--- /dev/null
+#include "clapack.h"
+
+/* Table of constant values */
+
+static integer c__1 = 1;
+static integer c_n1 = -1;
+static integer c__3 = 3;
+static integer c__2 = 2;
+
+/* Subroutine */ int sorglq_(integer *m, integer *n, integer *k, real *a,
+ integer *lda, real *tau, real *work, integer *lwork, integer *info)
+{
+ /* System generated locals */
+ integer a_dim1, a_offset, i__1, i__2, i__3;
+
+ /* Local variables */
+ integer i__, j, l, ib, nb, ki, kk, nx, iws, nbmin, iinfo;
+ extern /* Subroutine */ int sorgl2_(integer *, integer *, integer *, real
+ *, integer *, real *, real *, integer *), slarfb_(char *, char *,
+ char *, char *, integer *, integer *, integer *, real *, integer *
+, real *, integer *, real *, integer *, real *, integer *), xerbla_(char *, integer *);
+ extern integer ilaenv_(integer *, char *, char *, integer *, integer *,
+ integer *, integer *);
+ extern /* Subroutine */ int slarft_(char *, char *, integer *, integer *,
+ real *, integer *, real *, real *, integer *);
+ integer ldwork, lwkopt;
+ logical lquery;
+
+
+/* -- LAPACK routine (version 3.1) -- */
+/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/* November 2006 */
+
+/* .. Scalar Arguments .. */
+/* .. */
+/* .. Array Arguments .. */
+/* .. */
+
+/* Purpose */
+/* ======= */
+
+/* SORGLQ generates an M-by-N real matrix Q with orthonormal rows, */
+/* which is defined as the first M rows of a product of K elementary */
+/* reflectors of order N */
+
+/* Q = H(k) . . . H(2) H(1) */
+
+/* as returned by SGELQF. */
+
+/* Arguments */
+/* ========= */
+
+/* M (input) INTEGER */
+/* The number of rows of the matrix Q. M >= 0. */
+
+/* N (input) INTEGER */
+/* The number of columns of the matrix Q. N >= M. */
+
+/* K (input) INTEGER */
+/* The number of elementary reflectors whose product defines the */
+/* matrix Q. M >= K >= 0. */
+
+/* A (input/output) REAL array, dimension (LDA,N) */
+/* On entry, the i-th row must contain the vector which defines */
+/* the elementary reflector H(i), for i = 1,2,...,k, as returned */
+/* by SGELQF in the first k rows of its array argument A. */
+/* On exit, the M-by-N matrix Q. */
+
+/* LDA (input) INTEGER */
+/* The first dimension of the array A. LDA >= max(1,M). */
+
+/* TAU (input) REAL array, dimension (K) */
+/* TAU(i) must contain the scalar factor of the elementary */
+/* reflector H(i), as returned by SGELQF. */
+
+/* WORK (workspace/output) REAL array, dimension (MAX(1,LWORK)) */
+/* On exit, if INFO = 0, WORK(1) returns the optimal LWORK. */
+
+/* LWORK (input) INTEGER */
+/* The dimension of the array WORK. LWORK >= max(1,M). */
+/* For optimum performance LWORK >= M*NB, where NB is */
+/* the optimal blocksize. */
+
+/* If LWORK = -1, then a workspace query is assumed; the routine */
+/* only calculates the optimal size of the WORK array, returns */
+/* this value as the first entry of the WORK array, and no error */
+/* message related to LWORK is issued by XERBLA. */
+
+/* INFO (output) INTEGER */
+/* = 0: successful exit */
+/* < 0: if INFO = -i, the i-th argument has an illegal value */
+
+/* ===================================================================== */
+
+/* .. Parameters .. */
+/* .. */
+/* .. Local Scalars .. */
+/* .. */
+/* .. External Subroutines .. */
+/* .. */
+/* .. Intrinsic Functions .. */
+/* .. */
+/* .. External Functions .. */
+/* .. */
+/* .. Executable Statements .. */
+
+/* Test the input arguments */
+
+ /* Parameter adjustments */
+ a_dim1 = *lda;
+ a_offset = 1 + a_dim1;
+ a -= a_offset;
+ --tau;
+ --work;
+
+ /* Function Body */
+ *info = 0;
+ nb = ilaenv_(&c__1, "SORGLQ", " ", m, n, k, &c_n1);
+ lwkopt = max(1,*m) * nb;
+ work[1] = (real) lwkopt;
+ lquery = *lwork == -1;
+ if (*m < 0) {
+ *info = -1;
+ } else if (*n < *m) {
+ *info = -2;
+ } else if (*k < 0 || *k > *m) {
+ *info = -3;
+ } else if (*lda < max(1,*m)) {
+ *info = -5;
+ } else if (*lwork < max(1,*m) && ! lquery) {
+ *info = -8;
+ }
+ if (*info != 0) {
+ i__1 = -(*info);
+ xerbla_("SORGLQ", &i__1);
+ return 0;
+ } else if (lquery) {
+ return 0;
+ }
+
+/* Quick return if possible */
+
+ if (*m <= 0) {
+ work[1] = 1.f;
+ return 0;
+ }
+
+ nbmin = 2;
+ nx = 0;
+ iws = *m;
+ if (nb > 1 && nb < *k) {
+
+/* Determine when to cross over from blocked to unblocked code. */
+
+/* Computing MAX */
+ i__1 = 0, i__2 = ilaenv_(&c__3, "SORGLQ", " ", m, n, k, &c_n1);
+ nx = max(i__1,i__2);
+ if (nx < *k) {
+
+/* Determine if workspace is large enough for blocked code. */
+
+ ldwork = *m;
+ iws = ldwork * nb;
+ if (*lwork < iws) {
+
+/* Not enough workspace to use optimal NB: reduce NB and */
+/* determine the minimum value of NB. */
+
+ nb = *lwork / ldwork;
+/* Computing MAX */
+ i__1 = 2, i__2 = ilaenv_(&c__2, "SORGLQ", " ", m, n, k, &c_n1);
+ nbmin = max(i__1,i__2);
+ }
+ }
+ }
+
+ if (nb >= nbmin && nb < *k && nx < *k) {
+
+/* Use blocked code after the last block. */
+/* The first kk rows are handled by the block method. */
+
+ ki = (*k - nx - 1) / nb * nb;
+/* Computing MIN */
+ i__1 = *k, i__2 = ki + nb;
+ kk = min(i__1,i__2);
+
+/* Set A(kk+1:m,1:kk) to zero. */
+
+ i__1 = kk;
+ for (j = 1; j <= i__1; ++j) {
+ i__2 = *m;
+ for (i__ = kk + 1; i__ <= i__2; ++i__) {
+ a[i__ + j * a_dim1] = 0.f;
+/* L10: */
+ }
+/* L20: */
+ }
+ } else {
+ kk = 0;
+ }
+
+/* Use unblocked code for the last or only block. */
+
+ if (kk < *m) {
+ i__1 = *m - kk;
+ i__2 = *n - kk;
+ i__3 = *k - kk;
+ sorgl2_(&i__1, &i__2, &i__3, &a[kk + 1 + (kk + 1) * a_dim1], lda, &
+ tau[kk + 1], &work[1], &iinfo);
+ }
+
+ if (kk > 0) {
+
+/* Use blocked code */
+
+ i__1 = -nb;
+ for (i__ = ki + 1; i__1 < 0 ? i__ >= 1 : i__ <= 1; i__ += i__1) {
+/* Computing MIN */
+ i__2 = nb, i__3 = *k - i__ + 1;
+ ib = min(i__2,i__3);
+ if (i__ + ib <= *m) {
+
+/* Form the triangular factor of the block reflector */
+/* H = H(i) H(i+1) . . . H(i+ib-1) */
+
+ i__2 = *n - i__ + 1;
+ slarft_("Forward", "Rowwise", &i__2, &ib, &a[i__ + i__ *
+ a_dim1], lda, &tau[i__], &work[1], &ldwork);
+
+/* Apply H' to A(i+ib:m,i:n) from the right */
+
+ i__2 = *m - i__ - ib + 1;
+ i__3 = *n - i__ + 1;
+ slarfb_("Right", "Transpose", "Forward", "Rowwise", &i__2, &
+ i__3, &ib, &a[i__ + i__ * a_dim1], lda, &work[1], &
+ ldwork, &a[i__ + ib + i__ * a_dim1], lda, &work[ib +
+ 1], &ldwork);
+ }
+
+/* Apply H' to columns i:n of current block */
+
+ i__2 = *n - i__ + 1;
+ sorgl2_(&ib, &i__2, &ib, &a[i__ + i__ * a_dim1], lda, &tau[i__], &
+ work[1], &iinfo);
+
+/* Set columns 1:i-1 of current block to zero */
+
+ i__2 = i__ - 1;
+ for (j = 1; j <= i__2; ++j) {
+ i__3 = i__ + ib - 1;
+ for (l = i__; l <= i__3; ++l) {
+ a[l + j * a_dim1] = 0.f;
+/* L30: */
+ }
+/* L40: */
+ }
+/* L50: */
+ }
+ }
+
+ work[1] = (real) iws;
+ return 0;
+
+/* End of SORGLQ */
+
+} /* sorglq_ */
projects / opencv / blobdiff