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dgeqpf.c 17 kB

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  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 char integer1;
  52. #define TRUE_ (1)
  53. #define FALSE_ (0)
  54. /* Extern is for use with -E */
  55. #ifndef Extern
  56. #define Extern extern
  57. #endif
  58. /* I/O stuff */
  59. typedef int flag;
  60. typedef int ftnlen;
  61. typedef int ftnint;
  62. /*external read, write*/
  63. typedef struct
  64. { flag cierr;
  65. ftnint ciunit;
  66. flag ciend;
  67. char *cifmt;
  68. ftnint cirec;
  69. } cilist;
  70. /*internal read, write*/
  71. typedef struct
  72. { flag icierr;
  73. char *iciunit;
  74. flag iciend;
  75. char *icifmt;
  76. ftnint icirlen;
  77. ftnint icirnum;
  78. } icilist;
  79. /*open*/
  80. typedef struct
  81. { flag oerr;
  82. ftnint ounit;
  83. char *ofnm;
  84. ftnlen ofnmlen;
  85. char *osta;
  86. char *oacc;
  87. char *ofm;
  88. ftnint orl;
  89. char *oblnk;
  90. } olist;
  91. /*close*/
  92. typedef struct
  93. { flag cerr;
  94. ftnint cunit;
  95. char *csta;
  96. } cllist;
  97. /*rewind, backspace, endfile*/
  98. typedef struct
  99. { flag aerr;
  100. ftnint aunit;
  101. } alist;
  102. /* inquire */
  103. typedef struct
  104. { flag inerr;
  105. ftnint inunit;
  106. char *infile;
  107. ftnlen infilen;
  108. ftnint *inex; /*parameters in standard's order*/
  109. ftnint *inopen;
  110. ftnint *innum;
  111. ftnint *innamed;
  112. char *inname;
  113. ftnlen innamlen;
  114. char *inacc;
  115. ftnlen inacclen;
  116. char *inseq;
  117. ftnlen inseqlen;
  118. char *indir;
  119. ftnlen indirlen;
  120. char *infmt;
  121. ftnlen infmtlen;
  122. char *inform;
  123. ftnint informlen;
  124. char *inunf;
  125. ftnlen inunflen;
  126. ftnint *inrecl;
  127. ftnint *innrec;
  128. char *inblank;
  129. ftnlen inblanklen;
  130. } inlist;
  131. #define VOID void
  132. union Multitype { /* for multiple entry points */
  133. integer1 g;
  134. shortint h;
  135. integer i;
  136. /* longint j; */
  137. real r;
  138. doublereal d;
  139. complex c;
  140. doublecomplex z;
  141. };
  142. typedef union Multitype Multitype;
  143. struct Vardesc { /* for Namelist */
  144. char *name;
  145. char *addr;
  146. ftnlen *dims;
  147. int type;
  148. };
  149. typedef struct Vardesc Vardesc;
  150. struct Namelist {
  151. char *name;
  152. Vardesc **vars;
  153. int nvars;
  154. };
  155. typedef struct Namelist Namelist;
  156. #define abs(x) ((x) >= 0 ? (x) : -(x))
  157. #define dabs(x) (fabs(x))
  158. #define f2cmin(a,b) ((a) <= (b) ? (a) : (b))
  159. #define f2cmax(a,b) ((a) >= (b) ? (a) : (b))
  160. #define dmin(a,b) (f2cmin(a,b))
  161. #define dmax(a,b) (f2cmax(a,b))
  162. #define bit_test(a,b) ((a) >> (b) & 1)
  163. #define bit_clear(a,b) ((a) & ~((uinteger)1 << (b)))
  164. #define bit_set(a,b) ((a) | ((uinteger)1 << (b)))
  165. #define abort_() { sig_die("Fortran abort routine called", 1); }
  166. #define c_abs(z) (cabsf(Cf(z)))
  167. #define c_cos(R,Z) { pCf(R)=ccos(Cf(Z)); }
  168. #ifdef _MSC_VER
  169. #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]);}
  170. #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]);}
  171. #else
  172. #define c_div(c, a, b) {pCf(c) = Cf(a)/Cf(b);}
  173. #define z_div(c, a, b) {pCd(c) = Cd(a)/Cd(b);}
  174. #endif
  175. #define c_exp(R, Z) {pCf(R) = cexpf(Cf(Z));}
  176. #define c_log(R, Z) {pCf(R) = clogf(Cf(Z));}
  177. #define c_sin(R, Z) {pCf(R) = csinf(Cf(Z));}
  178. //#define c_sqrt(R, Z) {*(R) = csqrtf(Cf(Z));}
  179. #define c_sqrt(R, Z) {pCf(R) = csqrtf(Cf(Z));}
  180. #define d_abs(x) (fabs(*(x)))
  181. #define d_acos(x) (acos(*(x)))
  182. #define d_asin(x) (asin(*(x)))
  183. #define d_atan(x) (atan(*(x)))
  184. #define d_atn2(x, y) (atan2(*(x),*(y)))
  185. #define d_cnjg(R, Z) { pCd(R) = conj(Cd(Z)); }
  186. #define r_cnjg(R, Z) { pCf(R) = conjf(Cf(Z)); }
  187. #define d_cos(x) (cos(*(x)))
  188. #define d_cosh(x) (cosh(*(x)))
  189. #define d_dim(__a, __b) ( *(__a) > *(__b) ? *(__a) - *(__b) : 0.0 )
  190. #define d_exp(x) (exp(*(x)))
  191. #define d_imag(z) (cimag(Cd(z)))
  192. #define r_imag(z) (cimagf(Cf(z)))
  193. #define d_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
  194. #define r_int(__x) (*(__x)>0 ? floor(*(__x)) : -floor(- *(__x)))
  195. #define d_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
  196. #define r_lg10(x) ( 0.43429448190325182765 * log(*(x)) )
  197. #define d_log(x) (log(*(x)))
  198. #define d_mod(x, y) (fmod(*(x), *(y)))
  199. #define u_nint(__x) ((__x)>=0 ? floor((__x) + .5) : -floor(.5 - (__x)))
  200. #define d_nint(x) u_nint(*(x))
  201. #define u_sign(__a,__b) ((__b) >= 0 ? ((__a) >= 0 ? (__a) : -(__a)) : -((__a) >= 0 ? (__a) : -(__a)))
  202. #define d_sign(a,b) u_sign(*(a),*(b))
  203. #define r_sign(a,b) u_sign(*(a),*(b))
  204. #define d_sin(x) (sin(*(x)))
  205. #define d_sinh(x) (sinh(*(x)))
  206. #define d_sqrt(x) (sqrt(*(x)))
  207. #define d_tan(x) (tan(*(x)))
  208. #define d_tanh(x) (tanh(*(x)))
  209. #define i_abs(x) abs(*(x))
  210. #define i_dnnt(x) ((integer)u_nint(*(x)))
  211. #define i_len(s, n) (n)
  212. #define i_nint(x) ((integer)u_nint(*(x)))
  213. #define i_sign(a,b) ((integer)u_sign((integer)*(a),(integer)*(b)))
  214. #define pow_dd(ap, bp) ( pow(*(ap), *(bp)))
  215. #define pow_si(B,E) spow_ui(*(B),*(E))
  216. #define pow_ri(B,E) spow_ui(*(B),*(E))
  217. #define pow_di(B,E) dpow_ui(*(B),*(E))
  218. #define pow_zi(p, a, b) {pCd(p) = zpow_ui(Cd(a), *(b));}
  219. #define pow_ci(p, a, b) {pCf(p) = cpow_ui(Cf(a), *(b));}
  220. #define pow_zz(R,A,B) {pCd(R) = cpow(Cd(A),*(B));}
  221. #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++ = ' '; }
  222. #define s_cmp(a,b,c,d) ((integer)strncmp((a),(b),f2cmin((c),(d))))
  223. #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]; }
  224. #define sig_die(s, kill) { exit(1); }
  225. #define s_stop(s, n) {exit(0);}
  226. #define z_abs(z) (cabs(Cd(z)))
  227. #define z_exp(R, Z) {pCd(R) = cexp(Cd(Z));}
  228. #define z_sqrt(R, Z) {pCd(R) = csqrt(Cd(Z));}
  229. #define myexit_() break;
  230. #define mycycle() continue;
  231. #define myceiling(w) {ceil(w)}
  232. #define myhuge(w) {HUGE_VAL}
  233. //#define mymaxloc_(w,s,e,n) {if (sizeof(*(w)) == sizeof(double)) dmaxloc_((w),*(s),*(e),n); else dmaxloc_((w),*(s),*(e),n);}
  234. #define mymaxloc(w,s,e,n) {dmaxloc_(w,*(s),*(e),n)}
  235. /* procedure parameter types for -A and -C++ */
  236. /*
  237. You must link the resulting object file with the libraries:
  238. -lf2c -lm (in that order)
  239. */
  240. /* Table of constant values */
  241. static integer c__1 = 1;
  242. /* > \brief \b DGEQPF */
  243. /* =========== DOCUMENTATION =========== */
  244. /* Online html documentation available at */
  245. /* http://www.netlib.org/lapack/explore-html/ */
  246. /* > \htmlonly */
  247. /* > Download DGEQPF + dependencies */
  248. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dgeqpf.
  249. f"> */
  250. /* > [TGZ]</a> */
  251. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dgeqpf.
  252. f"> */
  253. /* > [ZIP]</a> */
  254. /* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dgeqpf.
  255. f"> */
  256. /* > [TXT]</a> */
  257. /* > \endhtmlonly */
  258. /* Definition: */
  259. /* =========== */
  260. /* SUBROUTINE DGEQPF( M, N, A, LDA, JPVT, TAU, WORK, INFO ) */
  261. /* INTEGER INFO, LDA, M, N */
  262. /* INTEGER JPVT( * ) */
  263. /* DOUBLE PRECISION A( LDA, * ), TAU( * ), WORK( * ) */
  264. /* > \par Purpose: */
  265. /* ============= */
  266. /* > */
  267. /* > \verbatim */
  268. /* > */
  269. /* > This routine is deprecated and has been replaced by routine DGEQP3. */
  270. /* > */
  271. /* > DGEQPF computes a QR factorization with column pivoting of a */
  272. /* > real M-by-N matrix A: A*P = Q*R. */
  273. /* > \endverbatim */
  274. /* Arguments: */
  275. /* ========== */
  276. /* > \param[in] M */
  277. /* > \verbatim */
  278. /* > M is INTEGER */
  279. /* > The number of rows of the matrix A. M >= 0. */
  280. /* > \endverbatim */
  281. /* > */
  282. /* > \param[in] N */
  283. /* > \verbatim */
  284. /* > N is INTEGER */
  285. /* > The number of columns of the matrix A. N >= 0 */
  286. /* > \endverbatim */
  287. /* > */
  288. /* > \param[in,out] A */
  289. /* > \verbatim */
  290. /* > A is DOUBLE PRECISION array, dimension (LDA,N) */
  291. /* > On entry, the M-by-N matrix A. */
  292. /* > On exit, the upper triangle of the array contains the */
  293. /* > f2cmin(M,N)-by-N upper triangular matrix R; the elements */
  294. /* > below the diagonal, together with the array TAU, */
  295. /* > represent the orthogonal matrix Q as a product of */
  296. /* > f2cmin(m,n) elementary reflectors. */
  297. /* > \endverbatim */
  298. /* > */
  299. /* > \param[in] LDA */
  300. /* > \verbatim */
  301. /* > LDA is INTEGER */
  302. /* > The leading dimension of the array A. LDA >= f2cmax(1,M). */
  303. /* > \endverbatim */
  304. /* > */
  305. /* > \param[in,out] JPVT */
  306. /* > \verbatim */
  307. /* > JPVT is INTEGER array, dimension (N) */
  308. /* > On entry, if JPVT(i) .ne. 0, the i-th column of A is permuted */
  309. /* > to the front of A*P (a leading column); if JPVT(i) = 0, */
  310. /* > the i-th column of A is a free column. */
  311. /* > On exit, if JPVT(i) = k, then the i-th column of A*P */
  312. /* > was the k-th column of A. */
  313. /* > \endverbatim */
  314. /* > */
  315. /* > \param[out] TAU */
  316. /* > \verbatim */
  317. /* > TAU is DOUBLE PRECISION array, dimension (f2cmin(M,N)) */
  318. /* > The scalar factors of the elementary reflectors. */
  319. /* > \endverbatim */
  320. /* > */
  321. /* > \param[out] WORK */
  322. /* > \verbatim */
  323. /* > WORK is DOUBLE PRECISION array, dimension (3*N) */
  324. /* > \endverbatim */
  325. /* > */
  326. /* > \param[out] INFO */
  327. /* > \verbatim */
  328. /* > INFO is INTEGER */
  329. /* > = 0: successful exit */
  330. /* > < 0: if INFO = -i, the i-th argument had an illegal value */
  331. /* > \endverbatim */
  332. /* Authors: */
  333. /* ======== */
  334. /* > \author Univ. of Tennessee */
  335. /* > \author Univ. of California Berkeley */
  336. /* > \author Univ. of Colorado Denver */
  337. /* > \author NAG Ltd. */
  338. /* > \date December 2016 */
  339. /* > \ingroup doubleGEcomputational */
  340. /* > \par Further Details: */
  341. /* ===================== */
  342. /* > */
  343. /* > \verbatim */
  344. /* > */
  345. /* > The matrix Q is represented as a product of elementary reflectors */
  346. /* > */
  347. /* > Q = H(1) H(2) . . . H(n) */
  348. /* > */
  349. /* > Each H(i) has the form */
  350. /* > */
  351. /* > H = I - tau * v * v**T */
  352. /* > */
  353. /* > where tau is a real scalar, and v is a real vector with */
  354. /* > v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i). */
  355. /* > */
  356. /* > The matrix P is represented in jpvt as follows: If */
  357. /* > jpvt(j) = i */
  358. /* > then the jth column of P is the ith canonical unit vector. */
  359. /* > */
  360. /* > Partial column norm updating strategy modified by */
  361. /* > Z. Drmac and Z. Bujanovic, Dept. of Mathematics, */
  362. /* > University of Zagreb, Croatia. */
  363. /* > -- April 2011 -- */
  364. /* > For more details see LAPACK Working Note 176. */
  365. /* > \endverbatim */
  366. /* > */
  367. /* ===================================================================== */
  368. /* Subroutine */ void dgeqpf_(integer *m, integer *n, doublereal *a, integer *
  369. lda, integer *jpvt, doublereal *tau, doublereal *work, integer *info)
  370. {
  371. /* System generated locals */
  372. integer a_dim1, a_offset, i__1, i__2, i__3;
  373. doublereal d__1, d__2;
  374. /* Local variables */
  375. doublereal temp;
  376. extern doublereal dnrm2_(integer *, doublereal *, integer *);
  377. doublereal temp2;
  378. integer i__, j;
  379. doublereal tol3z;
  380. extern /* Subroutine */ void dlarf_(char *, integer *, integer *,
  381. doublereal *, integer *, doublereal *, doublereal *, integer *,
  382. doublereal *);
  383. integer itemp;
  384. extern /* Subroutine */ void dswap_(integer *, doublereal *, integer *,
  385. doublereal *, integer *), dgeqr2_(integer *, integer *,
  386. doublereal *, integer *, doublereal *, doublereal *, integer *),
  387. dorm2r_(char *, char *, integer *, integer *, integer *,
  388. doublereal *, integer *, doublereal *, doublereal *, integer *,
  389. doublereal *, integer *);
  390. integer ma;
  391. extern doublereal dlamch_(char *);
  392. integer mn;
  393. extern /* Subroutine */ void dlarfg_(integer *, doublereal *, doublereal *,
  394. integer *, doublereal *);
  395. extern integer idamax_(integer *, doublereal *, integer *);
  396. extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
  397. doublereal aii;
  398. integer pvt;
  399. /* -- LAPACK computational routine (version 3.7.0) -- */
  400. /* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
  401. /* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
  402. /* December 2016 */
  403. /* ===================================================================== */
  404. /* Test the input arguments */
  405. /* Parameter adjustments */
  406. a_dim1 = *lda;
  407. a_offset = 1 + a_dim1 * 1;
  408. a -= a_offset;
  409. --jpvt;
  410. --tau;
  411. --work;
  412. /* Function Body */
  413. *info = 0;
  414. if (*m < 0) {
  415. *info = -1;
  416. } else if (*n < 0) {
  417. *info = -2;
  418. } else if (*lda < f2cmax(1,*m)) {
  419. *info = -4;
  420. }
  421. if (*info != 0) {
  422. i__1 = -(*info);
  423. xerbla_("DGEQPF", &i__1, 6);
  424. return;
  425. }
  426. mn = f2cmin(*m,*n);
  427. tol3z = sqrt(dlamch_("Epsilon"));
  428. /* Move initial columns up front */
  429. itemp = 1;
  430. i__1 = *n;
  431. for (i__ = 1; i__ <= i__1; ++i__) {
  432. if (jpvt[i__] != 0) {
  433. if (i__ != itemp) {
  434. dswap_(m, &a[i__ * a_dim1 + 1], &c__1, &a[itemp * a_dim1 + 1],
  435. &c__1);
  436. jpvt[i__] = jpvt[itemp];
  437. jpvt[itemp] = i__;
  438. } else {
  439. jpvt[i__] = i__;
  440. }
  441. ++itemp;
  442. } else {
  443. jpvt[i__] = i__;
  444. }
  445. /* L10: */
  446. }
  447. --itemp;
  448. /* Compute the QR factorization and update remaining columns */
  449. if (itemp > 0) {
  450. ma = f2cmin(itemp,*m);
  451. dgeqr2_(m, &ma, &a[a_offset], lda, &tau[1], &work[1], info);
  452. if (ma < *n) {
  453. i__1 = *n - ma;
  454. dorm2r_("Left", "Transpose", m, &i__1, &ma, &a[a_offset], lda, &
  455. tau[1], &a[(ma + 1) * a_dim1 + 1], lda, &work[1], info);
  456. }
  457. }
  458. if (itemp < mn) {
  459. /* Initialize partial column norms. The first n elements of */
  460. /* work store the exact column norms. */
  461. i__1 = *n;
  462. for (i__ = itemp + 1; i__ <= i__1; ++i__) {
  463. i__2 = *m - itemp;
  464. work[i__] = dnrm2_(&i__2, &a[itemp + 1 + i__ * a_dim1], &c__1);
  465. work[*n + i__] = work[i__];
  466. /* L20: */
  467. }
  468. /* Compute factorization */
  469. i__1 = mn;
  470. for (i__ = itemp + 1; i__ <= i__1; ++i__) {
  471. /* Determine ith pivot column and swap if necessary */
  472. i__2 = *n - i__ + 1;
  473. pvt = i__ - 1 + idamax_(&i__2, &work[i__], &c__1);
  474. if (pvt != i__) {
  475. dswap_(m, &a[pvt * a_dim1 + 1], &c__1, &a[i__ * a_dim1 + 1], &
  476. c__1);
  477. itemp = jpvt[pvt];
  478. jpvt[pvt] = jpvt[i__];
  479. jpvt[i__] = itemp;
  480. work[pvt] = work[i__];
  481. work[*n + pvt] = work[*n + i__];
  482. }
  483. /* Generate elementary reflector H(i) */
  484. if (i__ < *m) {
  485. i__2 = *m - i__ + 1;
  486. dlarfg_(&i__2, &a[i__ + i__ * a_dim1], &a[i__ + 1 + i__ *
  487. a_dim1], &c__1, &tau[i__]);
  488. } else {
  489. dlarfg_(&c__1, &a[*m + *m * a_dim1], &a[*m + *m * a_dim1], &
  490. c__1, &tau[*m]);
  491. }
  492. if (i__ < *n) {
  493. /* Apply H(i) to A(i:m,i+1:n) from the left */
  494. aii = a[i__ + i__ * a_dim1];
  495. a[i__ + i__ * a_dim1] = 1.;
  496. i__2 = *m - i__ + 1;
  497. i__3 = *n - i__;
  498. dlarf_("LEFT", &i__2, &i__3, &a[i__ + i__ * a_dim1], &c__1, &
  499. tau[i__], &a[i__ + (i__ + 1) * a_dim1], lda, &work[(*
  500. n << 1) + 1]);
  501. a[i__ + i__ * a_dim1] = aii;
  502. }
  503. /* Update partial column norms */
  504. i__2 = *n;
  505. for (j = i__ + 1; j <= i__2; ++j) {
  506. if (work[j] != 0.) {
  507. /* NOTE: The following 4 lines follow from the analysis in */
  508. /* Lapack Working Note 176. */
  509. temp = (d__1 = a[i__ + j * a_dim1], abs(d__1)) / work[j];
  510. /* Computing MAX */
  511. d__1 = 0., d__2 = (temp + 1.) * (1. - temp);
  512. temp = f2cmax(d__1,d__2);
  513. /* Computing 2nd power */
  514. d__1 = work[j] / work[*n + j];
  515. temp2 = temp * (d__1 * d__1);
  516. if (temp2 <= tol3z) {
  517. if (*m - i__ > 0) {
  518. i__3 = *m - i__;
  519. work[j] = dnrm2_(&i__3, &a[i__ + 1 + j * a_dim1],
  520. &c__1);
  521. work[*n + j] = work[j];
  522. } else {
  523. work[j] = 0.;
  524. work[*n + j] = 0.;
  525. }
  526. } else {
  527. work[j] *= sqrt(temp);
  528. }
  529. }
  530. /* L30: */
  531. }
  532. /* L40: */
  533. }
  534. }
  535. return;
  536. /* End of DGEQPF */
  537. } /* dgeqpf_ */