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]/Cd(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 /* > \brief \b ZLAR1V computes the (scaled) r-th column of the inverse of the submatrix in rows b1 through bn
514 of the tridiagonal matrix LDLT - λI. */
516 /* =========== DOCUMENTATION =========== */
518 /* Online html documentation available at */
519 /* http://www.netlib.org/lapack/explore-html/ */
522 /* > Download ZLAR1V + dependencies */
523 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlar1v.
526 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlar1v.
529 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlar1v.
537 /* SUBROUTINE ZLAR1V( N, B1, BN, LAMBDA, D, L, LD, LLD, */
538 /* PIVMIN, GAPTOL, Z, WANTNC, NEGCNT, ZTZ, MINGMA, */
539 /* R, ISUPPZ, NRMINV, RESID, RQCORR, WORK ) */
542 /* INTEGER B1, BN, N, NEGCNT, R */
543 /* DOUBLE PRECISION GAPTOL, LAMBDA, MINGMA, NRMINV, PIVMIN, RESID, */
545 /* INTEGER ISUPPZ( * ) */
546 /* DOUBLE PRECISION D( * ), L( * ), LD( * ), LLD( * ), */
548 /* COMPLEX*16 Z( * ) */
551 /* > \par Purpose: */
556 /* > ZLAR1V computes the (scaled) r-th column of the inverse of */
557 /* > the sumbmatrix in rows B1 through BN of the tridiagonal matrix */
558 /* > L D L**T - sigma I. When sigma is close to an eigenvalue, the */
559 /* > computed vector is an accurate eigenvector. Usually, r corresponds */
560 /* > to the index where the eigenvector is largest in magnitude. */
561 /* > The following steps accomplish this computation : */
562 /* > (a) Stationary qd transform, L D L**T - sigma I = L(+) D(+) L(+)**T, */
563 /* > (b) Progressive qd transform, L D L**T - sigma I = U(-) D(-) U(-)**T, */
564 /* > (c) Computation of the diagonal elements of the inverse of */
565 /* > L D L**T - sigma I by combining the above transforms, and choosing */
566 /* > r as the index where the diagonal of the inverse is (one of the) */
567 /* > largest in magnitude. */
568 /* > (d) Computation of the (scaled) r-th column of the inverse using the */
569 /* > twisted factorization obtained by combining the top part of the */
570 /* > the stationary and the bottom part of the progressive transform. */
579 /* > The order of the matrix L D L**T. */
582 /* > \param[in] B1 */
584 /* > B1 is INTEGER */
585 /* > First index of the submatrix of L D L**T. */
588 /* > \param[in] BN */
590 /* > BN is INTEGER */
591 /* > Last index of the submatrix of L D L**T. */
594 /* > \param[in] LAMBDA */
596 /* > LAMBDA is DOUBLE PRECISION */
597 /* > The shift. In order to compute an accurate eigenvector, */
598 /* > LAMBDA should be a good approximation to an eigenvalue */
604 /* > L is DOUBLE PRECISION array, dimension (N-1) */
605 /* > The (n-1) subdiagonal elements of the unit bidiagonal matrix */
606 /* > L, in elements 1 to N-1. */
611 /* > D is DOUBLE PRECISION array, dimension (N) */
612 /* > The n diagonal elements of the diagonal matrix D. */
615 /* > \param[in] LD */
617 /* > LD is DOUBLE PRECISION array, dimension (N-1) */
618 /* > The n-1 elements L(i)*D(i). */
621 /* > \param[in] LLD */
623 /* > LLD is DOUBLE PRECISION array, dimension (N-1) */
624 /* > The n-1 elements L(i)*L(i)*D(i). */
627 /* > \param[in] PIVMIN */
629 /* > PIVMIN is DOUBLE PRECISION */
630 /* > The minimum pivot in the Sturm sequence. */
633 /* > \param[in] GAPTOL */
635 /* > GAPTOL is DOUBLE PRECISION */
636 /* > Tolerance that indicates when eigenvector entries are negligible */
637 /* > w.r.t. their contribution to the residual. */
640 /* > \param[in,out] Z */
642 /* > Z is COMPLEX*16 array, dimension (N) */
643 /* > On input, all entries of Z must be set to 0. */
644 /* > On output, Z contains the (scaled) r-th column of the */
645 /* > inverse. The scaling is such that Z(R) equals 1. */
648 /* > \param[in] WANTNC */
650 /* > WANTNC is LOGICAL */
651 /* > Specifies whether NEGCNT has to be computed. */
654 /* > \param[out] NEGCNT */
656 /* > NEGCNT is INTEGER */
657 /* > If WANTNC is .TRUE. then NEGCNT = the number of pivots < pivmin */
658 /* > in the matrix factorization L D L**T, and NEGCNT = -1 otherwise. */
661 /* > \param[out] ZTZ */
663 /* > ZTZ is DOUBLE PRECISION */
664 /* > The square of the 2-norm of Z. */
667 /* > \param[out] MINGMA */
669 /* > MINGMA is DOUBLE PRECISION */
670 /* > The reciprocal of the largest (in magnitude) diagonal */
671 /* > element of the inverse of L D L**T - sigma I. */
674 /* > \param[in,out] R */
677 /* > The twist index for the twisted factorization used to */
679 /* > On input, 0 <= R <= N. If R is input as 0, R is set to */
680 /* > the index where (L D L**T - sigma I)^{-1} is largest */
681 /* > in magnitude. If 1 <= R <= N, R is unchanged. */
682 /* > On output, R contains the twist index used to compute Z. */
683 /* > Ideally, R designates the position of the maximum entry in the */
687 /* > \param[out] ISUPPZ */
689 /* > ISUPPZ is INTEGER array, dimension (2) */
690 /* > The support of the vector in Z, i.e., the vector Z is */
691 /* > nonzero only in elements ISUPPZ(1) through ISUPPZ( 2 ). */
694 /* > \param[out] NRMINV */
696 /* > NRMINV is DOUBLE PRECISION */
697 /* > NRMINV = 1/SQRT( ZTZ ) */
700 /* > \param[out] RESID */
702 /* > RESID is DOUBLE PRECISION */
703 /* > The residual of the FP vector. */
704 /* > RESID = ABS( MINGMA )/SQRT( ZTZ ) */
707 /* > \param[out] RQCORR */
709 /* > RQCORR is DOUBLE PRECISION */
710 /* > The Rayleigh Quotient correction to LAMBDA. */
711 /* > RQCORR = MINGMA*TMP */
714 /* > \param[out] WORK */
716 /* > WORK is DOUBLE PRECISION array, dimension (4*N) */
722 /* > \author Univ. of Tennessee */
723 /* > \author Univ. of California Berkeley */
724 /* > \author Univ. of Colorado Denver */
725 /* > \author NAG Ltd. */
727 /* > \date December 2016 */
729 /* > \ingroup complex16OTHERauxiliary */
731 /* > \par Contributors: */
732 /* ================== */
734 /* > Beresford Parlett, University of California, Berkeley, USA \n */
735 /* > Jim Demmel, University of California, Berkeley, USA \n */
736 /* > Inderjit Dhillon, University of Texas, Austin, USA \n */
737 /* > Osni Marques, LBNL/NERSC, USA \n */
738 /* > Christof Voemel, University of California, Berkeley, USA */
740 /* ===================================================================== */
741 /* Subroutine */ int zlar1v_(integer *n, integer *b1, integer *bn, doublereal
742 *lambda, doublereal *d__, doublereal *l, doublereal *ld, doublereal *
743 lld, doublereal *pivmin, doublereal *gaptol, doublecomplex *z__,
744 logical *wantnc, integer *negcnt, doublereal *ztz, doublereal *mingma,
745 integer *r__, integer *isuppz, doublereal *nrminv, doublereal *resid,
746 doublereal *rqcorr, doublereal *work)
748 /* System generated locals */
749 integer i__1, i__2, i__3, i__4;
751 doublecomplex z__1, z__2;
753 /* Local variables */
754 integer indp, inds, i__;
757 extern doublereal dlamch_(char *);
758 extern logical disnan_(doublereal *);
759 integer indlpl, indumn;
761 logical sawnan1, sawnan2;
766 /* -- LAPACK auxiliary routine (version 3.7.0) -- */
767 /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
768 /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
772 /* ===================================================================== */
775 /* Parameter adjustments */
785 eps = dlamch_("Precision");
793 /* Storage for LPLUS */
795 /* Storage for UMINUS */
797 inds = (*n << 1) + 1;
802 work[inds + *b1 - 1] = lld[*b1 - 1];
805 /* Compute the stationary transform (using the differential form) */
806 /* until the index R2. */
810 s = work[inds + *b1 - 1] - *lambda;
812 for (i__ = *b1; i__ <= i__1; ++i__) {
813 dplus = d__[i__] + s;
814 work[indlpl + i__] = ld[i__] / dplus;
818 work[inds + i__] = s * work[indlpl + i__] * l[i__];
819 s = work[inds + i__] - *lambda;
822 sawnan1 = disnan_(&s);
827 for (i__ = r1; i__ <= i__1; ++i__) {
828 dplus = d__[i__] + s;
829 work[indlpl + i__] = ld[i__] / dplus;
830 work[inds + i__] = s * work[indlpl + i__] * l[i__];
831 s = work[inds + i__] - *lambda;
834 sawnan1 = disnan_(&s);
838 /* Runs a slower version of the above loop if a NaN is detected */
840 s = work[inds + *b1 - 1] - *lambda;
842 for (i__ = *b1; i__ <= i__1; ++i__) {
843 dplus = d__[i__] + s;
844 if (abs(dplus) < *pivmin) {
847 work[indlpl + i__] = ld[i__] / dplus;
851 work[inds + i__] = s * work[indlpl + i__] * l[i__];
852 if (work[indlpl + i__] == 0.) {
853 work[inds + i__] = lld[i__];
855 s = work[inds + i__] - *lambda;
859 for (i__ = r1; i__ <= i__1; ++i__) {
860 dplus = d__[i__] + s;
861 if (abs(dplus) < *pivmin) {
864 work[indlpl + i__] = ld[i__] / dplus;
865 work[inds + i__] = s * work[indlpl + i__] * l[i__];
866 if (work[indlpl + i__] == 0.) {
867 work[inds + i__] = lld[i__];
869 s = work[inds + i__] - *lambda;
874 /* Compute the progressive transform (using the differential form) */
875 /* until the index R1 */
879 work[indp + *bn - 1] = d__[*bn] - *lambda;
881 for (i__ = *bn - 1; i__ >= i__1; --i__) {
882 dminus = lld[i__] + work[indp + i__];
883 tmp = d__[i__] / dminus;
887 work[indumn + i__] = l[i__] * tmp;
888 work[indp + i__ - 1] = work[indp + i__] * tmp - *lambda;
891 tmp = work[indp + r1 - 1];
892 sawnan2 = disnan_(&tmp);
894 /* Runs a slower version of the above loop if a NaN is detected */
897 for (i__ = *bn - 1; i__ >= i__1; --i__) {
898 dminus = lld[i__] + work[indp + i__];
899 if (abs(dminus) < *pivmin) {
902 tmp = d__[i__] / dminus;
906 work[indumn + i__] = l[i__] * tmp;
907 work[indp + i__ - 1] = work[indp + i__] * tmp - *lambda;
909 work[indp + i__ - 1] = d__[i__] - *lambda;
915 /* Find the index (from R1 to R2) of the largest (in magnitude) */
916 /* diagonal element of the inverse */
918 *mingma = work[inds + r1 - 1] + work[indp + r1 - 1];
923 *negcnt = neg1 + neg2;
927 if (abs(*mingma) == 0.) {
928 *mingma = eps * work[inds + r1 - 1];
932 for (i__ = r1; i__ <= i__1; ++i__) {
933 tmp = work[inds + i__] + work[indp + i__];
935 tmp = eps * work[inds + i__];
937 if (abs(tmp) <= abs(*mingma)) {
944 /* Compute the FP vector: solve N^T v = e_r */
949 z__[i__1].r = 1., z__[i__1].i = 0.;
952 /* Compute the FP vector upwards from R */
954 if (! sawnan1 && ! sawnan2) {
956 for (i__ = *r__ - 1; i__ >= i__1; --i__) {
960 z__2.r = work[i__3] * z__[i__4].r, z__2.i = work[i__3] * z__[i__4]
962 z__1.r = -z__2.r, z__1.i = -z__2.i;
963 z__[i__2].r = z__1.r, z__[i__2].i = z__1.i;
964 if ((z_abs(&z__[i__]) + z_abs(&z__[i__ + 1])) * (d__1 = ld[i__],
965 abs(d__1)) < *gaptol) {
967 z__[i__2].r = 0., z__[i__2].i = 0.;
973 z__1.r = z__[i__2].r * z__[i__3].r - z__[i__2].i * z__[i__3].i,
974 z__1.i = z__[i__2].r * z__[i__3].i + z__[i__2].i * z__[
982 /* Run slower loop if NaN occurred. */
984 for (i__ = *r__ - 1; i__ >= i__1; --i__) {
986 if (z__[i__2].r == 0. && z__[i__2].i == 0.) {
988 d__1 = -(ld[i__ + 1] / ld[i__]);
990 z__1.r = d__1 * z__[i__3].r, z__1.i = d__1 * z__[i__3].i;
991 z__[i__2].r = z__1.r, z__[i__2].i = z__1.i;
996 z__2.r = work[i__3] * z__[i__4].r, z__2.i = work[i__3] * z__[
998 z__1.r = -z__2.r, z__1.i = -z__2.i;
999 z__[i__2].r = z__1.r, z__[i__2].i = z__1.i;
1001 if ((z_abs(&z__[i__]) + z_abs(&z__[i__ + 1])) * (d__1 = ld[i__],
1002 abs(d__1)) < *gaptol) {
1004 z__[i__2].r = 0., z__[i__2].i = 0.;
1005 isuppz[1] = i__ + 1;
1010 z__1.r = z__[i__2].r * z__[i__3].r - z__[i__2].i * z__[i__3].i,
1011 z__1.i = z__[i__2].r * z__[i__3].i + z__[i__2].i * z__[
1019 /* Compute the FP vector downwards from R in blocks of size BLKSIZ */
1020 if (! sawnan1 && ! sawnan2) {
1022 for (i__ = *r__; i__ <= i__1; ++i__) {
1024 i__3 = indumn + i__;
1026 z__2.r = work[i__3] * z__[i__4].r, z__2.i = work[i__3] * z__[i__4]
1028 z__1.r = -z__2.r, z__1.i = -z__2.i;
1029 z__[i__2].r = z__1.r, z__[i__2].i = z__1.i;
1030 if ((z_abs(&z__[i__]) + z_abs(&z__[i__ + 1])) * (d__1 = ld[i__],
1031 abs(d__1)) < *gaptol) {
1033 z__[i__2].r = 0., z__[i__2].i = 0.;
1039 z__1.r = z__[i__2].r * z__[i__3].r - z__[i__2].i * z__[i__3].i,
1040 z__1.i = z__[i__2].r * z__[i__3].i + z__[i__2].i * z__[
1048 /* Run slower loop if NaN occurred. */
1050 for (i__ = *r__; i__ <= i__1; ++i__) {
1052 if (z__[i__2].r == 0. && z__[i__2].i == 0.) {
1054 d__1 = -(ld[i__ - 1] / ld[i__]);
1056 z__1.r = d__1 * z__[i__3].r, z__1.i = d__1 * z__[i__3].i;
1057 z__[i__2].r = z__1.r, z__[i__2].i = z__1.i;
1060 i__3 = indumn + i__;
1062 z__2.r = work[i__3] * z__[i__4].r, z__2.i = work[i__3] * z__[
1064 z__1.r = -z__2.r, z__1.i = -z__2.i;
1065 z__[i__2].r = z__1.r, z__[i__2].i = z__1.i;
1067 if ((z_abs(&z__[i__]) + z_abs(&z__[i__ + 1])) * (d__1 = ld[i__],
1068 abs(d__1)) < *gaptol) {
1070 z__[i__2].r = 0., z__[i__2].i = 0.;
1076 z__1.r = z__[i__2].r * z__[i__3].r - z__[i__2].i * z__[i__3].i,
1077 z__1.i = z__[i__2].r * z__[i__3].i + z__[i__2].i * z__[
1086 /* Compute quantities for convergence test */
1089 *nrminv = sqrt(tmp);
1090 *resid = abs(*mingma) * *nrminv;
1091 *rqcorr = *mingma * tmp;