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 integer c__2 = 2;
517 static real c_b28 = 1.f;
519 /* > \brief \b STGSEN */
521 /* =========== DOCUMENTATION =========== */
523 /* Online html documentation available at */
524 /* http://www.netlib.org/lapack/explore-html/ */
527 /* > Download STGSEN + dependencies */
528 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/stgsen.
531 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/stgsen.
534 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/stgsen.
542 /* SUBROUTINE STGSEN( IJOB, WANTQ, WANTZ, SELECT, N, A, LDA, B, LDB, */
543 /* ALPHAR, ALPHAI, BETA, Q, LDQ, Z, LDZ, M, PL, */
544 /* PR, DIF, WORK, LWORK, IWORK, LIWORK, INFO ) */
546 /* LOGICAL WANTQ, WANTZ */
547 /* INTEGER IJOB, INFO, LDA, LDB, LDQ, LDZ, LIWORK, LWORK, */
550 /* LOGICAL SELECT( * ) */
551 /* INTEGER IWORK( * ) */
552 /* REAL A( LDA, * ), ALPHAI( * ), ALPHAR( * ), */
553 /* $ B( LDB, * ), BETA( * ), DIF( * ), Q( LDQ, * ), */
554 /* $ WORK( * ), Z( LDZ, * ) */
557 /* > \par Purpose: */
562 /* > STGSEN reorders the generalized real Schur decomposition of a real */
563 /* > matrix pair (A, B) (in terms of an orthonormal equivalence trans- */
564 /* > formation Q**T * (A, B) * Z), so that a selected cluster of eigenvalues */
565 /* > appears in the leading diagonal blocks of the upper quasi-triangular */
566 /* > matrix A and the upper triangular B. The leading columns of Q and */
567 /* > Z form orthonormal bases of the corresponding left and right eigen- */
568 /* > spaces (deflating subspaces). (A, B) must be in generalized real */
569 /* > Schur canonical form (as returned by SGGES), i.e. A is block upper */
570 /* > triangular with 1-by-1 and 2-by-2 diagonal blocks. B is upper */
573 /* > STGSEN also computes the generalized eigenvalues */
575 /* > w(j) = (ALPHAR(j) + i*ALPHAI(j))/BETA(j) */
577 /* > of the reordered matrix pair (A, B). */
579 /* > Optionally, STGSEN computes the estimates of reciprocal condition */
580 /* > numbers for eigenvalues and eigenspaces. These are Difu[(A11,B11), */
581 /* > (A22,B22)] and Difl[(A11,B11), (A22,B22)], i.e. the separation(s) */
582 /* > between the matrix pairs (A11, B11) and (A22,B22) that correspond to */
583 /* > the selected cluster and the eigenvalues outside the cluster, resp., */
584 /* > and norms of "projections" onto left and right eigenspaces w.r.t. */
585 /* > the selected cluster in the (1,1)-block. */
591 /* > \param[in] IJOB */
593 /* > IJOB is INTEGER */
594 /* > Specifies whether condition numbers are required for the */
595 /* > cluster of eigenvalues (PL and PR) or the deflating subspaces */
596 /* > (Difu and Difl): */
597 /* > =0: Only reorder w.r.t. SELECT. No extras. */
598 /* > =1: Reciprocal of norms of "projections" onto left and right */
599 /* > eigenspaces w.r.t. the selected cluster (PL and PR). */
600 /* > =2: Upper bounds on Difu and Difl. F-norm-based estimate */
602 /* > =3: Estimate of Difu and Difl. 1-norm-based estimate */
604 /* > About 5 times as expensive as IJOB = 2. */
605 /* > =4: Compute PL, PR and DIF (i.e. 0, 1 and 2 above): Economic */
606 /* > version to get it all. */
607 /* > =5: Compute PL, PR and DIF (i.e. 0, 1 and 3 above) */
610 /* > \param[in] WANTQ */
612 /* > WANTQ is LOGICAL */
613 /* > .TRUE. : update the left transformation matrix Q; */
614 /* > .FALSE.: do not update Q. */
617 /* > \param[in] WANTZ */
619 /* > WANTZ is LOGICAL */
620 /* > .TRUE. : update the right transformation matrix Z; */
621 /* > .FALSE.: do not update Z. */
624 /* > \param[in] SELECT */
626 /* > SELECT is LOGICAL array, dimension (N) */
627 /* > SELECT specifies the eigenvalues in the selected cluster. */
628 /* > To select a real eigenvalue w(j), SELECT(j) must be set to */
629 /* > .TRUE.. To select a complex conjugate pair of eigenvalues */
630 /* > w(j) and w(j+1), corresponding to a 2-by-2 diagonal block, */
631 /* > either SELECT(j) or SELECT(j+1) or both must be set to */
632 /* > .TRUE.; a complex conjugate pair of eigenvalues must be */
633 /* > either both included in the cluster or both excluded. */
639 /* > The order of the matrices A and B. N >= 0. */
642 /* > \param[in,out] A */
644 /* > A is REAL array, dimension(LDA,N) */
645 /* > On entry, the upper quasi-triangular matrix A, with (A, B) in */
646 /* > generalized real Schur canonical form. */
647 /* > On exit, A is overwritten by the reordered matrix A. */
650 /* > \param[in] LDA */
652 /* > LDA is INTEGER */
653 /* > The leading dimension of the array A. LDA >= f2cmax(1,N). */
656 /* > \param[in,out] B */
658 /* > B is REAL array, dimension(LDB,N) */
659 /* > On entry, the upper triangular matrix B, with (A, B) in */
660 /* > generalized real Schur canonical form. */
661 /* > On exit, B is overwritten by the reordered matrix B. */
664 /* > \param[in] LDB */
666 /* > LDB is INTEGER */
667 /* > The leading dimension of the array B. LDB >= f2cmax(1,N). */
670 /* > \param[out] ALPHAR */
672 /* > ALPHAR is REAL array, dimension (N) */
675 /* > \param[out] ALPHAI */
677 /* > ALPHAI is REAL array, dimension (N) */
680 /* > \param[out] BETA */
682 /* > BETA is REAL array, dimension (N) */
684 /* > On exit, (ALPHAR(j) + ALPHAI(j)*i)/BETA(j), j=1,...,N, will */
685 /* > be the generalized eigenvalues. ALPHAR(j) + ALPHAI(j)*i */
686 /* > and BETA(j),j=1,...,N are the diagonals of the complex Schur */
687 /* > form (S,T) that would result if the 2-by-2 diagonal blocks of */
688 /* > the real generalized Schur form of (A,B) were further reduced */
689 /* > to triangular form using complex unitary transformations. */
690 /* > If ALPHAI(j) is zero, then the j-th eigenvalue is real; if */
691 /* > positive, then the j-th and (j+1)-st eigenvalues are a */
692 /* > complex conjugate pair, with ALPHAI(j+1) negative. */
695 /* > \param[in,out] Q */
697 /* > Q is REAL array, dimension (LDQ,N) */
698 /* > On entry, if WANTQ = .TRUE., Q is an N-by-N matrix. */
699 /* > On exit, Q has been postmultiplied by the left orthogonal */
700 /* > transformation matrix which reorder (A, B); The leading M */
701 /* > columns of Q form orthonormal bases for the specified pair of */
702 /* > left eigenspaces (deflating subspaces). */
703 /* > If WANTQ = .FALSE., Q is not referenced. */
706 /* > \param[in] LDQ */
708 /* > LDQ is INTEGER */
709 /* > The leading dimension of the array Q. LDQ >= 1; */
710 /* > and if WANTQ = .TRUE., LDQ >= N. */
713 /* > \param[in,out] Z */
715 /* > Z is REAL array, dimension (LDZ,N) */
716 /* > On entry, if WANTZ = .TRUE., Z is an N-by-N matrix. */
717 /* > On exit, Z has been postmultiplied by the left orthogonal */
718 /* > transformation matrix which reorder (A, B); The leading M */
719 /* > columns of Z form orthonormal bases for the specified pair of */
720 /* > left eigenspaces (deflating subspaces). */
721 /* > If WANTZ = .FALSE., Z is not referenced. */
724 /* > \param[in] LDZ */
726 /* > LDZ is INTEGER */
727 /* > The leading dimension of the array Z. LDZ >= 1; */
728 /* > If WANTZ = .TRUE., LDZ >= N. */
731 /* > \param[out] M */
734 /* > The dimension of the specified pair of left and right eigen- */
735 /* > spaces (deflating subspaces). 0 <= M <= N. */
738 /* > \param[out] PL */
743 /* > \param[out] PR */
747 /* > If IJOB = 1, 4 or 5, PL, PR are lower bounds on the */
748 /* > reciprocal of the norm of "projections" onto left and right */
749 /* > eigenspaces with respect to the selected cluster. */
750 /* > 0 < PL, PR <= 1. */
751 /* > If M = 0 or M = N, PL = PR = 1. */
752 /* > If IJOB = 0, 2 or 3, PL and PR are not referenced. */
755 /* > \param[out] DIF */
757 /* > DIF is REAL array, dimension (2). */
758 /* > If IJOB >= 2, DIF(1:2) store the estimates of Difu and Difl. */
759 /* > If IJOB = 2 or 4, DIF(1:2) are F-norm-based upper bounds on */
760 /* > Difu and Difl. If IJOB = 3 or 5, DIF(1:2) are 1-norm-based */
761 /* > estimates of Difu and Difl. */
762 /* > If M = 0 or N, DIF(1:2) = F-norm([A, B]). */
763 /* > If IJOB = 0 or 1, DIF is not referenced. */
766 /* > \param[out] WORK */
768 /* > WORK is REAL array, dimension (MAX(1,LWORK)) */
769 /* > On exit, if INFO = 0, WORK(1) returns the optimal LWORK. */
772 /* > \param[in] LWORK */
774 /* > LWORK is INTEGER */
775 /* > The dimension of the array WORK. LWORK >= 4*N+16. */
776 /* > If IJOB = 1, 2 or 4, LWORK >= MAX(4*N+16, 2*M*(N-M)). */
777 /* > If IJOB = 3 or 5, LWORK >= MAX(4*N+16, 4*M*(N-M)). */
779 /* > If LWORK = -1, then a workspace query is assumed; the routine */
780 /* > only calculates the optimal size of the WORK array, returns */
781 /* > this value as the first entry of the WORK array, and no error */
782 /* > message related to LWORK is issued by XERBLA. */
785 /* > \param[out] IWORK */
787 /* > IWORK is INTEGER array, dimension (MAX(1,LIWORK)) */
788 /* > On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK. */
791 /* > \param[in] LIWORK */
793 /* > LIWORK is INTEGER */
794 /* > The dimension of the array IWORK. LIWORK >= 1. */
795 /* > If IJOB = 1, 2 or 4, LIWORK >= N+6. */
796 /* > If IJOB = 3 or 5, LIWORK >= MAX(2*M*(N-M), N+6). */
798 /* > If LIWORK = -1, then a workspace query is assumed; the */
799 /* > routine only calculates the optimal size of the IWORK array, */
800 /* > returns this value as the first entry of the IWORK array, and */
801 /* > no error message related to LIWORK is issued by XERBLA. */
804 /* > \param[out] INFO */
806 /* > INFO is INTEGER */
807 /* > =0: Successful exit. */
808 /* > <0: If INFO = -i, the i-th argument had an illegal value. */
809 /* > =1: Reordering of (A, B) failed because the transformed */
810 /* > matrix pair (A, B) would be too far from generalized */
811 /* > Schur form; the problem is very ill-conditioned. */
812 /* > (A, B) may have been partially reordered. */
813 /* > If requested, 0 is returned in DIF(*), PL and PR. */
819 /* > \author Univ. of Tennessee */
820 /* > \author Univ. of California Berkeley */
821 /* > \author Univ. of Colorado Denver */
822 /* > \author NAG Ltd. */
824 /* > \date June 2016 */
826 /* > \ingroup realOTHERcomputational */
828 /* > \par Further Details: */
829 /* ===================== */
833 /* > STGSEN first collects the selected eigenvalues by computing */
834 /* > orthogonal U and W that move them to the top left corner of (A, B). */
835 /* > In other words, the selected eigenvalues are the eigenvalues of */
836 /* > (A11, B11) in: */
838 /* > U**T*(A, B)*W = (A11 A12) (B11 B12) n1 */
839 /* > ( 0 A22),( 0 B22) n2 */
842 /* > where N = n1+n2 and U**T means the transpose of U. The first n1 columns */
843 /* > of U and W span the specified pair of left and right eigenspaces */
844 /* > (deflating subspaces) of (A, B). */
846 /* > If (A, B) has been obtained from the generalized real Schur */
847 /* > decomposition of a matrix pair (C, D) = Q*(A, B)*Z**T, then the */
848 /* > reordered generalized real Schur form of (C, D) is given by */
850 /* > (C, D) = (Q*U)*(U**T*(A, B)*W)*(Z*W)**T, */
852 /* > and the first n1 columns of Q*U and Z*W span the corresponding */
853 /* > deflating subspaces of (C, D) (Q and Z store Q*U and Z*W, resp.). */
855 /* > Note that if the selected eigenvalue is sufficiently ill-conditioned, */
856 /* > then its value may differ significantly from its value before */
859 /* > The reciprocal condition numbers of the left and right eigenspaces */
860 /* > spanned by the first n1 columns of U and W (or Q*U and Z*W) may */
861 /* > be returned in DIF(1:2), corresponding to Difu and Difl, resp. */
863 /* > The Difu and Difl are defined as: */
865 /* > Difu[(A11, B11), (A22, B22)] = sigma-f2cmin( Zu ) */
867 /* > Difl[(A11, B11), (A22, B22)] = Difu[(A22, B22), (A11, B11)], */
869 /* > where sigma-f2cmin(Zu) is the smallest singular value of the */
870 /* > (2*n1*n2)-by-(2*n1*n2) matrix */
872 /* > Zu = [ kron(In2, A11) -kron(A22**T, In1) ] */
873 /* > [ kron(In2, B11) -kron(B22**T, In1) ]. */
875 /* > Here, Inx is the identity matrix of size nx and A22**T is the */
876 /* > transpose of A22. kron(X, Y) is the Kronecker product between */
877 /* > the matrices X and Y. */
879 /* > When DIF(2) is small, small changes in (A, B) can cause large changes */
880 /* > in the deflating subspace. An approximate (asymptotic) bound on the */
881 /* > maximum angular error in the computed deflating subspaces is */
883 /* > EPS * norm((A, B)) / DIF(2), */
885 /* > where EPS is the machine precision. */
887 /* > The reciprocal norm of the projectors on the left and right */
888 /* > eigenspaces associated with (A11, B11) may be returned in PL and PR. */
889 /* > They are computed as follows. First we compute L and R so that */
890 /* > P*(A, B)*Q is block diagonal, where */
892 /* > P = ( I -L ) n1 Q = ( I R ) n1 */
893 /* > ( 0 I ) n2 and ( 0 I ) n2 */
896 /* > and (L, R) is the solution to the generalized Sylvester equation */
898 /* > A11*R - L*A22 = -A12 */
899 /* > B11*R - L*B22 = -B12 */
901 /* > Then PL = (F-norm(L)**2+1)**(-1/2) and PR = (F-norm(R)**2+1)**(-1/2). */
902 /* > An approximate (asymptotic) bound on the average absolute error of */
903 /* > the selected eigenvalues is */
905 /* > EPS * norm((A, B)) / PL. */
907 /* > There are also global error bounds which valid for perturbations up */
908 /* > to a certain restriction: A lower bound (x) on the smallest */
909 /* > F-norm(E,F) for which an eigenvalue of (A11, B11) may move and */
910 /* > coalesce with an eigenvalue of (A22, B22) under perturbation (E,F), */
911 /* > (i.e. (A + E, B + F), is */
913 /* > x = f2cmin(Difu,Difl)/((1/(PL*PL)+1/(PR*PR))**(1/2)+2*f2cmax(1/PL,1/PR)). */
915 /* > An approximate bound on x can be computed from DIF(1:2), PL and PR. */
917 /* > If y = ( F-norm(E,F) / x) <= 1, the angles between the perturbed */
918 /* > (L', R') and unperturbed (L, R) left and right deflating subspaces */
919 /* > associated with the selected cluster in the (1,1)-blocks can be */
922 /* > f2cmax-angle(L, L') <= arctan( y * PL / (1 - y * (1 - PL * PL)**(1/2)) */
923 /* > f2cmax-angle(R, R') <= arctan( y * PR / (1 - y * (1 - PR * PR)**(1/2)) */
925 /* > See LAPACK User's Guide section 4.11 or the following references */
926 /* > for more information. */
928 /* > Note that if the default method for computing the Frobenius-norm- */
929 /* > based estimate DIF is not wanted (see SLATDF), then the parameter */
930 /* > IDIFJB (see below) should be changed from 3 to 4 (routine SLATDF */
931 /* > (IJOB = 2 will be used)). See STGSYL for more details. */
934 /* > \par Contributors: */
935 /* ================== */
937 /* > Bo Kagstrom and Peter Poromaa, Department of Computing Science, */
938 /* > Umea University, S-901 87 Umea, Sweden. */
940 /* > \par References: */
941 /* ================ */
945 /* > [1] B. Kagstrom; A Direct Method for Reordering Eigenvalues in the */
946 /* > Generalized Real Schur Form of a Regular Matrix Pair (A, B), in */
947 /* > M.S. Moonen et al (eds), Linear Algebra for Large Scale and */
948 /* > Real-Time Applications, Kluwer Academic Publ. 1993, pp 195-218. */
950 /* > [2] B. Kagstrom and P. Poromaa; Computing Eigenspaces with Specified */
951 /* > Eigenvalues of a Regular Matrix Pair (A, B) and Condition */
952 /* > Estimation: Theory, Algorithms and Software, */
953 /* > Report UMINF - 94.04, Department of Computing Science, Umea */
954 /* > University, S-901 87 Umea, Sweden, 1994. Also as LAPACK Working */
955 /* > Note 87. To appear in Numerical Algorithms, 1996. */
957 /* > [3] B. Kagstrom and P. Poromaa, LAPACK-Style Algorithms and Software */
958 /* > for Solving the Generalized Sylvester Equation and Estimating the */
959 /* > Separation between Regular Matrix Pairs, Report UMINF - 93.23, */
960 /* > Department of Computing Science, Umea University, S-901 87 Umea, */
961 /* > Sweden, December 1993, Revised April 1994, Also as LAPACK Working */
962 /* > Note 75. To appear in ACM Trans. on Math. Software, Vol 22, No 1, */
966 /* ===================================================================== */
967 /* Subroutine */ int stgsen_(integer *ijob, logical *wantq, logical *wantz,
968 logical *select, integer *n, real *a, integer *lda, real *b, integer *
969 ldb, real *alphar, real *alphai, real *beta, real *q, integer *ldq,
970 real *z__, integer *ldz, integer *m, real *pl, real *pr, real *dif,
971 real *work, integer *lwork, integer *iwork, integer *liwork, integer *
974 /* System generated locals */
975 integer a_dim1, a_offset, b_dim1, b_offset, q_dim1, q_offset, z_dim1,
976 z_offset, i__1, i__2;
979 /* Local variables */
985 extern /* Subroutine */ int slag2_(real *, integer *, real *, integer *,
986 real *, real *, real *, real *, real *, real *);
987 integer i__, k, isave[3];
992 extern /* Subroutine */ int slacn2_(integer *, real *, real *, integer *,
993 real *, integer *, integer *);
994 logical wantd1, wantd2;
999 extern real slamch_(char *);
1000 extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen), slacpy_(
1001 char *, integer *, integer *, real *, integer *, real *, integer *
1002 ), stgexc_(logical *, logical *, integer *, real *,
1003 integer *, real *, integer *, real *, integer *, real *, integer *
1004 , integer *, integer *, real *, integer *, integer *);
1006 extern /* Subroutine */ int slassq_(integer *, real *, integer *, real *,
1011 extern /* Subroutine */ int stgsyl_(char *, integer *, integer *, integer
1012 *, real *, integer *, real *, integer *, real *, integer *, real *
1013 , integer *, real *, integer *, real *, integer *, real *, real *,
1014 real *, integer *, integer *, integer *);
1019 /* -- LAPACK computational routine (version 3.7.0) -- */
1020 /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
1021 /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
1025 /* ===================================================================== */
1028 /* Decode and test the input parameters */
1030 /* Parameter adjustments */
1033 a_offset = 1 + a_dim1 * 1;
1036 b_offset = 1 + b_dim1 * 1;
1042 q_offset = 1 + q_dim1 * 1;
1045 z_offset = 1 + z_dim1 * 1;
1053 lquery = *lwork == -1 || *liwork == -1;
1055 if (*ijob < 0 || *ijob > 5) {
1057 } else if (*n < 0) {
1059 } else if (*lda < f2cmax(1,*n)) {
1061 } else if (*ldb < f2cmax(1,*n)) {
1063 } else if (*ldq < 1 || *wantq && *ldq < *n) {
1065 } else if (*ldz < 1 || *wantz && *ldz < *n) {
1071 xerbla_("STGSEN", &i__1, (ftnlen)6);
1075 /* Get machine constants */
1078 smlnum = slamch_("S") / eps;
1081 wantp = *ijob == 1 || *ijob >= 4;
1082 wantd1 = *ijob == 2 || *ijob == 4;
1083 wantd2 = *ijob == 3 || *ijob == 5;
1084 wantd = wantd1 || wantd2;
1086 /* Set M to the dimension of the specified pair of deflating */
1091 if (! lquery || *ijob != 0) {
1093 for (k = 1; k <= i__1; ++k) {
1098 if (a[k + 1 + k * a_dim1] == 0.f) {
1104 if (select[k] || select[k + 1]) {
1118 if (*ijob == 1 || *ijob == 2 || *ijob == 4) {
1120 i__1 = 1, i__2 = (*n << 2) + 16, i__1 = f2cmax(i__1,i__2), i__2 = (*m <<
1122 lwmin = f2cmax(i__1,i__2);
1124 i__1 = 1, i__2 = *n + 6;
1125 liwmin = f2cmax(i__1,i__2);
1126 } else if (*ijob == 3 || *ijob == 5) {
1128 i__1 = 1, i__2 = (*n << 2) + 16, i__1 = f2cmax(i__1,i__2), i__2 = (*m <<
1130 lwmin = f2cmax(i__1,i__2);
1132 i__1 = 1, i__2 = (*m << 1) * (*n - *m), i__1 = f2cmax(i__1,i__2), i__2 =
1134 liwmin = f2cmax(i__1,i__2);
1137 i__1 = 1, i__2 = (*n << 2) + 16;
1138 lwmin = f2cmax(i__1,i__2);
1142 work[1] = (real) lwmin;
1145 if (*lwork < lwmin && ! lquery) {
1147 } else if (*liwork < liwmin && ! lquery) {
1153 xerbla_("STGSEN", &i__1, (ftnlen)6);
1155 } else if (lquery) {
1159 /* Quick return if possible. */
1161 if (*m == *n || *m == 0) {
1170 for (i__ = 1; i__ <= i__1; ++i__) {
1171 slassq_(n, &a[i__ * a_dim1 + 1], &c__1, &dscale, &dsum);
1172 slassq_(n, &b[i__ * b_dim1 + 1], &c__1, &dscale, &dsum);
1175 dif[1] = dscale * sqrt(dsum);
1181 /* Collect the selected blocks at the top-left corner of (A, B). */
1186 for (k = 1; k <= i__1; ++k) {
1193 if (a[k + 1 + k * a_dim1] != 0.f) {
1195 swap = swap || select[k + 1];
1202 /* Swap the K-th block to position KS. */
1203 /* Perform the reordering of diagonal blocks in (A, B) */
1204 /* by orthogonal transformation matrices and update */
1205 /* Q and Z accordingly (if requested): */
1209 stgexc_(wantq, wantz, n, &a[a_offset], lda, &b[b_offset],
1210 ldb, &q[q_offset], ldq, &z__[z_offset], ldz, &kk,
1211 &ks, &work[1], lwork, &ierr);
1216 /* Swap is rejected: exit. */
1239 /* Solve generalized Sylvester equation for R and L */
1240 /* and compute PL and PR. */
1246 slacpy_("Full", &n1, &n2, &a[i__ * a_dim1 + 1], lda, &work[1], &n1);
1247 slacpy_("Full", &n1, &n2, &b[i__ * b_dim1 + 1], ldb, &work[n1 * n2 +
1249 i__1 = *lwork - (n1 << 1) * n2;
1250 stgsyl_("N", &ijb, &n1, &n2, &a[a_offset], lda, &a[i__ + i__ * a_dim1]
1251 , lda, &work[1], &n1, &b[b_offset], ldb, &b[i__ + i__ *
1252 b_dim1], ldb, &work[n1 * n2 + 1], &n1, &dscale, &dif[1], &
1253 work[(n1 * n2 << 1) + 1], &i__1, &iwork[1], &ierr);
1255 /* Estimate the reciprocal of norms of "projections" onto left */
1256 /* and right eigenspaces. */
1261 slassq_(&i__1, &work[1], &c__1, &rdscal, &dsum);
1262 *pl = rdscal * sqrt(dsum);
1266 *pl = dscale / (sqrt(dscale * dscale / *pl + *pl) * sqrt(*pl));
1271 slassq_(&i__1, &work[n1 * n2 + 1], &c__1, &rdscal, &dsum);
1272 *pr = rdscal * sqrt(dsum);
1276 *pr = dscale / (sqrt(dscale * dscale / *pr + *pr) * sqrt(*pr));
1282 /* Compute estimates of Difu and Difl. */
1290 /* Frobenius norm-based Difu-estimate. */
1292 i__1 = *lwork - (n1 << 1) * n2;
1293 stgsyl_("N", &ijb, &n1, &n2, &a[a_offset], lda, &a[i__ + i__ *
1294 a_dim1], lda, &work[1], &n1, &b[b_offset], ldb, &b[i__ +
1295 i__ * b_dim1], ldb, &work[n1 * n2 + 1], &n1, &dscale, &
1296 dif[1], &work[(n1 << 1) * n2 + 1], &i__1, &iwork[1], &
1299 /* Frobenius norm-based Difl-estimate. */
1301 i__1 = *lwork - (n1 << 1) * n2;
1302 stgsyl_("N", &ijb, &n2, &n1, &a[i__ + i__ * a_dim1], lda, &a[
1303 a_offset], lda, &work[1], &n2, &b[i__ + i__ * b_dim1],
1304 ldb, &b[b_offset], ldb, &work[n1 * n2 + 1], &n2, &dscale,
1305 &dif[2], &work[(n1 << 1) * n2 + 1], &i__1, &iwork[1], &
1310 /* Compute 1-norm-based estimates of Difu and Difl using */
1311 /* reversed communication with SLACN2. In each step a */
1312 /* generalized Sylvester equation or a transposed variant */
1320 mn2 = (n1 << 1) * n2;
1322 /* 1-norm-based estimate of Difu. */
1325 slacn2_(&mn2, &work[mn2 + 1], &work[1], &iwork[1], &dif[1], &kase,
1330 /* Solve generalized Sylvester equation. */
1332 i__1 = *lwork - (n1 << 1) * n2;
1333 stgsyl_("N", &ijb, &n1, &n2, &a[a_offset], lda, &a[i__ +
1334 i__ * a_dim1], lda, &work[1], &n1, &b[b_offset],
1335 ldb, &b[i__ + i__ * b_dim1], ldb, &work[n1 * n2 +
1336 1], &n1, &dscale, &dif[1], &work[(n1 << 1) * n2 +
1337 1], &i__1, &iwork[1], &ierr);
1340 /* Solve the transposed variant. */
1342 i__1 = *lwork - (n1 << 1) * n2;
1343 stgsyl_("T", &ijb, &n1, &n2, &a[a_offset], lda, &a[i__ +
1344 i__ * a_dim1], lda, &work[1], &n1, &b[b_offset],
1345 ldb, &b[i__ + i__ * b_dim1], ldb, &work[n1 * n2 +
1346 1], &n1, &dscale, &dif[1], &work[(n1 << 1) * n2 +
1347 1], &i__1, &iwork[1], &ierr);
1351 dif[1] = dscale / dif[1];
1353 /* 1-norm-based estimate of Difl. */
1356 slacn2_(&mn2, &work[mn2 + 1], &work[1], &iwork[1], &dif[2], &kase,
1361 /* Solve generalized Sylvester equation. */
1363 i__1 = *lwork - (n1 << 1) * n2;
1364 stgsyl_("N", &ijb, &n2, &n1, &a[i__ + i__ * a_dim1], lda,
1365 &a[a_offset], lda, &work[1], &n2, &b[i__ + i__ *
1366 b_dim1], ldb, &b[b_offset], ldb, &work[n1 * n2 +
1367 1], &n2, &dscale, &dif[2], &work[(n1 << 1) * n2 +
1368 1], &i__1, &iwork[1], &ierr);
1371 /* Solve the transposed variant. */
1373 i__1 = *lwork - (n1 << 1) * n2;
1374 stgsyl_("T", &ijb, &n2, &n1, &a[i__ + i__ * a_dim1], lda,
1375 &a[a_offset], lda, &work[1], &n2, &b[i__ + i__ *
1376 b_dim1], ldb, &b[b_offset], ldb, &work[n1 * n2 +
1377 1], &n2, &dscale, &dif[2], &work[(n1 << 1) * n2 +
1378 1], &i__1, &iwork[1], &ierr);
1382 dif[2] = dscale / dif[2];
1389 /* Compute generalized eigenvalues of reordered pair (A, B) and */
1390 /* normalize the generalized Schur form. */
1394 for (k = 1; k <= i__1; ++k) {
1400 if (a[k + 1 + k * a_dim1] != 0.f) {
1407 /* Compute the eigenvalue(s) at position K. */
1409 work[1] = a[k + k * a_dim1];
1410 work[2] = a[k + 1 + k * a_dim1];
1411 work[3] = a[k + (k + 1) * a_dim1];
1412 work[4] = a[k + 1 + (k + 1) * a_dim1];
1413 work[5] = b[k + k * b_dim1];
1414 work[6] = b[k + 1 + k * b_dim1];
1415 work[7] = b[k + (k + 1) * b_dim1];
1416 work[8] = b[k + 1 + (k + 1) * b_dim1];
1417 r__1 = smlnum * eps;
1418 slag2_(&work[1], &c__2, &work[5], &c__2, &r__1, &beta[k], &
1419 beta[k + 1], &alphar[k], &alphar[k + 1], &alphai[k]);
1420 alphai[k + 1] = -alphai[k];
1424 if (r_sign(&c_b28, &b[k + k * b_dim1]) < 0.f) {
1426 /* If B(K,K) is negative, make it positive */
1429 for (i__ = 1; i__ <= i__2; ++i__) {
1430 a[k + i__ * a_dim1] = -a[k + i__ * a_dim1];
1431 b[k + i__ * b_dim1] = -b[k + i__ * b_dim1];
1433 q[i__ + k * q_dim1] = -q[i__ + k * q_dim1];
1439 alphar[k] = a[k + k * a_dim1];
1441 beta[k] = b[k + k * b_dim1];
1448 work[1] = (real) lwmin;