed to converge. */
775 /* > If JOBZ = 'N', then IFAIL is not referenced. */
778 /* > \param[out] INFO */
780 /* > INFO is INTEGER */
781 /* > = 0: successful exit */
782 /* > < 0: if INFO = -i, the i-th argument had an illegal value */
783 /* > <= N: if INFO = i, then i eigenvectors failed to converge. */
784 /* > Their indices are stored in IFAIL. */
785 /* > > N: DPBSTF returned an error code; i.e., */
786 /* > if INFO = N + i, for 1 <= i <= N, then the leading */
787 /* > minor of order i of B is not positive definite. */
788 /* > The factorization of B could not be completed and */
789 /* > no eigenvalues or eigenvectors were computed. */
795 /* > \author Univ. of Tennessee */
796 /* > \author Univ. of California Berkeley */
797 /* > \author Univ. of Colorado Denver */
798 /* > \author NAG Ltd. */
800 /* > \date June 2016 */
802 /* > \ingroup doubleOTHEReigen */
804 /* > \par Contributors: */
805 /* ================== */
807 /* > Mark Fahey, Department of Mathematics, Univ. of Kentucky, USA */
809 /* ===================================================================== */
810 /* Subroutine */ int dsbgvx_(char *jobz, char *range, char *uplo, integer *n,
811 integer *ka, integer *kb, doublereal *ab, integer *ldab, doublereal *
812 bb, integer *ldbb, doublereal *q, integer *ldq, doublereal *vl,
813 doublereal *vu, integer *il, integer *iu, doublereal *abstol, integer
814 *m, doublereal *w, doublereal *z__, integer *ldz, doublereal *work,
815 integer *iwork, integer *ifail, integer *info)
817 /* System generated locals */
818 integer ab_dim1, ab_offset, bb_dim1, bb_offset, q_dim1, q_offset, z_dim1,
819 z_offset, i__1, i__2;
821 /* Local variables */
825 integer itmp1, i__, j, indee;
826 extern logical lsame_(char *, char *);
827 extern /* Subroutine */ int dgemv_(char *, integer *, integer *,
828 doublereal *, doublereal *, integer *, doublereal *, integer *,
829 doublereal *, doublereal *, integer *);
832 extern /* Subroutine */ int dcopy_(integer *, doublereal *, integer *,
833 doublereal *, integer *), dswap_(integer *, doublereal *, integer
834 *, doublereal *, integer *);
835 logical upper, wantz;
837 logical alleig, indeig;
840 extern /* Subroutine */ int dlacpy_(char *, integer *, integer *,
841 doublereal *, integer *, doublereal *, integer *),
842 xerbla_(char *, integer *, ftnlen), dpbstf_(char *, integer *,
843 integer *, doublereal *, integer *, integer *), dsbtrd_(
844 char *, char *, integer *, integer *, doublereal *, integer *,
845 doublereal *, doublereal *, doublereal *, integer *, doublereal *,
848 extern /* Subroutine */ int dsbgst_(char *, char *, integer *, integer *,
849 integer *, doublereal *, integer *, doublereal *, integer *,
850 doublereal *, integer *, doublereal *, integer *),
851 dstein_(integer *, doublereal *, doublereal *, integer *,
852 doublereal *, integer *, integer *, doublereal *, integer *,
853 doublereal *, integer *, integer *, integer *);
855 extern /* Subroutine */ int dsterf_(integer *, doublereal *, doublereal *,
856 integer *), dstebz_(char *, char *, integer *, doublereal *,
857 doublereal *, integer *, integer *, doublereal *, doublereal *,
858 doublereal *, integer *, integer *, doublereal *, integer *,
859 integer *, doublereal *, integer *, integer *);
861 extern /* Subroutine */ int dsteqr_(char *, integer *, doublereal *,
862 doublereal *, doublereal *, integer *, doublereal *, integer *);
867 /* -- LAPACK driver routine (version 3.7.0) -- */
868 /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
869 /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
873 /* ===================================================================== */
876 /* Test the input parameters. */
878 /* Parameter adjustments */
880 ab_offset = 1 + ab_dim1 * 1;
883 bb_offset = 1 + bb_dim1 * 1;
886 q_offset = 1 + q_dim1 * 1;
890 z_offset = 1 + z_dim1 * 1;
897 wantz = lsame_(jobz, "V");
898 upper = lsame_(uplo, "U");
899 alleig = lsame_(range, "A");
900 valeig = lsame_(range, "V");
901 indeig = lsame_(range, "I");
904 if (! (wantz || lsame_(jobz, "N"))) {
906 } else if (! (alleig || valeig || indeig)) {
908 } else if (! (upper || lsame_(uplo, "L"))) {
912 } else if (*ka < 0) {
914 } else if (*kb < 0 || *kb > *ka) {
916 } else if (*ldab < *ka + 1) {
918 } else if (*ldbb < *kb + 1) {
920 } else if (*ldq < 1 || wantz && *ldq < *n) {
924 if (*n > 0 && *vu <= *vl) {
928 if (*il < 1 || *il > f2cmax(1,*n)) {
930 } else if (*iu < f2cmin(*n,*il) || *iu > *n) {
936 if (*ldz < 1 || wantz && *ldz < *n) {
943 xerbla_("DSBGVX", &i__1, (ftnlen)6);
947 /* Quick return if possible */
954 /* Form a split Cholesky factorization of B. */
956 dpbstf_(uplo, n, kb, &bb[bb_offset], ldbb, info);
962 /* Transform problem to standard eigenvalue problem. */
964 dsbgst_(jobz, uplo, n, ka, kb, &ab[ab_offset], ldab, &bb[bb_offset], ldbb,
965 &q[q_offset], ldq, &work[1], &iinfo);
967 /* Reduce symmetric band matrix to tridiagonal form. */
973 *(unsigned char *)vect = 'U';
975 *(unsigned char *)vect = 'N';
977 dsbtrd_(vect, uplo, n, ka, &ab[ab_offset], ldab, &work[indd], &work[inde],
978 &q[q_offset], ldq, &work[indwrk], &iinfo);
980 /* If all eigenvalues are desired and ABSTOL is less than or equal */
981 /* to zero, then call DSTERF or SSTEQR. If this fails for some */
982 /* eigenvalue, then try DSTEBZ. */
986 if (*il == 1 && *iu == *n) {
990 if ((alleig || test) && *abstol <= 0.) {
991 dcopy_(n, &work[indd], &c__1, &w[1], &c__1);
992 indee = indwrk + (*n << 1);
994 dcopy_(&i__1, &work[inde], &c__1, &work[indee], &c__1);
996 dsterf_(n, &w[1], &work[indee], info);
998 dlacpy_("A", n, n, &q[q_offset], ldq, &z__[z_offset], ldz);
999 dsteqr_(jobz, n, &w[1], &work[indee], &z__[z_offset], ldz, &work[
1003 for (i__ = 1; i__ <= i__1; ++i__) {
1016 /* Otherwise, call DSTEBZ and, if eigenvectors are desired, */
1020 *(unsigned char *)order = 'B';
1022 *(unsigned char *)order = 'E';
1025 indisp = indibl + *n;
1026 indiwo = indisp + *n;
1027 dstebz_(range, order, n, vl, vu, il, iu, abstol, &work[indd], &work[inde],
1028 m, &nsplit, &w[1], &iwork[indibl], &iwork[indisp], &work[indwrk],
1029 &iwork[indiwo], info);
1032 dstein_(n, &work[indd], &work[inde], m, &w[1], &iwork[indibl], &iwork[
1033 indisp], &z__[z_offset], ldz, &work[indwrk], &iwork[indiwo], &
1036 /* Apply transformation matrix used in reduction to tridiagonal */
1037 /* form to eigenvectors returned by DSTEIN. */
1040 for (j = 1; j <= i__1; ++j) {
1041 dcopy_(n, &z__[j * z_dim1 + 1], &c__1, &work[1], &c__1);
1042 dgemv_("N", n, n, &c_b25, &q[q_offset], ldq, &work[1], &c__1, &
1043 c_b27, &z__[j * z_dim1 + 1], &c__1);
1050 /* If eigenvalues are not in order, then sort them, along with */
1055 for (j = 1; j <= i__1; ++j) {
1059 for (jj = j + 1; jj <= i__2; ++jj) {
1068 itmp1 = iwork[indibl + i__ - 1];
1070 iwork[indibl + i__ - 1] = iwork[indibl + j - 1];
1072 iwork[indibl + j - 1] = itmp1;
1073 dswap_(n, &z__[i__ * z_dim1 + 1], &c__1, &z__[j * z_dim1 + 1],
1077 ifail[i__] = ifail[j];