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chbtrd.c 34 kB

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  1. /* f2c.h -- Standard Fortran to C header file */
  2. /** barf [ba:rf] 2. "He suggested using FORTRAN, and everybody barfed."
  3. - From The Shogakukan DICTIONARY OF NEW ENGLISH (Second edition) */
  4. #ifndef F2C_INCLUDE
  5. #define F2C_INCLUDE
  6. #include <math.h>
  7. #include <stdlib.h>
  8. #include <string.h>
  9. #include <stdio.h>
  10. #include <complex.h>
  11. #ifdef complex
  12. #undef complex
  13. #endif
  14. #ifdef I
  15. #undef I
  16. #endif
  17. typedef int integer;
  18. typedef unsigned int uinteger;
  19. typedef char *address;
  20. typedef short int shortint;
  21. typedef float real;
  22. typedef double doublereal;
  23. typedef struct { real r, i; } complex;
  24. typedef struct { doublereal r, i; } doublecomplex;
  25. static inline _Complex float Cf(complex *z) {return z->r + z->i*_Complex_I;}
  26. static inline _Complex double Cd(doublecomplex *z) {return z->r + z->i*_Complex_I;}
  27. static inline _Complex float * _pCf(complex *z) {return (_Complex float*)z;}
  28. static inline _Complex double * _pCd(doublecomplex *z) {return (_Complex double*)z;}
  29. #define pCf(z) (*_pCf(z))
  30. #define pCd(z) (*_pCd(z))
  31. typedef int logical;
  32. typedef short int shortlogical;
  33. typedef char logical1;
  34. typedef char integer1;
  35. #define TRUE_ (1)
  36. #define FALSE_ (0)
  37. /* Extern is for use with -E */
  38. #ifndef Extern
  39. #define Extern extern
  40. #endif
  41. /* I/O stuff */
  42. typedef int flag;
  43. typedef int ftnlen;
  44. typedef int ftnint;
  45. /*external read, write*/
  46. typedef struct
  47. { flag cierr;
  48. ftnint ciunit;
  49. flag ciend;
  50. char *cifmt;
  51. ftnint cirec;
  52. } cilist;
  53. /*internal read, write*/
  54. typedef struct
  55. { flag icierr;
  56. char *iciunit;
  57. flag iciend;
  58. char *icifmt;
  59. ftnint icirlen;
  60. ftnint icirnum;
  61. } icilist;
  62. /*open*/
  63. typedef struct
  64. { flag oerr;
  65. ftnint ounit;
  66. char *ofnm;
  67. ftnlen ofnmlen;
  68. char *osta;
  69. char *oacc;
  70. char *ofm;
  71. ftnint orl;
  72. char *oblnk;
  73. } olist;
  74. /*close*/
  75. typedef struct
  76. { flag cerr;
  77. ftnint cunit;
  78. char *csta;
  79. } cllist;
  80. /*rewind, backspace, endfile*/
  81. typedef struct
  82. { flag aerr;
  83. ftnint aunit;
  84. } alist;
  85. /* inquire */
  86. typedef struct
  87. { flag inerr;
  88. ftnint inunit;
  89. char *infile;
  90. ftnlen infilen;
  91. ftnint *inex; /*parameters in standard's order*/
  92. ftnint *inopen;
  93. ftnint *innum;
  94. ftnint *innamed;
  95. char *inname;
  96. ftnlen innamlen;
  97. char *inacc;
  98. ftnlen inacclen;
  99. char *inseq;
  100. ftnlen inseqlen;
  101. char *indir;
  102. ftnlen indirlen;
  103. char *infmt;
  104. ftnlen infmtlen;
  105. char *inform;
  106. ftnint informlen;
  107. char *inunf;
  108. ftnlen inunflen;
  109. ftnint *inrecl;
  110. ftnint *innrec;
  111. char *inblank;
  112. ftnlen inblanklen;
  113. } inlist;
  114. #define VOID void
  115. union Multitype { /* for multiple entry points */
  116. integer1 g;
  117. shortint h;
  118. integer i;
  119. /* longint j; */
  120. real r;
  121. doublereal d;
  122. complex c;
  123. doublecomplex z;
  124. };
  125. typedef union Multitype Multitype;
  126. struct Vardesc { /* for Namelist */
  127. char *name;
  128. char *addr;
  129. ftnlen *dims;
  130. int type;
  131. };
  132. typedef struct Vardesc Vardesc;
  133. struct Namelist {
  134. char *name;
  135. Vardesc **vars;
  136. int nvars;
  137. };
  138. typedef struct Namelist Namelist;
  139. #define abs(x) ((x) >= 0 ? (x) : -(x))
  140. #define dabs(x) (fabs(x))
  141. #define f2cmin(a,b) ((a) <= (b) ? (a) : (b))
  142. #define f2cmax(a,b) ((a) >= (b) ? (a) : (b))
  143. #define dmin(a,b) (f2cmin(a,b))
  144. #define dmax(a,b) (f2cmax(a,b))
  145. #define bit_test(a,b) ((a) >> (b) & 1)
  146. #define bit_clear(a,b) ((a) & ~((uinteger)1 << (b)))
  147. #define bit_set(a,b) ((a) | ((uinteger)1 << (b)))
  148. #define abort_() { sig_die("Fortran abort routine called", 1); }
  149. #define c_abs(z) (cabsf(Cf(z)))
  150. #define c_cos(R,Z) { pCf(R)=ccos(Cf(Z)); }
  151. #define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
  152. #define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
  153. #define c_exp(R, Z) {pCf(R) = cexpf(Cf(Z));}
  154. #define c_log(R, Z) {pCf(R) = clogf(Cf(Z));}
  155. #define c_sin(R, Z) {pCf(R) = csinf(Cf(Z));}
  156. //#define c_sqrt(R, Z) {*(R) = csqrtf(Cf(Z));}
  157. #define c_sqrt(R, Z) {pCf(R) = csqrtf(Cf(Z));}
  158. #define d_abs(x) (fabs(*(x)))
  159. #define d_acos(x) (acos(*(x)))
  160. #define d_asin(x) (asin(*(x)))
  161. #define d_atan(x) (atan(*(x)))
  162. #define d_atn2(x, y) (atan2(*(x),*(y)))
  163. #define d_cnjg(R, Z) { pCd(R) = conj(Cd(Z)); }
  164. #define r_cnjg(R, Z) { pCf(R) = conj(Cf(Z)); }
  165. #define d_cos(x) (cos(*(x)))
  166. #define d_cosh(x) (cosh(*(x)))
  167. #define d_dim(__a, __b) ( *(__a) > *(__b) ? *(__a) - *(__b) : 0.0 )
  168. #define d_exp(x) (exp(*(x)))
  169. #define d_imag(z) (cimag(Cd(z)))
  170. #define r_imag(z) (cimag(Cf(z)))
  171. #define d_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
  172. #define r_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
  173. #define d_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
  174. #define r_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
  175. #define d_log(x) (log(*(x)))
  176. #define d_mod(x, y) (fmod(*(x), *(y)))
  177. #define u_nint(__x) ((__x)>=0 ? floor((__x) + .5) : -floor(.5 - (__x)))
  178. #define d_nint(x) u_nint(*(x))
  179. #define u_sign(__a,__b) ((__b) >= 0 ? ((__a) >= 0 ? (__a) : -(__a)) : -((__a) >= 0 ? (__a) : -(__a)))
  180. #define d_sign(a,b) u_sign(*(a),*(b))
  181. #define r_sign(a,b) u_sign(*(a),*(b))
  182. #define d_sin(x) (sin(*(x)))
  183. #define d_sinh(x) (sinh(*(x)))
  184. #define d_sqrt(x) (sqrt(*(x)))
  185. #define d_tan(x) (tan(*(x)))
  186. #define d_tanh(x) (tanh(*(x)))
  187. #define i_abs(x) abs(*(x))
  188. #define i_dnnt(x) ((integer)u_nint(*(x)))
  189. #define i_len(s, n) (n)
  190. #define i_nint(x) ((integer)u_nint(*(x)))
  191. #define i_sign(a,b) ((integer)u_sign((integer)*(a),(integer)*(b)))
  192. #define pow_dd(ap, bp) ( pow(*(ap), *(bp)))
  193. #define pow_si(B,E) spow_ui(*(B),*(E))
  194. #define pow_ri(B,E) spow_ui(*(B),*(E))
  195. #define pow_di(B,E) dpow_ui(*(B),*(E))
  196. #define pow_zi(p, a, b) {pCd(p) = zpow_ui(Cd(a), *(b));}
  197. #define pow_ci(p, a, b) {pCf(p) = cpow_ui(Cf(a), *(b));}
  198. #define pow_zz(R,A,B) {pCd(R) = cpow(Cd(A),*(B));}
  199. #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++ = ' '; }
  200. #define s_cmp(a,b,c,d) ((integer)strncmp((a),(b),f2cmin((c),(d))))
  201. #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]; }
  202. #define sig_die(s, kill) { exit(1); }
  203. #define s_stop(s, n) {exit(0);}
  204. static char junk[] = "\n@(#)LIBF77 VERSION 19990503\n";
  205. #define z_abs(z) (cabs(Cd(z)))
  206. #define z_exp(R, Z) {pCd(R) = cexp(Cd(Z));}
  207. #define z_sqrt(R, Z) {pCd(R) = csqrt(Cd(Z));}
  208. #define myexit_() break;
  209. #define mycycle() continue;
  210. #define myceiling(w) {ceil(w)}
  211. #define myhuge(w) {HUGE_VAL}
  212. //#define mymaxloc_(w,s,e,n) {if (sizeof(*(w)) == sizeof(double)) dmaxloc_((w),*(s),*(e),n); else dmaxloc_((w),*(s),*(e),n);}
  213. #define mymaxloc(w,s,e,n) {dmaxloc_(w,*(s),*(e),n)}
  214. /* procedure parameter types for -A and -C++ */
  215. #define F2C_proc_par_types 1
  216. #ifdef __cplusplus
  217. typedef logical (*L_fp)(...);
  218. #else
  219. typedef logical (*L_fp)();
  220. #endif
  221. static float spow_ui(float x, integer n) {
  222. float pow=1.0; unsigned long int u;
  223. if(n != 0) {
  224. if(n < 0) n = -n, x = 1/x;
  225. for(u = n; ; ) {
  226. if(u & 01) pow *= x;
  227. if(u >>= 1) x *= x;
  228. else break;
  229. }
  230. }
  231. return pow;
  232. }
  233. static double dpow_ui(double x, integer n) {
  234. double pow=1.0; unsigned long int u;
  235. if(n != 0) {
  236. if(n < 0) n = -n, x = 1/x;
  237. for(u = n; ; ) {
  238. if(u & 01) pow *= x;
  239. if(u >>= 1) x *= x;
  240. else break;
  241. }
  242. }
  243. return pow;
  244. }
  245. static _Complex float cpow_ui(_Complex float x, integer n) {
  246. _Complex float pow=1.0; unsigned long int u;
  247. if(n != 0) {
  248. if(n < 0) n = -n, x = 1/x;
  249. for(u = n; ; ) {
  250. if(u & 01) pow *= x;
  251. if(u >>= 1) x *= x;
  252. else break;
  253. }
  254. }
  255. return pow;
  256. }
  257. static _Complex double zpow_ui(_Complex double x, integer n) {
  258. _Complex double pow=1.0; unsigned long int u;
  259. if(n != 0) {
  260. if(n < 0) n = -n, x = 1/x;
  261. for(u = n; ; ) {
  262. if(u & 01) pow *= x;
  263. if(u >>= 1) x *= x;
  264. else break;
  265. }
  266. }
  267. return pow;
  268. }
  269. static integer pow_ii(integer x, integer n) {
  270. integer pow; unsigned long int u;
  271. if (n <= 0) {
  272. if (n == 0 || x == 1) pow = 1;
  273. else if (x != -1) pow = x == 0 ? 1/x : 0;
  274. else n = -n;
  275. }
  276. if ((n > 0) || !(n == 0 || x == 1 || x != -1)) {
  277. u = n;
  278. for(pow = 1; ; ) {
  279. if(u & 01) pow *= x;
  280. if(u >>= 1) x *= x;
  281. else break;
  282. }
  283. }
  284. return pow;
  285. }
  286. static integer dmaxloc_(double *w, integer s, integer e, integer *n)
  287. {
  288. double m; integer i, mi;
  289. for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
  290. if (w[i-1]>m) mi=i ,m=w[i-1];
  291. return mi-s+1;
  292. }
  293. static integer smaxloc_(float *w, integer s, integer e, integer *n)
  294. {
  295. float m; integer i, mi;
  296. for(m=w[s-1], mi=s, i=s+1; i<=e; i++)
  297. if (w[i-1]>m) mi=i ,m=w[i-1];
  298. return mi-s+1;
  299. }
  300. static inline void cdotc_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
  301. integer n = *n_, incx = *incx_, incy = *incy_, i;
  302. _Complex float zdotc = 0.0;
  303. if (incx == 1 && incy == 1) {
  304. for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  305. zdotc += conjf(Cf(&x[i])) * Cf(&y[i]);
  306. }
  307. } else {
  308. for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  309. zdotc += conjf(Cf(&x[i*incx])) * Cf(&y[i*incy]);
  310. }
  311. }
  312. pCf(z) = zdotc;
  313. }
  314. static inline void zdotc_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
  315. integer n = *n_, incx = *incx_, incy = *incy_, i;
  316. _Complex double zdotc = 0.0;
  317. if (incx == 1 && incy == 1) {
  318. for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  319. zdotc += conj(Cd(&x[i])) * Cd(&y[i]);
  320. }
  321. } else {
  322. for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  323. zdotc += conj(Cd(&x[i*incx])) * Cd(&y[i*incy]);
  324. }
  325. }
  326. pCd(z) = zdotc;
  327. }
  328. static inline void cdotu_(complex *z, integer *n_, complex *x, integer *incx_, complex *y, integer *incy_) {
  329. integer n = *n_, incx = *incx_, incy = *incy_, i;
  330. _Complex float zdotc = 0.0;
  331. if (incx == 1 && incy == 1) {
  332. for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  333. zdotc += Cf(&x[i]) * Cf(&y[i]);
  334. }
  335. } else {
  336. for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  337. zdotc += Cf(&x[i*incx]) * Cf(&y[i*incy]);
  338. }
  339. }
  340. pCf(z) = zdotc;
  341. }
  342. static inline void zdotu_(doublecomplex *z, integer *n_, doublecomplex *x, integer *incx_, doublecomplex *y, integer *incy_) {
  343. integer n = *n_, incx = *incx_, incy = *incy_, i;
  344. _Complex double zdotc = 0.0;
  345. if (incx == 1 && incy == 1) {
  346. for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  347. zdotc += Cd(&x[i]) * Cd(&y[i]);
  348. }
  349. } else {
  350. for (i=0;i<n;i++) { /* zdotc = zdotc + dconjg(x(i))* y(i) */
  351. zdotc += Cd(&x[i*incx]) * Cd(&y[i*incy]);
  352. }
  353. }
  354. pCd(z) = zdotc;
  355. }
  356. #endif
  357. /* -- translated by f2c (version 20000121).
  358. You must link the resulting object file with the libraries:
  359. -lf2c -lm (in that order)
  360. */
  361. /* Table of constant values */
  362. static complex c_b1 = {0.f,0.f};
  363. static complex c_b2 = {1.f,0.f};
  364. static integer c__1 = 1;
  365. /* > \brief \b CHBTRD */
  366. /* =========== DOCUMENTATION =========== */
  367. /* Online html documentation available at */
  368. /* http://www.netlib.org/lapack/explore-html/ */
  369. /* > \htmlonly */
  370. /* > Download CHBTRD + dependencies */
  371. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/chbtrd.
  372. f"> */
  373. /* > [TGZ]</a> */
  374. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/chbtrd.
  375. f"> */
  376. /* > [ZIP]</a> */
  377. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/chbtrd.
  378. f"> */
  379. /* > [TXT]</a> */
  380. /* > \endhtmlonly */
  381. /* Definition: */
  382. /* =========== */
  383. /* SUBROUTINE CHBTRD( VECT, UPLO, N, KD, AB, LDAB, D, E, Q, LDQ, */
  384. /* WORK, INFO ) */
  385. /* CHARACTER UPLO, VECT */
  386. /* INTEGER INFO, KD, LDAB, LDQ, N */
  387. /* REAL D( * ), E( * ) */
  388. /* COMPLEX AB( LDAB, * ), Q( LDQ, * ), WORK( * ) */
  389. /* > \par Purpose: */
  390. /* ============= */
  391. /* > */
  392. /* > \verbatim */
  393. /* > */
  394. /* > CHBTRD reduces a complex Hermitian band matrix A to real symmetric */
  395. /* > tridiagonal form T by a unitary similarity transformation: */
  396. /* > Q**H * A * Q = T. */
  397. /* > \endverbatim */
  398. /* Arguments: */
  399. /* ========== */
  400. /* > \param[in] VECT */
  401. /* > \verbatim */
  402. /* > VECT is CHARACTER*1 */
  403. /* > = 'N': do not form Q; */
  404. /* > = 'V': form Q; */
  405. /* > = 'U': update a matrix X, by forming X*Q. */
  406. /* > \endverbatim */
  407. /* > */
  408. /* > \param[in] UPLO */
  409. /* > \verbatim */
  410. /* > UPLO is CHARACTER*1 */
  411. /* > = 'U': Upper triangle of A is stored; */
  412. /* > = 'L': Lower triangle of A is stored. */
  413. /* > \endverbatim */
  414. /* > */
  415. /* > \param[in] N */
  416. /* > \verbatim */
  417. /* > N is INTEGER */
  418. /* > The order of the matrix A. N >= 0. */
  419. /* > \endverbatim */
  420. /* > */
  421. /* > \param[in] KD */
  422. /* > \verbatim */
  423. /* > KD is INTEGER */
  424. /* > The number of superdiagonals of the matrix A if UPLO = 'U', */
  425. /* > or the number of subdiagonals if UPLO = 'L'. KD >= 0. */
  426. /* > \endverbatim */
  427. /* > */
  428. /* > \param[in,out] AB */
  429. /* > \verbatim */
  430. /* > AB is COMPLEX array, dimension (LDAB,N) */
  431. /* > On entry, the upper or lower triangle of the Hermitian band */
  432. /* > matrix A, stored in the first KD+1 rows of the array. The */
  433. /* > j-th column of A is stored in the j-th column of the array AB */
  434. /* > as follows: */
  435. /* > if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for f2cmax(1,j-kd)<=i<=j; */
  436. /* > if UPLO = 'L', AB(1+i-j,j) = A(i,j) for j<=i<=f2cmin(n,j+kd). */
  437. /* > On exit, the diagonal elements of AB are overwritten by the */
  438. /* > diagonal elements of the tridiagonal matrix T; if KD > 0, the */
  439. /* > elements on the first superdiagonal (if UPLO = 'U') or the */
  440. /* > first subdiagonal (if UPLO = 'L') are overwritten by the */
  441. /* > off-diagonal elements of T; the rest of AB is overwritten by */
  442. /* > values generated during the reduction. */
  443. /* > \endverbatim */
  444. /* > */
  445. /* > \param[in] LDAB */
  446. /* > \verbatim */
  447. /* > LDAB is INTEGER */
  448. /* > The leading dimension of the array AB. LDAB >= KD+1. */
  449. /* > \endverbatim */
  450. /* > */
  451. /* > \param[out] D */
  452. /* > \verbatim */
  453. /* > D is REAL array, dimension (N) */
  454. /* > The diagonal elements of the tridiagonal matrix T. */
  455. /* > \endverbatim */
  456. /* > */
  457. /* > \param[out] E */
  458. /* > \verbatim */
  459. /* > E is REAL array, dimension (N-1) */
  460. /* > The off-diagonal elements of the tridiagonal matrix T: */
  461. /* > E(i) = T(i,i+1) if UPLO = 'U'; E(i) = T(i+1,i) if UPLO = 'L'. */
  462. /* > \endverbatim */
  463. /* > */
  464. /* > \param[in,out] Q */
  465. /* > \verbatim */
  466. /* > Q is COMPLEX array, dimension (LDQ,N) */
  467. /* > On entry, if VECT = 'U', then Q must contain an N-by-N */
  468. /* > matrix X; if VECT = 'N' or 'V', then Q need not be set. */
  469. /* > */
  470. /* > On exit: */
  471. /* > if VECT = 'V', Q contains the N-by-N unitary matrix Q; */
  472. /* > if VECT = 'U', Q contains the product X*Q; */
  473. /* > if VECT = 'N', the array Q is not referenced. */
  474. /* > \endverbatim */
  475. /* > */
  476. /* > \param[in] LDQ */
  477. /* > \verbatim */
  478. /* > LDQ is INTEGER */
  479. /* > The leading dimension of the array Q. */
  480. /* > LDQ >= 1, and LDQ >= N if VECT = 'V' or 'U'. */
  481. /* > \endverbatim */
  482. /* > */
  483. /* > \param[out] WORK */
  484. /* > \verbatim */
  485. /* > WORK is COMPLEX array, dimension (N) */
  486. /* > \endverbatim */
  487. /* > */
  488. /* > \param[out] INFO */
  489. /* > \verbatim */
  490. /* > INFO is INTEGER */
  491. /* > = 0: successful exit */
  492. /* > < 0: if INFO = -i, the i-th argument had an illegal value */
  493. /* > \endverbatim */
  494. /* Authors: */
  495. /* ======== */
  496. /* > \author Univ. of Tennessee */
  497. /* > \author Univ. of California Berkeley */
  498. /* > \author Univ. of Colorado Denver */
  499. /* > \author NAG Ltd. */
  500. /* > \date December 2016 */
  501. /* > \ingroup complexOTHERcomputational */
  502. /* > \par Further Details: */
  503. /* ===================== */
  504. /* > */
  505. /* > \verbatim */
  506. /* > */
  507. /* > Modified by Linda Kaufman, Bell Labs. */
  508. /* > \endverbatim */
  509. /* > */
  510. /* ===================================================================== */
  511. /* Subroutine */ int chbtrd_(char *vect, char *uplo, integer *n, integer *kd,
  512. complex *ab, integer *ldab, real *d__, real *e, complex *q, integer *
  513. ldq, complex *work, integer *info)
  514. {
  515. /* System generated locals */
  516. integer ab_dim1, ab_offset, q_dim1, q_offset, i__1, i__2, i__3, i__4,
  517. i__5, i__6;
  518. real r__1;
  519. complex q__1;
  520. /* Local variables */
  521. integer inca, jend, lend, jinc;
  522. real abst;
  523. integer incx, last;
  524. complex temp;
  525. extern /* Subroutine */ int crot_(integer *, complex *, integer *,
  526. complex *, integer *, real *, complex *);
  527. integer j1end, j1inc, i__, j, k, l;
  528. complex t;
  529. extern /* Subroutine */ int cscal_(integer *, complex *, complex *,
  530. integer *);
  531. integer iqend;
  532. extern logical lsame_(char *, char *);
  533. logical initq, wantq, upper;
  534. integer i2, j1, j2;
  535. extern /* Subroutine */ int clar2v_(integer *, complex *, complex *,
  536. complex *, integer *, real *, complex *, integer *);
  537. integer nq, nr, iqaend;
  538. extern /* Subroutine */ int clacgv_(integer *, complex *, integer *),
  539. claset_(char *, integer *, integer *, complex *, complex *,
  540. complex *, integer *), clartg_(complex *, complex *, real
  541. *, complex *, complex *), xerbla_(char *, integer *, ftnlen),
  542. clargv_(integer *, complex *, integer *, complex *, integer *,
  543. real *, integer *), clartv_(integer *, complex *, integer *,
  544. complex *, integer *, real *, complex *, integer *);
  545. integer kd1, ibl, iqb, kdn, jin, nrt, kdm1;
  546. /* -- LAPACK computational routine (version 3.7.0) -- */
  547. /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
  548. /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
  549. /* December 2016 */
  550. /* ===================================================================== */
  551. /* Test the input parameters */
  552. /* Parameter adjustments */
  553. ab_dim1 = *ldab;
  554. ab_offset = 1 + ab_dim1 * 1;
  555. ab -= ab_offset;
  556. --d__;
  557. --e;
  558. q_dim1 = *ldq;
  559. q_offset = 1 + q_dim1 * 1;
  560. q -= q_offset;
  561. --work;
  562. /* Function Body */
  563. initq = lsame_(vect, "V");
  564. wantq = initq || lsame_(vect, "U");
  565. upper = lsame_(uplo, "U");
  566. kd1 = *kd + 1;
  567. kdm1 = *kd - 1;
  568. incx = *ldab - 1;
  569. iqend = 1;
  570. *info = 0;
  571. if (! wantq && ! lsame_(vect, "N")) {
  572. *info = -1;
  573. } else if (! upper && ! lsame_(uplo, "L")) {
  574. *info = -2;
  575. } else if (*n < 0) {
  576. *info = -3;
  577. } else if (*kd < 0) {
  578. *info = -4;
  579. } else if (*ldab < kd1) {
  580. *info = -6;
  581. } else if (*ldq < f2cmax(1,*n) && wantq) {
  582. *info = -10;
  583. }
  584. if (*info != 0) {
  585. i__1 = -(*info);
  586. xerbla_("CHBTRD", &i__1, (ftnlen)6);
  587. return 0;
  588. }
  589. /* Quick return if possible */
  590. if (*n == 0) {
  591. return 0;
  592. }
  593. /* Initialize Q to the unit matrix, if needed */
  594. if (initq) {
  595. claset_("Full", n, n, &c_b1, &c_b2, &q[q_offset], ldq);
  596. }
  597. /* Wherever possible, plane rotations are generated and applied in */
  598. /* vector operations of length NR over the index set J1:J2:KD1. */
  599. /* The real cosines and complex sines of the plane rotations are */
  600. /* stored in the arrays D and WORK. */
  601. inca = kd1 * *ldab;
  602. /* Computing MIN */
  603. i__1 = *n - 1;
  604. kdn = f2cmin(i__1,*kd);
  605. if (upper) {
  606. if (*kd > 1) {
  607. /* Reduce to complex Hermitian tridiagonal form, working with */
  608. /* the upper triangle */
  609. nr = 0;
  610. j1 = kdn + 2;
  611. j2 = 1;
  612. i__1 = kd1 + ab_dim1;
  613. i__2 = kd1 + ab_dim1;
  614. r__1 = ab[i__2].r;
  615. ab[i__1].r = r__1, ab[i__1].i = 0.f;
  616. i__1 = *n - 2;
  617. for (i__ = 1; i__ <= i__1; ++i__) {
  618. /* Reduce i-th row of matrix to tridiagonal form */
  619. for (k = kdn + 1; k >= 2; --k) {
  620. j1 += kdn;
  621. j2 += kdn;
  622. if (nr > 0) {
  623. /* generate plane rotations to annihilate nonzero */
  624. /* elements which have been created outside the band */
  625. clargv_(&nr, &ab[(j1 - 1) * ab_dim1 + 1], &inca, &
  626. work[j1], &kd1, &d__[j1], &kd1);
  627. /* apply rotations from the right */
  628. /* Dependent on the the number of diagonals either */
  629. /* CLARTV or CROT is used */
  630. if (nr >= (*kd << 1) - 1) {
  631. i__2 = *kd - 1;
  632. for (l = 1; l <= i__2; ++l) {
  633. clartv_(&nr, &ab[l + 1 + (j1 - 1) * ab_dim1],
  634. &inca, &ab[l + j1 * ab_dim1], &inca, &
  635. d__[j1], &work[j1], &kd1);
  636. /* L10: */
  637. }
  638. } else {
  639. jend = j1 + (nr - 1) * kd1;
  640. i__2 = jend;
  641. i__3 = kd1;
  642. for (jinc = j1; i__3 < 0 ? jinc >= i__2 : jinc <=
  643. i__2; jinc += i__3) {
  644. crot_(&kdm1, &ab[(jinc - 1) * ab_dim1 + 2], &
  645. c__1, &ab[jinc * ab_dim1 + 1], &c__1,
  646. &d__[jinc], &work[jinc]);
  647. /* L20: */
  648. }
  649. }
  650. }
  651. if (k > 2) {
  652. if (k <= *n - i__ + 1) {
  653. /* generate plane rotation to annihilate a(i,i+k-1) */
  654. /* within the band */
  655. clartg_(&ab[*kd - k + 3 + (i__ + k - 2) * ab_dim1]
  656. , &ab[*kd - k + 2 + (i__ + k - 1) *
  657. ab_dim1], &d__[i__ + k - 1], &work[i__ +
  658. k - 1], &temp);
  659. i__3 = *kd - k + 3 + (i__ + k - 2) * ab_dim1;
  660. ab[i__3].r = temp.r, ab[i__3].i = temp.i;
  661. /* apply rotation from the right */
  662. i__3 = k - 3;
  663. crot_(&i__3, &ab[*kd - k + 4 + (i__ + k - 2) *
  664. ab_dim1], &c__1, &ab[*kd - k + 3 + (i__ +
  665. k - 1) * ab_dim1], &c__1, &d__[i__ + k -
  666. 1], &work[i__ + k - 1]);
  667. }
  668. ++nr;
  669. j1 = j1 - kdn - 1;
  670. }
  671. /* apply plane rotations from both sides to diagonal */
  672. /* blocks */
  673. if (nr > 0) {
  674. clar2v_(&nr, &ab[kd1 + (j1 - 1) * ab_dim1], &ab[kd1 +
  675. j1 * ab_dim1], &ab[*kd + j1 * ab_dim1], &inca,
  676. &d__[j1], &work[j1], &kd1);
  677. }
  678. /* apply plane rotations from the left */
  679. if (nr > 0) {
  680. clacgv_(&nr, &work[j1], &kd1);
  681. if ((*kd << 1) - 1 < nr) {
  682. /* Dependent on the the number of diagonals either */
  683. /* CLARTV or CROT is used */
  684. i__3 = *kd - 1;
  685. for (l = 1; l <= i__3; ++l) {
  686. if (j2 + l > *n) {
  687. nrt = nr - 1;
  688. } else {
  689. nrt = nr;
  690. }
  691. if (nrt > 0) {
  692. clartv_(&nrt, &ab[*kd - l + (j1 + l) *
  693. ab_dim1], &inca, &ab[*kd - l + 1
  694. + (j1 + l) * ab_dim1], &inca, &
  695. d__[j1], &work[j1], &kd1);
  696. }
  697. /* L30: */
  698. }
  699. } else {
  700. j1end = j1 + kd1 * (nr - 2);
  701. if (j1end >= j1) {
  702. i__3 = j1end;
  703. i__2 = kd1;
  704. for (jin = j1; i__2 < 0 ? jin >= i__3 : jin <=
  705. i__3; jin += i__2) {
  706. i__4 = *kd - 1;
  707. crot_(&i__4, &ab[*kd - 1 + (jin + 1) *
  708. ab_dim1], &incx, &ab[*kd + (jin +
  709. 1) * ab_dim1], &incx, &d__[jin], &
  710. work[jin]);
  711. /* L40: */
  712. }
  713. }
  714. /* Computing MIN */
  715. i__2 = kdm1, i__3 = *n - j2;
  716. lend = f2cmin(i__2,i__3);
  717. last = j1end + kd1;
  718. if (lend > 0) {
  719. crot_(&lend, &ab[*kd - 1 + (last + 1) *
  720. ab_dim1], &incx, &ab[*kd + (last + 1)
  721. * ab_dim1], &incx, &d__[last], &work[
  722. last]);
  723. }
  724. }
  725. }
  726. if (wantq) {
  727. /* accumulate product of plane rotations in Q */
  728. if (initq) {
  729. /* take advantage of the fact that Q was */
  730. /* initially the Identity matrix */
  731. iqend = f2cmax(iqend,j2);
  732. /* Computing MAX */
  733. i__2 = 0, i__3 = k - 3;
  734. i2 = f2cmax(i__2,i__3);
  735. iqaend = i__ * *kd + 1;
  736. if (k == 2) {
  737. iqaend += *kd;
  738. }
  739. iqaend = f2cmin(iqaend,iqend);
  740. i__2 = j2;
  741. i__3 = kd1;
  742. for (j = j1; i__3 < 0 ? j >= i__2 : j <= i__2; j
  743. += i__3) {
  744. ibl = i__ - i2 / kdm1;
  745. ++i2;
  746. /* Computing MAX */
  747. i__4 = 1, i__5 = j - ibl;
  748. iqb = f2cmax(i__4,i__5);
  749. nq = iqaend + 1 - iqb;
  750. /* Computing MIN */
  751. i__4 = iqaend + *kd;
  752. iqaend = f2cmin(i__4,iqend);
  753. r_cnjg(&q__1, &work[j]);
  754. crot_(&nq, &q[iqb + (j - 1) * q_dim1], &c__1,
  755. &q[iqb + j * q_dim1], &c__1, &d__[j],
  756. &q__1);
  757. /* L50: */
  758. }
  759. } else {
  760. i__3 = j2;
  761. i__2 = kd1;
  762. for (j = j1; i__2 < 0 ? j >= i__3 : j <= i__3; j
  763. += i__2) {
  764. r_cnjg(&q__1, &work[j]);
  765. crot_(n, &q[(j - 1) * q_dim1 + 1], &c__1, &q[
  766. j * q_dim1 + 1], &c__1, &d__[j], &
  767. q__1);
  768. /* L60: */
  769. }
  770. }
  771. }
  772. if (j2 + kdn > *n) {
  773. /* adjust J2 to keep within the bounds of the matrix */
  774. --nr;
  775. j2 = j2 - kdn - 1;
  776. }
  777. i__2 = j2;
  778. i__3 = kd1;
  779. for (j = j1; i__3 < 0 ? j >= i__2 : j <= i__2; j += i__3)
  780. {
  781. /* create nonzero element a(j-1,j+kd) outside the band */
  782. /* and store it in WORK */
  783. i__4 = j + *kd;
  784. i__5 = j;
  785. i__6 = (j + *kd) * ab_dim1 + 1;
  786. q__1.r = work[i__5].r * ab[i__6].r - work[i__5].i *
  787. ab[i__6].i, q__1.i = work[i__5].r * ab[i__6]
  788. .i + work[i__5].i * ab[i__6].r;
  789. work[i__4].r = q__1.r, work[i__4].i = q__1.i;
  790. i__4 = (j + *kd) * ab_dim1 + 1;
  791. i__5 = j;
  792. i__6 = (j + *kd) * ab_dim1 + 1;
  793. q__1.r = d__[i__5] * ab[i__6].r, q__1.i = d__[i__5] *
  794. ab[i__6].i;
  795. ab[i__4].r = q__1.r, ab[i__4].i = q__1.i;
  796. /* L70: */
  797. }
  798. /* L80: */
  799. }
  800. /* L90: */
  801. }
  802. }
  803. if (*kd > 0) {
  804. /* make off-diagonal elements real and copy them to E */
  805. i__1 = *n - 1;
  806. for (i__ = 1; i__ <= i__1; ++i__) {
  807. i__3 = *kd + (i__ + 1) * ab_dim1;
  808. t.r = ab[i__3].r, t.i = ab[i__3].i;
  809. abst = c_abs(&t);
  810. i__3 = *kd + (i__ + 1) * ab_dim1;
  811. ab[i__3].r = abst, ab[i__3].i = 0.f;
  812. e[i__] = abst;
  813. if (abst != 0.f) {
  814. q__1.r = t.r / abst, q__1.i = t.i / abst;
  815. t.r = q__1.r, t.i = q__1.i;
  816. } else {
  817. t.r = 1.f, t.i = 0.f;
  818. }
  819. if (i__ < *n - 1) {
  820. i__3 = *kd + (i__ + 2) * ab_dim1;
  821. i__2 = *kd + (i__ + 2) * ab_dim1;
  822. q__1.r = ab[i__2].r * t.r - ab[i__2].i * t.i, q__1.i = ab[
  823. i__2].r * t.i + ab[i__2].i * t.r;
  824. ab[i__3].r = q__1.r, ab[i__3].i = q__1.i;
  825. }
  826. if (wantq) {
  827. r_cnjg(&q__1, &t);
  828. cscal_(n, &q__1, &q[(i__ + 1) * q_dim1 + 1], &c__1);
  829. }
  830. /* L100: */
  831. }
  832. } else {
  833. /* set E to zero if original matrix was diagonal */
  834. i__1 = *n - 1;
  835. for (i__ = 1; i__ <= i__1; ++i__) {
  836. e[i__] = 0.f;
  837. /* L110: */
  838. }
  839. }
  840. /* copy diagonal elements to D */
  841. i__1 = *n;
  842. for (i__ = 1; i__ <= i__1; ++i__) {
  843. i__3 = i__;
  844. i__2 = kd1 + i__ * ab_dim1;
  845. d__[i__3] = ab[i__2].r;
  846. /* L120: */
  847. }
  848. } else {
  849. if (*kd > 1) {
  850. /* Reduce to complex Hermitian tridiagonal form, working with */
  851. /* the lower triangle */
  852. nr = 0;
  853. j1 = kdn + 2;
  854. j2 = 1;
  855. i__1 = ab_dim1 + 1;
  856. i__3 = ab_dim1 + 1;
  857. r__1 = ab[i__3].r;
  858. ab[i__1].r = r__1, ab[i__1].i = 0.f;
  859. i__1 = *n - 2;
  860. for (i__ = 1; i__ <= i__1; ++i__) {
  861. /* Reduce i-th column of matrix to tridiagonal form */
  862. for (k = kdn + 1; k >= 2; --k) {
  863. j1 += kdn;
  864. j2 += kdn;
  865. if (nr > 0) {
  866. /* generate plane rotations to annihilate nonzero */
  867. /* elements which have been created outside the band */
  868. clargv_(&nr, &ab[kd1 + (j1 - kd1) * ab_dim1], &inca, &
  869. work[j1], &kd1, &d__[j1], &kd1);
  870. /* apply plane rotations from one side */
  871. /* Dependent on the the number of diagonals either */
  872. /* CLARTV or CROT is used */
  873. if (nr > (*kd << 1) - 1) {
  874. i__3 = *kd - 1;
  875. for (l = 1; l <= i__3; ++l) {
  876. clartv_(&nr, &ab[kd1 - l + (j1 - kd1 + l) *
  877. ab_dim1], &inca, &ab[kd1 - l + 1 + (
  878. j1 - kd1 + l) * ab_dim1], &inca, &d__[
  879. j1], &work[j1], &kd1);
  880. /* L130: */
  881. }
  882. } else {
  883. jend = j1 + kd1 * (nr - 1);
  884. i__3 = jend;
  885. i__2 = kd1;
  886. for (jinc = j1; i__2 < 0 ? jinc >= i__3 : jinc <=
  887. i__3; jinc += i__2) {
  888. crot_(&kdm1, &ab[*kd + (jinc - *kd) * ab_dim1]
  889. , &incx, &ab[kd1 + (jinc - *kd) *
  890. ab_dim1], &incx, &d__[jinc], &work[
  891. jinc]);
  892. /* L140: */
  893. }
  894. }
  895. }
  896. if (k > 2) {
  897. if (k <= *n - i__ + 1) {
  898. /* generate plane rotation to annihilate a(i+k-1,i) */
  899. /* within the band */
  900. clartg_(&ab[k - 1 + i__ * ab_dim1], &ab[k + i__ *
  901. ab_dim1], &d__[i__ + k - 1], &work[i__ +
  902. k - 1], &temp);
  903. i__2 = k - 1 + i__ * ab_dim1;
  904. ab[i__2].r = temp.r, ab[i__2].i = temp.i;
  905. /* apply rotation from the left */
  906. i__2 = k - 3;
  907. i__3 = *ldab - 1;
  908. i__4 = *ldab - 1;
  909. crot_(&i__2, &ab[k - 2 + (i__ + 1) * ab_dim1], &
  910. i__3, &ab[k - 1 + (i__ + 1) * ab_dim1], &
  911. i__4, &d__[i__ + k - 1], &work[i__ + k -
  912. 1]);
  913. }
  914. ++nr;
  915. j1 = j1 - kdn - 1;
  916. }
  917. /* apply plane rotations from both sides to diagonal */
  918. /* blocks */
  919. if (nr > 0) {
  920. clar2v_(&nr, &ab[(j1 - 1) * ab_dim1 + 1], &ab[j1 *
  921. ab_dim1 + 1], &ab[(j1 - 1) * ab_dim1 + 2], &
  922. inca, &d__[j1], &work[j1], &kd1);
  923. }
  924. /* apply plane rotations from the right */
  925. /* Dependent on the the number of diagonals either */
  926. /* CLARTV or CROT is used */
  927. if (nr > 0) {
  928. clacgv_(&nr, &work[j1], &kd1);
  929. if (nr > (*kd << 1) - 1) {
  930. i__2 = *kd - 1;
  931. for (l = 1; l <= i__2; ++l) {
  932. if (j2 + l > *n) {
  933. nrt = nr - 1;
  934. } else {
  935. nrt = nr;
  936. }
  937. if (nrt > 0) {
  938. clartv_(&nrt, &ab[l + 2 + (j1 - 1) *
  939. ab_dim1], &inca, &ab[l + 1 + j1 *
  940. ab_dim1], &inca, &d__[j1], &work[
  941. j1], &kd1);
  942. }
  943. /* L150: */
  944. }
  945. } else {
  946. j1end = j1 + kd1 * (nr - 2);
  947. if (j1end >= j1) {
  948. i__2 = j1end;
  949. i__3 = kd1;
  950. for (j1inc = j1; i__3 < 0 ? j1inc >= i__2 :
  951. j1inc <= i__2; j1inc += i__3) {
  952. crot_(&kdm1, &ab[(j1inc - 1) * ab_dim1 +
  953. 3], &c__1, &ab[j1inc * ab_dim1 +
  954. 2], &c__1, &d__[j1inc], &work[
  955. j1inc]);
  956. /* L160: */
  957. }
  958. }
  959. /* Computing MIN */
  960. i__3 = kdm1, i__2 = *n - j2;
  961. lend = f2cmin(i__3,i__2);
  962. last = j1end + kd1;
  963. if (lend > 0) {
  964. crot_(&lend, &ab[(last - 1) * ab_dim1 + 3], &
  965. c__1, &ab[last * ab_dim1 + 2], &c__1,
  966. &d__[last], &work[last]);
  967. }
  968. }
  969. }
  970. if (wantq) {
  971. /* accumulate product of plane rotations in Q */
  972. if (initq) {
  973. /* take advantage of the fact that Q was */
  974. /* initially the Identity matrix */
  975. iqend = f2cmax(iqend,j2);
  976. /* Computing MAX */
  977. i__3 = 0, i__2 = k - 3;
  978. i2 = f2cmax(i__3,i__2);
  979. iqaend = i__ * *kd + 1;
  980. if (k == 2) {
  981. iqaend += *kd;
  982. }
  983. iqaend = f2cmin(iqaend,iqend);
  984. i__3 = j2;
  985. i__2 = kd1;
  986. for (j = j1; i__2 < 0 ? j >= i__3 : j <= i__3; j
  987. += i__2) {
  988. ibl = i__ - i2 / kdm1;
  989. ++i2;
  990. /* Computing MAX */
  991. i__4 = 1, i__5 = j - ibl;
  992. iqb = f2cmax(i__4,i__5);
  993. nq = iqaend + 1 - iqb;
  994. /* Computing MIN */
  995. i__4 = iqaend + *kd;
  996. iqaend = f2cmin(i__4,iqend);
  997. crot_(&nq, &q[iqb + (j - 1) * q_dim1], &c__1,
  998. &q[iqb + j * q_dim1], &c__1, &d__[j],
  999. &work[j]);
  1000. /* L170: */
  1001. }
  1002. } else {
  1003. i__2 = j2;
  1004. i__3 = kd1;
  1005. for (j = j1; i__3 < 0 ? j >= i__2 : j <= i__2; j
  1006. += i__3) {
  1007. crot_(n, &q[(j - 1) * q_dim1 + 1], &c__1, &q[
  1008. j * q_dim1 + 1], &c__1, &d__[j], &
  1009. work[j]);
  1010. /* L180: */
  1011. }
  1012. }
  1013. }
  1014. if (j2 + kdn > *n) {
  1015. /* adjust J2 to keep within the bounds of the matrix */
  1016. --nr;
  1017. j2 = j2 - kdn - 1;
  1018. }
  1019. i__3 = j2;
  1020. i__2 = kd1;
  1021. for (j = j1; i__2 < 0 ? j >= i__3 : j <= i__3; j += i__2)
  1022. {
  1023. /* create nonzero element a(j+kd,j-1) outside the */
  1024. /* band and store it in WORK */
  1025. i__4 = j + *kd;
  1026. i__5 = j;
  1027. i__6 = kd1 + j * ab_dim1;
  1028. q__1.r = work[i__5].r * ab[i__6].r - work[i__5].i *
  1029. ab[i__6].i, q__1.i = work[i__5].r * ab[i__6]
  1030. .i + work[i__5].i * ab[i__6].r;
  1031. work[i__4].r = q__1.r, work[i__4].i = q__1.i;
  1032. i__4 = kd1 + j * ab_dim1;
  1033. i__5 = j;
  1034. i__6 = kd1 + j * ab_dim1;
  1035. q__1.r = d__[i__5] * ab[i__6].r, q__1.i = d__[i__5] *
  1036. ab[i__6].i;
  1037. ab[i__4].r = q__1.r, ab[i__4].i = q__1.i;
  1038. /* L190: */
  1039. }
  1040. /* L200: */
  1041. }
  1042. /* L210: */
  1043. }
  1044. }
  1045. if (*kd > 0) {
  1046. /* make off-diagonal elements real and copy them to E */
  1047. i__1 = *n - 1;
  1048. for (i__ = 1; i__ <= i__1; ++i__) {
  1049. i__2 = i__ * ab_dim1 + 2;
  1050. t.r = ab[i__2].r, t.i = ab[i__2].i;
  1051. abst = c_abs(&t);
  1052. i__2 = i__ * ab_dim1 + 2;
  1053. ab[i__2].r = abst, ab[i__2].i = 0.f;
  1054. e[i__] = abst;
  1055. if (abst != 0.f) {
  1056. q__1.r = t.r / abst, q__1.i = t.i / abst;
  1057. t.r = q__1.r, t.i = q__1.i;
  1058. } else {
  1059. t.r = 1.f, t.i = 0.f;
  1060. }
  1061. if (i__ < *n - 1) {
  1062. i__2 = (i__ + 1) * ab_dim1 + 2;
  1063. i__3 = (i__ + 1) * ab_dim1 + 2;
  1064. q__1.r = ab[i__3].r * t.r - ab[i__3].i * t.i, q__1.i = ab[
  1065. i__3].r * t.i + ab[i__3].i * t.r;
  1066. ab[i__2].r = q__1.r, ab[i__2].i = q__1.i;
  1067. }
  1068. if (wantq) {
  1069. cscal_(n, &t, &q[(i__ + 1) * q_dim1 + 1], &c__1);
  1070. }
  1071. /* L220: */
  1072. }
  1073. } else {
  1074. /* set E to zero if original matrix was diagonal */
  1075. i__1 = *n - 1;
  1076. for (i__ = 1; i__ <= i__1; ++i__) {
  1077. e[i__] = 0.f;
  1078. /* L230: */
  1079. }
  1080. }
  1081. /* copy diagonal elements to D */
  1082. i__1 = *n;
  1083. for (i__ = 1; i__ <= i__1; ++i__) {
  1084. i__2 = i__;
  1085. i__3 = i__ * ab_dim1 + 1;
  1086. d__[i__2] = ab[i__3].r;
  1087. /* L240: */
  1088. }
  1089. }
  1090. return 0;
  1091. /* End of CHBTRD */
  1092. } /* chbtrd_ */