You can not select more than 25 topics Topics must start with a chinese character,a letter or number, can include dashes ('-') and can be up to 35 characters long.

cgeqpf.c 18 kB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632
  1. #include <math.h>
  2. #include <stdlib.h>
  3. #include <string.h>
  4. #include <stdio.h>
  5. #include <complex.h>
  6. #ifdef complex
  7. #undef complex
  8. #endif
  9. #ifdef I
  10. #undef I
  11. #endif
  12. #if defined(_WIN64)
  13. typedef long long BLASLONG;
  14. typedef unsigned long long BLASULONG;
  15. #else
  16. typedef long BLASLONG;
  17. typedef unsigned long BLASULONG;
  18. #endif
  19. #ifdef LAPACK_ILP64
  20. typedef BLASLONG blasint;
  21. #if defined(_WIN64)
  22. #define blasabs(x) llabs(x)
  23. #else
  24. #define blasabs(x) labs(x)
  25. #endif
  26. #else
  27. typedef int blasint;
  28. #define blasabs(x) abs(x)
  29. #endif
  30. typedef blasint integer;
  31. typedef unsigned int uinteger;
  32. typedef char *address;
  33. typedef short int shortint;
  34. typedef float real;
  35. typedef double doublereal;
  36. typedef struct { real r, i; } complex;
  37. typedef struct { doublereal r, i; } doublecomplex;
  38. #ifdef _MSC_VER
  39. static inline _Fcomplex Cf(complex *z) {_Fcomplex zz={z->r , z->i}; return zz;}
  40. static inline _Dcomplex Cd(doublecomplex *z) {_Dcomplex zz={z->r , z->i};return zz;}
  41. static inline _Fcomplex * _pCf(complex *z) {return (_Fcomplex*)z;}
  42. static inline _Dcomplex * _pCd(doublecomplex *z) {return (_Dcomplex*)z;}
  43. #else
  44. static inline _Complex float Cf(complex *z) {return z->r + z->i*_Complex_I;}
  45. static inline _Complex double Cd(doublecomplex *z) {return z->r + z->i*_Complex_I;}
  46. static inline _Complex float * _pCf(complex *z) {return (_Complex float*)z;}
  47. static inline _Complex double * _pCd(doublecomplex *z) {return (_Complex double*)z;}
  48. #endif
  49. #define pCf(z) (*_pCf(z))
  50. #define pCd(z) (*_pCd(z))
  51. typedef int logical;
  52. typedef short int shortlogical;
  53. typedef char logical1;
  54. typedef char integer1;
  55. #define TRUE_ (1)
  56. #define FALSE_ (0)
  57. /* Extern is for use with -E */
  58. #ifndef Extern
  59. #define Extern extern
  60. #endif
  61. /* I/O stuff */
  62. typedef int flag;
  63. typedef int ftnlen;
  64. typedef int ftnint;
  65. /*external read, write*/
  66. typedef struct
  67. { flag cierr;
  68. ftnint ciunit;
  69. flag ciend;
  70. char *cifmt;
  71. ftnint cirec;
  72. } cilist;
  73. /*internal read, write*/
  74. typedef struct
  75. { flag icierr;
  76. char *iciunit;
  77. flag iciend;
  78. char *icifmt;
  79. ftnint icirlen;
  80. ftnint icirnum;
  81. } icilist;
  82. /*open*/
  83. typedef struct
  84. { flag oerr;
  85. ftnint ounit;
  86. char *ofnm;
  87. ftnlen ofnmlen;
  88. char *osta;
  89. char *oacc;
  90. char *ofm;
  91. ftnint orl;
  92. char *oblnk;
  93. } olist;
  94. /*close*/
  95. typedef struct
  96. { flag cerr;
  97. ftnint cunit;
  98. char *csta;
  99. } cllist;
  100. /*rewind, backspace, endfile*/
  101. typedef struct
  102. { flag aerr;
  103. ftnint aunit;
  104. } alist;
  105. /* inquire */
  106. typedef struct
  107. { flag inerr;
  108. ftnint inunit;
  109. char *infile;
  110. ftnlen infilen;
  111. ftnint *inex; /*parameters in standard's order*/
  112. ftnint *inopen;
  113. ftnint *innum;
  114. ftnint *innamed;
  115. char *inname;
  116. ftnlen innamlen;
  117. char *inacc;
  118. ftnlen inacclen;
  119. char *inseq;
  120. ftnlen inseqlen;
  121. char *indir;
  122. ftnlen indirlen;
  123. char *infmt;
  124. ftnlen infmtlen;
  125. char *inform;
  126. ftnint informlen;
  127. char *inunf;
  128. ftnlen inunflen;
  129. ftnint *inrecl;
  130. ftnint *innrec;
  131. char *inblank;
  132. ftnlen inblanklen;
  133. } inlist;
  134. #define VOID void
  135. union Multitype { /* for multiple entry points */
  136. integer1 g;
  137. shortint h;
  138. integer i;
  139. /* longint j; */
  140. real r;
  141. doublereal d;
  142. complex c;
  143. doublecomplex z;
  144. };
  145. typedef union Multitype Multitype;
  146. struct Vardesc { /* for Namelist */
  147. char *name;
  148. char *addr;
  149. ftnlen *dims;
  150. int type;
  151. };
  152. typedef struct Vardesc Vardesc;
  153. struct Namelist {
  154. char *name;
  155. Vardesc **vars;
  156. int nvars;
  157. };
  158. typedef struct Namelist Namelist;
  159. #define abs(x) ((x) >= 0 ? (x) : -(x))
  160. #define dabs(x) (fabs(x))
  161. #define f2cmin(a,b) ((a) <= (b) ? (a) : (b))
  162. #define f2cmax(a,b) ((a) >= (b) ? (a) : (b))
  163. #define dmin(a,b) (f2cmin(a,b))
  164. #define dmax(a,b) (f2cmax(a,b))
  165. #define bit_test(a,b) ((a) >> (b) & 1)
  166. #define bit_clear(a,b) ((a) & ~((uinteger)1 << (b)))
  167. #define bit_set(a,b) ((a) | ((uinteger)1 << (b)))
  168. #define abort_() { sig_die("Fortran abort routine called", 1); }
  169. #define c_abs(z) (cabsf(Cf(z)))
  170. #define c_cos(R,Z) { pCf(R)=ccos(Cf(Z)); }
  171. #ifdef _MSC_VER
  172. #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]);}
  173. #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]);}
  174. #else
  175. #define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
  176. #define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
  177. #endif
  178. #define c_exp(R, Z) {pCf(R) = cexpf(Cf(Z));}
  179. #define c_log(R, Z) {pCf(R) = clogf(Cf(Z));}
  180. #define c_sin(R, Z) {pCf(R) = csinf(Cf(Z));}
  181. //#define c_sqrt(R, Z) {*(R) = csqrtf(Cf(Z));}
  182. #define c_sqrt(R, Z) {pCf(R) = csqrtf(Cf(Z));}
  183. #define d_abs(x) (fabs(*(x)))
  184. #define d_acos(x) (acos(*(x)))
  185. #define d_asin(x) (asin(*(x)))
  186. #define d_atan(x) (atan(*(x)))
  187. #define d_atn2(x, y) (atan2(*(x),*(y)))
  188. #define d_cnjg(R, Z) { pCd(R) = conj(Cd(Z)); }
  189. #define r_cnjg(R, Z) { pCf(R) = conjf(Cf(Z)); }
  190. #define d_cos(x) (cos(*(x)))
  191. #define d_cosh(x) (cosh(*(x)))
  192. #define d_dim(__a, __b) ( *(__a) > *(__b) ? *(__a) - *(__b) : 0.0 )
  193. #define d_exp(x) (exp(*(x)))
  194. #define d_imag(z) (cimag(Cd(z)))
  195. #define r_imag(z) (cimagf(Cf(z)))
  196. #define d_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
  197. #define r_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
  198. #define d_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
  199. #define r_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
  200. #define d_log(x) (log(*(x)))
  201. #define d_mod(x, y) (fmod(*(x), *(y)))
  202. #define u_nint(__x) ((__x)>=0 ? floor((__x) + .5) : -floor(.5 - (__x)))
  203. #define d_nint(x) u_nint(*(x))
  204. #define u_sign(__a,__b) ((__b) >= 0 ? ((__a) >= 0 ? (__a) : -(__a)) : -((__a) >= 0 ? (__a) : -(__a)))
  205. #define d_sign(a,b) u_sign(*(a),*(b))
  206. #define r_sign(a,b) u_sign(*(a),*(b))
  207. #define d_sin(x) (sin(*(x)))
  208. #define d_sinh(x) (sinh(*(x)))
  209. #define d_sqrt(x) (sqrt(*(x)))
  210. #define d_tan(x) (tan(*(x)))
  211. #define d_tanh(x) (tanh(*(x)))
  212. #define i_abs(x) abs(*(x))
  213. #define i_dnnt(x) ((integer)u_nint(*(x)))
  214. #define i_len(s, n) (n)
  215. #define i_nint(x) ((integer)u_nint(*(x)))
  216. #define i_sign(a,b) ((integer)u_sign((integer)*(a),(integer)*(b)))
  217. #define pow_dd(ap, bp) ( pow(*(ap), *(bp)))
  218. #define pow_si(B,E) spow_ui(*(B),*(E))
  219. #define pow_ri(B,E) spow_ui(*(B),*(E))
  220. #define pow_di(B,E) dpow_ui(*(B),*(E))
  221. #define pow_zi(p, a, b) {pCd(p) = zpow_ui(Cd(a), *(b));}
  222. #define pow_ci(p, a, b) {pCf(p) = cpow_ui(Cf(a), *(b));}
  223. #define pow_zz(R,A,B) {pCd(R) = cpow(Cd(A),*(B));}
  224. #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++ = ' '; }
  225. #define s_cmp(a,b,c,d) ((integer)strncmp((a),(b),f2cmin((c),(d))))
  226. #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]; }
  227. #define sig_die(s, kill) { exit(1); }
  228. #define s_stop(s, n) {exit(0);}
  229. #define z_abs(z) (cabs(Cd(z)))
  230. #define z_exp(R, Z) {pCd(R) = cexp(Cd(Z));}
  231. #define z_sqrt(R, Z) {pCd(R) = csqrt(Cd(Z));}
  232. #define myexit_() break;
  233. #define mycycle() continue;
  234. #define myceiling(w) {ceil(w)}
  235. #define myhuge(w) {HUGE_VAL}
  236. //#define mymaxloc_(w,s,e,n) {if (sizeof(*(w)) == sizeof(double)) dmaxloc_((w),*(s),*(e),n); else dmaxloc_((w),*(s),*(e),n);}
  237. #define mymaxloc(w,s,e,n) {dmaxloc_(w,*(s),*(e),n)}
  238. /* procedure parameter types for -A and -C++ */
  239. #define F2C_proc_par_types 1
  240. /* -- translated by f2c (version 20000121).
  241. You must link the resulting object file with the libraries:
  242. -lf2c -lm (in that order)
  243. */
  244. /* Table of constant values */
  245. static integer c__1 = 1;
  246. /* > \brief \b CGEQPF */
  247. /* =========== DOCUMENTATION =========== */
  248. /* Online html documentation available at */
  249. /* http://www.netlib.org/lapack/explore-html/ */
  250. /* > \htmlonly */
  251. /* > Download CGEQPF + dependencies */
  252. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/cgeqpf.
  253. f"> */
  254. /* > [TGZ]</a> */
  255. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/cgeqpf.
  256. f"> */
  257. /* > [ZIP]</a> */
  258. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/cgeqpf.
  259. f"> */
  260. /* > [TXT]</a> */
  261. /* > \endhtmlonly */
  262. /* Definition: */
  263. /* =========== */
  264. /* SUBROUTINE CGEQPF( M, N, A, LDA, JPVT, TAU, WORK, RWORK, INFO ) */
  265. /* INTEGER INFO, LDA, M, N */
  266. /* INTEGER JPVT( * ) */
  267. /* REAL RWORK( * ) */
  268. /* COMPLEX A( LDA, * ), TAU( * ), WORK( * ) */
  269. /* > \par Purpose: */
  270. /* ============= */
  271. /* > */
  272. /* > \verbatim */
  273. /* > */
  274. /* > This routine is deprecated and has been replaced by routine CGEQP3. */
  275. /* > */
  276. /* > CGEQPF computes a QR factorization with column pivoting of a */
  277. /* > complex M-by-N matrix A: A*P = Q*R. */
  278. /* > \endverbatim */
  279. /* Arguments: */
  280. /* ========== */
  281. /* > \param[in] M */
  282. /* > \verbatim */
  283. /* > M is INTEGER */
  284. /* > The number of rows of the matrix A. M >= 0. */
  285. /* > \endverbatim */
  286. /* > */
  287. /* > \param[in] N */
  288. /* > \verbatim */
  289. /* > N is INTEGER */
  290. /* > The number of columns of the matrix A. N >= 0 */
  291. /* > \endverbatim */
  292. /* > */
  293. /* > \param[in,out] A */
  294. /* > \verbatim */
  295. /* > A is COMPLEX array, dimension (LDA,N) */
  296. /* > On entry, the M-by-N matrix A. */
  297. /* > On exit, the upper triangle of the array contains the */
  298. /* > f2cmin(M,N)-by-N upper triangular matrix R; the elements */
  299. /* > below the diagonal, together with the array TAU, */
  300. /* > represent the unitary matrix Q as a product of */
  301. /* > f2cmin(m,n) elementary reflectors. */
  302. /* > \endverbatim */
  303. /* > */
  304. /* > \param[in] LDA */
  305. /* > \verbatim */
  306. /* > LDA is INTEGER */
  307. /* > The leading dimension of the array A. LDA >= f2cmax(1,M). */
  308. /* > \endverbatim */
  309. /* > */
  310. /* > \param[in,out] JPVT */
  311. /* > \verbatim */
  312. /* > JPVT is INTEGER array, dimension (N) */
  313. /* > On entry, if JPVT(i) .ne. 0, the i-th column of A is permuted */
  314. /* > to the front of A*P (a leading column); if JPVT(i) = 0, */
  315. /* > the i-th column of A is a free column. */
  316. /* > On exit, if JPVT(i) = k, then the i-th column of A*P */
  317. /* > was the k-th column of A. */
  318. /* > \endverbatim */
  319. /* > */
  320. /* > \param[out] TAU */
  321. /* > \verbatim */
  322. /* > TAU is COMPLEX array, dimension (f2cmin(M,N)) */
  323. /* > The scalar factors of the elementary reflectors. */
  324. /* > \endverbatim */
  325. /* > */
  326. /* > \param[out] WORK */
  327. /* > \verbatim */
  328. /* > WORK is COMPLEX array, dimension (N) */
  329. /* > \endverbatim */
  330. /* > */
  331. /* > \param[out] RWORK */
  332. /* > \verbatim */
  333. /* > RWORK is REAL array, dimension (2*N) */
  334. /* > \endverbatim */
  335. /* > */
  336. /* > \param[out] INFO */
  337. /* > \verbatim */
  338. /* > INFO is INTEGER */
  339. /* > = 0: successful exit */
  340. /* > < 0: if INFO = -i, the i-th argument had an illegal value */
  341. /* > \endverbatim */
  342. /* Authors: */
  343. /* ======== */
  344. /* > \author Univ. of Tennessee */
  345. /* > \author Univ. of California Berkeley */
  346. /* > \author Univ. of Colorado Denver */
  347. /* > \author NAG Ltd. */
  348. /* > \date December 2016 */
  349. /* > \ingroup complexGEcomputational */
  350. /* > \par Further Details: */
  351. /* ===================== */
  352. /* > */
  353. /* > \verbatim */
  354. /* > */
  355. /* > The matrix Q is represented as a product of elementary reflectors */
  356. /* > */
  357. /* > Q = H(1) H(2) . . . H(n) */
  358. /* > */
  359. /* > Each H(i) has the form */
  360. /* > */
  361. /* > H = I - tau * v * v**H */
  362. /* > */
  363. /* > where tau is a complex scalar, and v is a complex vector with */
  364. /* > v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i). */
  365. /* > */
  366. /* > The matrix P is represented in jpvt as follows: If */
  367. /* > jpvt(j) = i */
  368. /* > then the jth column of P is the ith canonical unit vector. */
  369. /* > */
  370. /* > Partial column norm updating strategy modified by */
  371. /* > Z. Drmac and Z. Bujanovic, Dept. of Mathematics, */
  372. /* > University of Zagreb, Croatia. */
  373. /* > -- April 2011 -- */
  374. /* > For more details see LAPACK Working Note 176. */
  375. /* > \endverbatim */
  376. /* > */
  377. /* ===================================================================== */
  378. /* Subroutine */ void cgeqpf_(integer *m, integer *n, complex *a, integer *lda,
  379. integer *jpvt, complex *tau, complex *work, real *rwork, integer *
  380. info)
  381. {
  382. /* System generated locals */
  383. integer a_dim1, a_offset, i__1, i__2, i__3;
  384. real r__1, r__2;
  385. complex q__1;
  386. /* Local variables */
  387. real temp, temp2;
  388. integer i__, j;
  389. real tol3z;
  390. extern /* Subroutine */ void clarf_(char *, integer *, integer *, complex *
  391. , integer *, complex *, complex *, integer *, complex *),
  392. cswap_(integer *, complex *, integer *, complex *, integer *);
  393. integer itemp;
  394. extern /* Subroutine */ void cgeqr2_(integer *, integer *, complex *,
  395. integer *, complex *, complex *, integer *);
  396. extern real scnrm2_(integer *, complex *, integer *);
  397. extern /* Subroutine */ void cunm2r_(char *, char *, integer *, integer *,
  398. integer *, complex *, integer *, complex *, complex *, integer *,
  399. complex *, integer *);
  400. integer ma, mn;
  401. extern /* Subroutine */ void clarfg_(integer *, complex *, complex *,
  402. integer *, complex *);
  403. extern real slamch_(char *);
  404. extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
  405. extern integer isamax_(integer *, real *, integer *);
  406. complex aii;
  407. integer pvt;
  408. /* -- LAPACK computational routine (version 3.7.0) -- */
  409. /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
  410. /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
  411. /* December 2016 */
  412. /* ===================================================================== */
  413. /* Test the input arguments */
  414. /* Parameter adjustments */
  415. a_dim1 = *lda;
  416. a_offset = 1 + a_dim1 * 1;
  417. a -= a_offset;
  418. --jpvt;
  419. --tau;
  420. --work;
  421. --rwork;
  422. /* Function Body */
  423. *info = 0;
  424. if (*m < 0) {
  425. *info = -1;
  426. } else if (*n < 0) {
  427. *info = -2;
  428. } else if (*lda < f2cmax(1,*m)) {
  429. *info = -4;
  430. }
  431. if (*info != 0) {
  432. i__1 = -(*info);
  433. xerbla_("CGEQPF", &i__1, 6);
  434. return;
  435. }
  436. mn = f2cmin(*m,*n);
  437. tol3z = sqrt(slamch_("Epsilon"));
  438. /* Move initial columns up front */
  439. itemp = 1;
  440. i__1 = *n;
  441. for (i__ = 1; i__ <= i__1; ++i__) {
  442. if (jpvt[i__] != 0) {
  443. if (i__ != itemp) {
  444. cswap_(m, &a[i__ * a_dim1 + 1], &c__1, &a[itemp * a_dim1 + 1],
  445. &c__1);
  446. jpvt[i__] = jpvt[itemp];
  447. jpvt[itemp] = i__;
  448. } else {
  449. jpvt[i__] = i__;
  450. }
  451. ++itemp;
  452. } else {
  453. jpvt[i__] = i__;
  454. }
  455. /* L10: */
  456. }
  457. --itemp;
  458. /* Compute the QR factorization and update remaining columns */
  459. if (itemp > 0) {
  460. ma = f2cmin(itemp,*m);
  461. cgeqr2_(m, &ma, &a[a_offset], lda, &tau[1], &work[1], info);
  462. if (ma < *n) {
  463. i__1 = *n - ma;
  464. cunm2r_("Left", "Conjugate transpose", m, &i__1, &ma, &a[a_offset]
  465. , lda, &tau[1], &a[(ma + 1) * a_dim1 + 1], lda, &work[1],
  466. info);
  467. }
  468. }
  469. if (itemp < mn) {
  470. /* Initialize partial column norms. The first n elements of */
  471. /* work store the exact column norms. */
  472. i__1 = *n;
  473. for (i__ = itemp + 1; i__ <= i__1; ++i__) {
  474. i__2 = *m - itemp;
  475. rwork[i__] = scnrm2_(&i__2, &a[itemp + 1 + i__ * a_dim1], &c__1);
  476. rwork[*n + i__] = rwork[i__];
  477. /* L20: */
  478. }
  479. /* Compute factorization */
  480. i__1 = mn;
  481. for (i__ = itemp + 1; i__ <= i__1; ++i__) {
  482. /* Determine ith pivot column and swap if necessary */
  483. i__2 = *n - i__ + 1;
  484. pvt = i__ - 1 + isamax_(&i__2, &rwork[i__], &c__1);
  485. if (pvt != i__) {
  486. cswap_(m, &a[pvt * a_dim1 + 1], &c__1, &a[i__ * a_dim1 + 1], &
  487. c__1);
  488. itemp = jpvt[pvt];
  489. jpvt[pvt] = jpvt[i__];
  490. jpvt[i__] = itemp;
  491. rwork[pvt] = rwork[i__];
  492. rwork[*n + pvt] = rwork[*n + i__];
  493. }
  494. /* Generate elementary reflector H(i) */
  495. i__2 = i__ + i__ * a_dim1;
  496. aii.r = a[i__2].r, aii.i = a[i__2].i;
  497. i__2 = *m - i__ + 1;
  498. /* Computing MIN */
  499. i__3 = i__ + 1;
  500. clarfg_(&i__2, &aii, &a[f2cmin(i__3,*m) + i__ * a_dim1], &c__1, &tau[
  501. i__]);
  502. i__2 = i__ + i__ * a_dim1;
  503. a[i__2].r = aii.r, a[i__2].i = aii.i;
  504. if (i__ < *n) {
  505. /* Apply H(i) to A(i:m,i+1:n) from the left */
  506. i__2 = i__ + i__ * a_dim1;
  507. aii.r = a[i__2].r, aii.i = a[i__2].i;
  508. i__2 = i__ + i__ * a_dim1;
  509. a[i__2].r = 1.f, a[i__2].i = 0.f;
  510. i__2 = *m - i__ + 1;
  511. i__3 = *n - i__;
  512. r_cnjg(&q__1, &tau[i__]);
  513. clarf_("Left", &i__2, &i__3, &a[i__ + i__ * a_dim1], &c__1, &
  514. q__1, &a[i__ + (i__ + 1) * a_dim1], lda, &work[1]);
  515. i__2 = i__ + i__ * a_dim1;
  516. a[i__2].r = aii.r, a[i__2].i = aii.i;
  517. }
  518. /* Update partial column norms */
  519. i__2 = *n;
  520. for (j = i__ + 1; j <= i__2; ++j) {
  521. if (rwork[j] != 0.f) {
  522. /* NOTE: The following 4 lines follow from the analysis in */
  523. /* Lapack Working Note 176. */
  524. temp = c_abs(&a[i__ + j * a_dim1]) / rwork[j];
  525. /* Computing MAX */
  526. r__1 = 0.f, r__2 = (temp + 1.f) * (1.f - temp);
  527. temp = f2cmax(r__1,r__2);
  528. /* Computing 2nd power */
  529. r__1 = rwork[j] / rwork[*n + j];
  530. temp2 = temp * (r__1 * r__1);
  531. if (temp2 <= tol3z) {
  532. if (*m - i__ > 0) {
  533. i__3 = *m - i__;
  534. rwork[j] = scnrm2_(&i__3, &a[i__ + 1 + j * a_dim1]
  535. , &c__1);
  536. rwork[*n + j] = rwork[j];
  537. } else {
  538. rwork[j] = 0.f;
  539. rwork[*n + j] = 0.f;
  540. }
  541. } else {
  542. rwork[j] *= sqrt(temp);
  543. }
  544. }
  545. /* L30: */
  546. }
  547. /* L40: */
  548. }
  549. }
  550. return;
  551. /* End of CGEQPF */
  552. } /* cgeqpf_ */