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_n1 = -1;
516 static integer c__0 = 0;
517 static integer c__1 = 1;
519 /* > \brief \b SGERFSX */
521 /* =========== DOCUMENTATION =========== */
523 /* Online html documentation available at */
524 /* http://www.netlib.org/lapack/explore-html/ */
527 /* > Download SGERFSX + dependencies */
528 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/sgerfsx
531 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/sgerfsx
534 /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/sgerfsx
542 /* SUBROUTINE SGERFSX( TRANS, EQUED, N, NRHS, A, LDA, AF, LDAF, IPIV, */
543 /* R, C, B, LDB, X, LDX, RCOND, BERR, N_ERR_BNDS, */
544 /* ERR_BNDS_NORM, ERR_BNDS_COMP, NPARAMS, PARAMS, */
545 /* WORK, IWORK, INFO ) */
547 /* CHARACTER TRANS, EQUED */
548 /* INTEGER INFO, LDA, LDAF, LDB, LDX, N, NRHS, NPARAMS, */
551 /* INTEGER IPIV( * ), IWORK( * ) */
552 /* REAL A( LDA, * ), AF( LDAF, * ), B( LDB, * ), */
553 /* $ X( LDX , * ), WORK( * ) */
554 /* REAL R( * ), C( * ), PARAMS( * ), BERR( * ), */
555 /* $ ERR_BNDS_NORM( NRHS, * ), */
556 /* $ ERR_BNDS_COMP( NRHS, * ) */
559 /* > \par Purpose: */
564 /* > SGERFSX improves the computed solution to a system of linear */
565 /* > equations and provides error bounds and backward error estimates */
566 /* > for the solution. In addition to normwise error bound, the code */
567 /* > provides maximum componentwise error bound if possible. See */
568 /* > comments for ERR_BNDS_NORM and ERR_BNDS_COMP for details of the */
569 /* > error bounds. */
571 /* > The original system of linear equations may have been equilibrated */
572 /* > before calling this routine, as described by arguments EQUED, R */
573 /* > and C below. In this case, the solution and error bounds returned */
574 /* > are for the original unequilibrated system. */
581 /* > Some optional parameters are bundled in the PARAMS array. These */
582 /* > settings determine how refinement is performed, but often the */
583 /* > defaults are acceptable. If the defaults are acceptable, users */
584 /* > can pass NPARAMS = 0 which prevents the source code from accessing */
585 /* > the PARAMS argument. */
588 /* > \param[in] TRANS */
590 /* > TRANS is CHARACTER*1 */
591 /* > Specifies the form of the system of equations: */
592 /* > = 'N': A * X = B (No transpose) */
593 /* > = 'T': A**T * X = B (Transpose) */
594 /* > = 'C': A**H * X = B (Conjugate transpose = Transpose) */
597 /* > \param[in] EQUED */
599 /* > EQUED is CHARACTER*1 */
600 /* > Specifies the form of equilibration that was done to A */
601 /* > before calling this routine. This is needed to compute */
602 /* > the solution and error bounds correctly. */
603 /* > = 'N': No equilibration */
604 /* > = 'R': Row equilibration, i.e., A has been premultiplied by */
606 /* > = 'C': Column equilibration, i.e., A has been postmultiplied */
608 /* > = 'B': Both row and column equilibration, i.e., A has been */
609 /* > replaced by diag(R) * A * diag(C). */
610 /* > The right hand side B has been changed accordingly. */
616 /* > The order of the matrix A. N >= 0. */
619 /* > \param[in] NRHS */
621 /* > NRHS is INTEGER */
622 /* > The number of right hand sides, i.e., the number of columns */
623 /* > of the matrices B and X. NRHS >= 0. */
628 /* > A is REAL array, dimension (LDA,N) */
629 /* > The original N-by-N matrix A. */
632 /* > \param[in] LDA */
634 /* > LDA is INTEGER */
635 /* > The leading dimension of the array A. LDA >= f2cmax(1,N). */
638 /* > \param[in] AF */
640 /* > AF is REAL array, dimension (LDAF,N) */
641 /* > The factors L and U from the factorization A = P*L*U */
642 /* > as computed by SGETRF. */
645 /* > \param[in] LDAF */
647 /* > LDAF is INTEGER */
648 /* > The leading dimension of the array AF. LDAF >= f2cmax(1,N). */
651 /* > \param[in] IPIV */
653 /* > IPIV is INTEGER array, dimension (N) */
654 /* > The pivot indices from SGETRF; for 1<=i<=N, row i of the */
655 /* > matrix was interchanged with row IPIV(i). */
660 /* > R is REAL array, dimension (N) */
661 /* > The row scale factors for A. If EQUED = 'R' or 'B', A is */
662 /* > multiplied on the left by diag(R); if EQUED = 'N' or 'C', R */
663 /* > is not accessed. */
664 /* > If R is accessed, each element of R should be a power of the radix */
665 /* > to ensure a reliable solution and error estimates. Scaling by */
666 /* > powers of the radix does not cause rounding errors unless the */
667 /* > result underflows or overflows. Rounding errors during scaling */
668 /* > lead to refining with a matrix that is not equivalent to the */
669 /* > input matrix, producing error estimates that may not be */
675 /* > C is REAL array, dimension (N) */
676 /* > The column scale factors for A. If EQUED = 'C' or 'B', A is */
677 /* > multiplied on the right by diag(C); if EQUED = 'N' or 'R', C */
678 /* > is not accessed. */
679 /* > If C is accessed, each element of C should be a power of the radix */
680 /* > to ensure a reliable solution and error estimates. Scaling by */
681 /* > powers of the radix does not cause rounding errors unless the */
682 /* > result underflows or overflows. Rounding errors during scaling */
683 /* > lead to refining with a matrix that is not equivalent to the */
684 /* > input matrix, producing error estimates that may not be */
690 /* > B is REAL array, dimension (LDB,NRHS) */
691 /* > The right hand side matrix B. */
694 /* > \param[in] LDB */
696 /* > LDB is INTEGER */
697 /* > The leading dimension of the array B. LDB >= f2cmax(1,N). */
700 /* > \param[in,out] X */
702 /* > X is REAL array, dimension (LDX,NRHS) */
703 /* > On entry, the solution matrix X, as computed by SGETRS. */
704 /* > On exit, the improved solution matrix X. */
707 /* > \param[in] LDX */
709 /* > LDX is INTEGER */
710 /* > The leading dimension of the array X. LDX >= f2cmax(1,N). */
713 /* > \param[out] RCOND */
715 /* > RCOND is REAL */
716 /* > Reciprocal scaled condition number. This is an estimate of the */
717 /* > reciprocal Skeel condition number of the matrix A after */
718 /* > equilibration (if done). If this is less than the machine */
719 /* > precision (in particular, if it is zero), the matrix is singular */
720 /* > to working precision. Note that the error may still be small even */
721 /* > if this number is very small and the matrix appears ill- */
725 /* > \param[out] BERR */
727 /* > BERR is REAL array, dimension (NRHS) */
728 /* > Componentwise relative backward error. This is the */
729 /* > componentwise relative backward error of each solution vector X(j) */
730 /* > (i.e., the smallest relative change in any element of A or B that */
731 /* > makes X(j) an exact solution). */
734 /* > \param[in] N_ERR_BNDS */
736 /* > N_ERR_BNDS is INTEGER */
737 /* > Number of error bounds to return for each right hand side */
738 /* > and each type (normwise or componentwise). See ERR_BNDS_NORM and */
739 /* > ERR_BNDS_COMP below. */
742 /* > \param[out] ERR_BNDS_NORM */
744 /* > ERR_BNDS_NORM is REAL array, dimension (NRHS, N_ERR_BNDS) */
745 /* > For each right-hand side, this array contains information about */
746 /* > various error bounds and condition numbers corresponding to the */
747 /* > normwise relative error, which is defined as follows: */
749 /* > Normwise relative error in the ith solution vector: */
750 /* > max_j (abs(XTRUE(j,i) - X(j,i))) */
751 /* > ------------------------------ */
752 /* > max_j abs(X(j,i)) */
754 /* > The array is indexed by the type of error information as described */
755 /* > below. There currently are up to three pieces of information */
758 /* > The first index in ERR_BNDS_NORM(i,:) corresponds to the ith */
759 /* > right-hand side. */
761 /* > The second index in ERR_BNDS_NORM(:,err) contains the following */
762 /* > three fields: */
763 /* > err = 1 "Trust/don't trust" boolean. Trust the answer if the */
764 /* > reciprocal condition number is less than the threshold */
765 /* > sqrt(n) * slamch('Epsilon'). */
767 /* > err = 2 "Guaranteed" error bound: The estimated forward error, */
768 /* > almost certainly within a factor of 10 of the true error */
769 /* > so long as the next entry is greater than the threshold */
770 /* > sqrt(n) * slamch('Epsilon'). This error bound should only */
771 /* > be trusted if the previous boolean is true. */
773 /* > err = 3 Reciprocal condition number: Estimated normwise */
774 /* > reciprocal condition number. Compared with the threshold */
775 /* > sqrt(n) * slamch('Epsilon') to determine if the error */
776 /* > estimate is "guaranteed". These reciprocal condition */
777 /* > numbers are 1 / (norm(Z^{-1},inf) * norm(Z,inf)) for some */
778 /* > appropriately scaled matrix Z. */
779 /* > Let Z = S*A, where S scales each row by a power of the */
780 /* > radix so all absolute row sums of Z are approximately 1. */
782 /* > See Lapack Working Note 165 for further details and extra */
786 /* > \param[out] ERR_BNDS_COMP */
788 /* > ERR_BNDS_COMP is REAL array, dimension (NRHS, N_ERR_BNDS) */
789 /* > For each right-hand side, this array contains information about */
790 /* > various error bounds and condition numbers corresponding to the */
791 /* > componentwise relative error, which is defined as follows: */
793 /* > Componentwise relative error in the ith solution vector: */
794 /* > abs(XTRUE(j,i) - X(j,i)) */
795 /* > max_j ---------------------- */
798 /* > The array is indexed by the right-hand side i (on which the */
799 /* > componentwise relative error depends), and the type of error */
800 /* > information as described below. There currently are up to three */
801 /* > pieces of information returned for each right-hand side. If */
802 /* > componentwise accuracy is not requested (PARAMS(3) = 0.0), then */
803 /* > ERR_BNDS_COMP is not accessed. If N_ERR_BNDS < 3, then at most */
804 /* > the first (:,N_ERR_BNDS) entries are returned. */
806 /* > The first index in ERR_BNDS_COMP(i,:) corresponds to the ith */
807 /* > right-hand side. */
809 /* > The second index in ERR_BNDS_COMP(:,err) contains the following */
810 /* > three fields: */
811 /* > err = 1 "Trust/don't trust" boolean. Trust the answer if the */
812 /* > reciprocal condition number is less than the threshold */
813 /* > sqrt(n) * slamch('Epsilon'). */
815 /* > err = 2 "Guaranteed" error bound: The estimated forward error, */
816 /* > almost certainly within a factor of 10 of the true error */
817 /* > so long as the next entry is greater than the threshold */
818 /* > sqrt(n) * slamch('Epsilon'). This error bound should only */
819 /* > be trusted if the previous boolean is true. */
821 /* > err = 3 Reciprocal condition number: Estimated componentwise */
822 /* > reciprocal condition number. Compared with the threshold */
823 /* > sqrt(n) * slamch('Epsilon') to determine if the error */
824 /* > estimate is "guaranteed". These reciprocal condition */
825 /* > numbers are 1 / (norm(Z^{-1},inf) * norm(Z,inf)) for some */
826 /* > appropriately scaled matrix Z. */
827 /* > Let Z = S*(A*diag(x)), where x is the solution for the */
828 /* > current right-hand side and S scales each row of */
829 /* > A*diag(x) by a power of the radix so all absolute row */
830 /* > sums of Z are approximately 1. */
832 /* > See Lapack Working Note 165 for further details and extra */
836 /* > \param[in] NPARAMS */
838 /* > NPARAMS is INTEGER */
839 /* > Specifies the number of parameters set in PARAMS. If <= 0, the */
840 /* > PARAMS array is never referenced and default values are used. */
843 /* > \param[in,out] PARAMS */
845 /* > PARAMS is REAL array, dimension NPARAMS */
846 /* > Specifies algorithm parameters. If an entry is < 0.0, then */
847 /* > that entry will be filled with default value used for that */
848 /* > parameter. Only positions up to NPARAMS are accessed; defaults */
849 /* > are used for higher-numbered parameters. */
851 /* > PARAMS(LA_LINRX_ITREF_I = 1) : Whether to perform iterative */
852 /* > refinement or not. */
854 /* > = 0.0: No refinement is performed, and no error bounds are */
856 /* > = 1.0: Use the double-precision refinement algorithm, */
857 /* > possibly with doubled-single computations if the */
858 /* > compilation environment does not support DOUBLE */
860 /* > (other values are reserved for future use) */
862 /* > PARAMS(LA_LINRX_ITHRESH_I = 2) : Maximum number of residual */
863 /* > computations allowed for refinement. */
865 /* > Aggressive: Set to 100 to permit convergence using approximate */
866 /* > factorizations or factorizations other than LU. If */
867 /* > the factorization uses a technique other than */
868 /* > Gaussian elimination, the guarantees in */
869 /* > err_bnds_norm and err_bnds_comp may no longer be */
872 /* > PARAMS(LA_LINRX_CWISE_I = 3) : Flag determining if the code */
873 /* > will attempt to find a solution with small componentwise */
874 /* > relative error in the double-precision algorithm. Positive */
875 /* > is true, 0.0 is false. */
876 /* > Default: 1.0 (attempt componentwise convergence) */
879 /* > \param[out] WORK */
881 /* > WORK is REAL array, dimension (4*N) */
884 /* > \param[out] IWORK */
886 /* > IWORK is INTEGER array, dimension (N) */
889 /* > \param[out] INFO */
891 /* > INFO is INTEGER */
892 /* > = 0: Successful exit. The solution to every right-hand side is */
894 /* > < 0: If INFO = -i, the i-th argument had an illegal value */
895 /* > > 0 and <= N: U(INFO,INFO) is exactly zero. The factorization */
896 /* > has been completed, but the factor U is exactly singular, so */
897 /* > the solution and error bounds could not be computed. RCOND = 0 */
899 /* > = N+J: The solution corresponding to the Jth right-hand side is */
900 /* > not guaranteed. The solutions corresponding to other right- */
901 /* > hand sides K with K > J may not be guaranteed as well, but */
902 /* > only the first such right-hand side is reported. If a small */
903 /* > componentwise error is not requested (PARAMS(3) = 0.0) then */
904 /* > the Jth right-hand side is the first with a normwise error */
905 /* > bound that is not guaranteed (the smallest J such */
906 /* > that ERR_BNDS_NORM(J,1) = 0.0). By default (PARAMS(3) = 1.0) */
907 /* > the Jth right-hand side is the first with either a normwise or */
908 /* > componentwise error bound that is not guaranteed (the smallest */
909 /* > J such that either ERR_BNDS_NORM(J,1) = 0.0 or */
910 /* > ERR_BNDS_COMP(J,1) = 0.0). See the definition of */
911 /* > ERR_BNDS_NORM(:,1) and ERR_BNDS_COMP(:,1). To get information */
912 /* > about all of the right-hand sides check ERR_BNDS_NORM or */
913 /* > ERR_BNDS_COMP. */
919 /* > \author Univ. of Tennessee */
920 /* > \author Univ. of California Berkeley */
921 /* > \author Univ. of Colorado Denver */
922 /* > \author NAG Ltd. */
924 /* > \date December 2016 */
926 /* > \ingroup realGEcomputational */
928 /* ===================================================================== */
929 /* Subroutine */ int sgerfsx_(char *trans, char *equed, integer *n, integer *
930 nrhs, real *a, integer *lda, real *af, integer *ldaf, integer *ipiv,
931 real *r__, real *c__, real *b, integer *ldb, real *x, integer *ldx,
932 real *rcond, real *berr, integer *n_err_bnds__, real *err_bnds_norm__,
933 real *err_bnds_comp__, integer *nparams, real *params, real *work,
934 integer *iwork, integer *info)
936 /* System generated locals */
937 integer a_dim1, a_offset, af_dim1, af_offset, b_dim1, b_offset, x_dim1,
938 x_offset, err_bnds_norm_dim1, err_bnds_norm_offset,
939 err_bnds_comp_dim1, err_bnds_comp_offset, i__1;
942 /* Local variables */
943 real illrcond_thresh__, unstable_thresh__;
944 extern /* Subroutine */ int sla_gerfsx_extended_(integer *, integer *,
945 integer *, integer *, real *, integer *, real *, integer *,
946 integer *, logical *, real *, real *, integer *, real *, integer *
947 , real *, integer *, real *, real *, real *, real *, real *, real
948 *, real *, integer *, real *, real *, logical *, integer *);
952 extern integer ilatrans_(char *);
953 logical ignore_cwise__;
955 extern logical lsame_(char *, char *);
956 real anorm, rcond_tmp__;
958 extern real slamch_(char *), slange_(char *, integer *, integer *,
959 real *, integer *, real *);
960 extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen), sgecon_(
961 char *, integer *, real *, integer *, real *, real *, real *,
962 integer *, integer *);
963 logical colequ, notran, rowequ;
964 integer trans_type__;
965 extern integer ilaprec_(char *);
966 extern real sla_gercond_(char *, integer *, real *, integer *, real *,
967 integer *, integer *, integer *, real *, integer *, real *,
969 integer ithresh, n_norms__;
970 real rthresh, cwise_wrong__;
973 /* -- LAPACK computational routine (version 3.7.0) -- */
974 /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
975 /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
979 /* ================================================================== */
982 /* Check the input parameters. */
984 /* Parameter adjustments */
985 err_bnds_comp_dim1 = *nrhs;
986 err_bnds_comp_offset = 1 + err_bnds_comp_dim1 * 1;
987 err_bnds_comp__ -= err_bnds_comp_offset;
988 err_bnds_norm_dim1 = *nrhs;
989 err_bnds_norm_offset = 1 + err_bnds_norm_dim1 * 1;
990 err_bnds_norm__ -= err_bnds_norm_offset;
992 a_offset = 1 + a_dim1 * 1;
995 af_offset = 1 + af_dim1 * 1;
1001 b_offset = 1 + b_dim1 * 1;
1004 x_offset = 1 + x_dim1 * 1;
1013 trans_type__ = ilatrans_(trans);
1015 if (*nparams >= 1) {
1016 if (params[1] < 0.f) {
1019 ref_type__ = params[1];
1023 /* Set default parameters. */
1025 illrcond_thresh__ = (real) (*n) * slamch_("Epsilon");
1028 unstable_thresh__ = .25f;
1029 ignore_cwise__ = FALSE_;
1031 if (*nparams >= 2) {
1032 if (params[2] < 0.f) {
1033 params[2] = (real) ithresh;
1035 ithresh = (integer) params[2];
1038 if (*nparams >= 3) {
1039 if (params[3] < 0.f) {
1040 if (ignore_cwise__) {
1046 ignore_cwise__ = params[3] == 0.f;
1049 if (ref_type__ == 0 || *n_err_bnds__ == 0) {
1051 } else if (ignore_cwise__) {
1057 notran = lsame_(trans, "N");
1058 rowequ = lsame_(equed, "R") || lsame_(equed, "B");
1059 colequ = lsame_(equed, "C") || lsame_(equed, "B");
1061 /* Test input parameters. */
1063 if (trans_type__ == -1) {
1065 } else if (! rowequ && ! colequ && ! lsame_(equed, "N")) {
1067 } else if (*n < 0) {
1069 } else if (*nrhs < 0) {
1071 } else if (*lda < f2cmax(1,*n)) {
1073 } else if (*ldaf < f2cmax(1,*n)) {
1075 } else if (*ldb < f2cmax(1,*n)) {
1077 } else if (*ldx < f2cmax(1,*n)) {
1082 xerbla_("SGERFSX", &i__1, (ftnlen)7);
1086 /* Quick return if possible. */
1088 if (*n == 0 || *nrhs == 0) {
1091 for (j = 1; j <= i__1; ++j) {
1093 if (*n_err_bnds__ >= 1) {
1094 err_bnds_norm__[j + err_bnds_norm_dim1] = 1.f;
1095 err_bnds_comp__[j + err_bnds_comp_dim1] = 1.f;
1097 if (*n_err_bnds__ >= 2) {
1098 err_bnds_norm__[j + (err_bnds_norm_dim1 << 1)] = 0.f;
1099 err_bnds_comp__[j + (err_bnds_comp_dim1 << 1)] = 0.f;
1101 if (*n_err_bnds__ >= 3) {
1102 err_bnds_norm__[j + err_bnds_norm_dim1 * 3] = 1.f;
1103 err_bnds_comp__[j + err_bnds_comp_dim1 * 3] = 1.f;
1109 /* Default to failure. */
1113 for (j = 1; j <= i__1; ++j) {
1115 if (*n_err_bnds__ >= 1) {
1116 err_bnds_norm__[j + err_bnds_norm_dim1] = 1.f;
1117 err_bnds_comp__[j + err_bnds_comp_dim1] = 1.f;
1119 if (*n_err_bnds__ >= 2) {
1120 err_bnds_norm__[j + (err_bnds_norm_dim1 << 1)] = 1.f;
1121 err_bnds_comp__[j + (err_bnds_comp_dim1 << 1)] = 1.f;
1123 if (*n_err_bnds__ >= 3) {
1124 err_bnds_norm__[j + err_bnds_norm_dim1 * 3] = 0.f;
1125 err_bnds_comp__[j + err_bnds_comp_dim1 * 3] = 0.f;
1129 /* Compute the norm of A and the reciprocal of the condition */
1133 *(unsigned char *)norm = 'I';
1135 *(unsigned char *)norm = '1';
1137 anorm = slange_(norm, n, n, &a[a_offset], lda, &work[1]);
1138 sgecon_(norm, n, &af[af_offset], ldaf, &anorm, rcond, &work[1], &iwork[1],
1141 /* Perform refinement on each right-hand side */
1143 if (ref_type__ != 0) {
1144 prec_type__ = ilaprec_("D");
1146 sla_gerfsx_extended_(&prec_type__, &trans_type__, n, nrhs, &a[
1147 a_offset], lda, &af[af_offset], ldaf, &ipiv[1], &colequ, &
1148 c__[1], &b[b_offset], ldb, &x[x_offset], ldx, &berr[1], &
1149 n_norms__, &err_bnds_norm__[err_bnds_norm_offset], &
1150 err_bnds_comp__[err_bnds_comp_offset], &work[*n + 1], &
1151 work[1], &work[(*n << 1) + 1], &work[1], rcond, &ithresh,
1152 &rthresh, &unstable_thresh__, &ignore_cwise__, info);
1154 sla_gerfsx_extended_(&prec_type__, &trans_type__, n, nrhs, &a[
1155 a_offset], lda, &af[af_offset], ldaf, &ipiv[1], &rowequ, &
1156 r__[1], &b[b_offset], ldb, &x[x_offset], ldx, &berr[1], &
1157 n_norms__, &err_bnds_norm__[err_bnds_norm_offset], &
1158 err_bnds_comp__[err_bnds_comp_offset], &work[*n + 1], &
1159 work[1], &work[(*n << 1) + 1], &work[1], rcond, &ithresh,
1160 &rthresh, &unstable_thresh__, &ignore_cwise__, info);
1164 r__1 = 10.f, r__2 = sqrt((real) (*n));
1165 err_lbnd__ = f2cmax(r__1,r__2) * slamch_("Epsilon");
1166 if (*n_err_bnds__ >= 1 && n_norms__ >= 1) {
1168 /* Compute scaled normwise condition number cond(A*C). */
1170 if (colequ && notran) {
1171 rcond_tmp__ = sla_gercond_(trans, n, &a[a_offset], lda, &af[
1172 af_offset], ldaf, &ipiv[1], &c_n1, &c__[1], info, &work[1]
1174 } else if (rowequ && ! notran) {
1175 rcond_tmp__ = sla_gercond_(trans, n, &a[a_offset], lda, &af[
1176 af_offset], ldaf, &ipiv[1], &c_n1, &r__[1], info, &work[1]
1179 rcond_tmp__ = sla_gercond_(trans, n, &a[a_offset], lda, &af[
1180 af_offset], ldaf, &ipiv[1], &c__0, &r__[1], info, &work[1]
1184 for (j = 1; j <= i__1; ++j) {
1186 /* Cap the error at 1.0. */
1188 if (*n_err_bnds__ >= 2 && err_bnds_norm__[j + (err_bnds_norm_dim1
1190 err_bnds_norm__[j + (err_bnds_norm_dim1 << 1)] = 1.f;
1193 /* Threshold the error (see LAWN). */
1195 if (rcond_tmp__ < illrcond_thresh__) {
1196 err_bnds_norm__[j + (err_bnds_norm_dim1 << 1)] = 1.f;
1197 err_bnds_norm__[j + err_bnds_norm_dim1] = 0.f;
1201 } else if (err_bnds_norm__[j + (err_bnds_norm_dim1 << 1)] <
1203 err_bnds_norm__[j + (err_bnds_norm_dim1 << 1)] = err_lbnd__;
1204 err_bnds_norm__[j + err_bnds_norm_dim1] = 1.f;
1207 /* Save the condition number. */
1209 if (*n_err_bnds__ >= 3) {
1210 err_bnds_norm__[j + err_bnds_norm_dim1 * 3] = rcond_tmp__;
1214 if (*n_err_bnds__ >= 1 && n_norms__ >= 2) {
1216 /* Compute componentwise condition number cond(A*diag(Y(:,J))) for */
1217 /* each right-hand side using the current solution as an estimate of */
1218 /* the true solution. If the componentwise error estimate is too */
1219 /* large, then the solution is a lousy estimate of truth and the */
1220 /* estimated RCOND may be too optimistic. To avoid misleading users, */
1221 /* the inverse condition number is set to 0.0 when the estimated */
1222 /* cwise error is at least CWISE_WRONG. */
1224 cwise_wrong__ = sqrt(slamch_("Epsilon"));
1226 for (j = 1; j <= i__1; ++j) {
1227 if (err_bnds_comp__[j + (err_bnds_comp_dim1 << 1)] <
1229 rcond_tmp__ = sla_gercond_(trans, n, &a[a_offset], lda, &af[
1230 af_offset], ldaf, &ipiv[1], &c__1, &x[j * x_dim1 + 1],
1231 info, &work[1], &iwork[1]);
1236 /* Cap the error at 1.0. */
1238 if (*n_err_bnds__ >= 2 && err_bnds_comp__[j + (err_bnds_comp_dim1
1240 err_bnds_comp__[j + (err_bnds_comp_dim1 << 1)] = 1.f;
1243 /* Threshold the error (see LAWN). */
1245 if (rcond_tmp__ < illrcond_thresh__) {
1246 err_bnds_comp__[j + (err_bnds_comp_dim1 << 1)] = 1.f;
1247 err_bnds_comp__[j + err_bnds_comp_dim1] = 0.f;
1248 if (params[3] == 1.f && *info < *n + j) {
1251 } else if (err_bnds_comp__[j + (err_bnds_comp_dim1 << 1)] <
1253 err_bnds_comp__[j + (err_bnds_comp_dim1 << 1)] = err_lbnd__;
1254 err_bnds_comp__[j + err_bnds_comp_dim1] = 1.f;
1257 /* Save the condition number. */
1259 if (*n_err_bnds__ >= 3) {
1260 err_bnds_comp__[j + err_bnds_comp_dim1 * 3] = rcond_tmp__;
1267 /* End of SGERFSX */