--- /dev/null
+#include "clapack.h"
+
+/* Table of constant values */
+
+static integer c__1 = 1;
+static integer c_n1 = -1;
+
+/* Subroutine */ int sorgbr_(char *vect, 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, nb, mn;
+ extern logical lsame_(char *, char *);
+ integer iinfo;
+ logical wantq;
+ extern /* Subroutine */ int xerbla_(char *, integer *);
+ extern integer ilaenv_(integer *, char *, char *, integer *, integer *,
+ integer *, integer *);
+ extern /* Subroutine */ int sorglq_(integer *, integer *, integer *, real
+ *, integer *, real *, real *, integer *, integer *), sorgqr_(
+ integer *, integer *, integer *, real *, integer *, real *, real *
+, integer *, integer *);
+ integer 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 */
+/* ======= */
+
+/* SORGBR generates one of the real orthogonal matrices Q or P**T */
+/* determined by SGEBRD when reducing a real matrix A to bidiagonal */
+/* form: A = Q * B * P**T. Q and P**T are defined as products of */
+/* elementary reflectors H(i) or G(i) respectively. */
+
+/* If VECT = 'Q', A is assumed to have been an M-by-K matrix, and Q */
+/* is of order M: */
+/* if m >= k, Q = H(1) H(2) . . . H(k) and SORGBR returns the first n */
+/* columns of Q, where m >= n >= k; */
+/* if m < k, Q = H(1) H(2) . . . H(m-1) and SORGBR returns Q as an */
+/* M-by-M matrix. */
+
+/* If VECT = 'P', A is assumed to have been a K-by-N matrix, and P**T */
+/* is of order N: */
+/* if k < n, P**T = G(k) . . . G(2) G(1) and SORGBR returns the first m */
+/* rows of P**T, where n >= m >= k; */
+/* if k >= n, P**T = G(n-1) . . . G(2) G(1) and SORGBR returns P**T as */
+/* an N-by-N matrix. */
+
+/* Arguments */
+/* ========= */
+
+/* VECT (input) CHARACTER*1 */
+/* Specifies whether the matrix Q or the matrix P**T is */
+/* required, as defined in the transformation applied by SGEBRD: */
+/* = 'Q': generate Q; */
+/* = 'P': generate P**T. */
+
+/* M (input) INTEGER */
+/* The number of rows of the matrix Q or P**T to be returned. */
+/* M >= 0. */
+
+/* N (input) INTEGER */
+/* The number of columns of the matrix Q or P**T to be returned. */
+/* N >= 0. */
+/* If VECT = 'Q', M >= N >= min(M,K); */
+/* if VECT = 'P', N >= M >= min(N,K). */
+
+/* K (input) INTEGER */
+/* If VECT = 'Q', the number of columns in the original M-by-K */
+/* matrix reduced by SGEBRD. */
+/* If VECT = 'P', the number of rows in the original K-by-N */
+/* matrix reduced by SGEBRD. */
+/* K >= 0. */
+
+/* A (input/output) REAL array, dimension (LDA,N) */
+/* On entry, the vectors which define the elementary reflectors, */
+/* as returned by SGEBRD. */
+/* On exit, the M-by-N matrix Q or P**T. */
+
+/* LDA (input) INTEGER */
+/* The leading dimension of the array A. LDA >= max(1,M). */
+
+/* TAU (input) REAL array, dimension */
+/* (min(M,K)) if VECT = 'Q' */
+/* (min(N,K)) if VECT = 'P' */
+/* TAU(i) must contain the scalar factor of the elementary */
+/* reflector H(i) or G(i), which determines Q or P**T, as */
+/* returned by SGEBRD in its array argument TAUQ or TAUP. */
+
+/* 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,min(M,N)). */
+/* For optimum performance LWORK >= min(M,N)*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 had an illegal value */
+
+/* ===================================================================== */
+
+/* .. Parameters .. */
+/* .. */
+/* .. Local Scalars .. */
+/* .. */
+/* .. External Functions .. */
+/* .. */
+/* .. External Subroutines .. */
+/* .. */
+/* .. Intrinsic 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;
+ wantq = lsame_(vect, "Q");
+ mn = min(*m,*n);
+ lquery = *lwork == -1;
+ if (! wantq && ! lsame_(vect, "P")) {
+ *info = -1;
+ } else if (*m < 0) {
+ *info = -2;
+ } else if (*n < 0 || wantq && (*n > *m || *n < min(*m,*k)) || ! wantq && (
+ *m > *n || *m < min(*n,*k))) {
+ *info = -3;
+ } else if (*k < 0) {
+ *info = -4;
+ } else if (*lda < max(1,*m)) {
+ *info = -6;
+ } else if (*lwork < max(1,mn) && ! lquery) {
+ *info = -9;
+ }
+
+ if (*info == 0) {
+ if (wantq) {
+ nb = ilaenv_(&c__1, "SORGQR", " ", m, n, k, &c_n1);
+ } else {
+ nb = ilaenv_(&c__1, "SORGLQ", " ", m, n, k, &c_n1);
+ }
+ lwkopt = max(1,mn) * nb;
+ work[1] = (real) lwkopt;
+ }
+
+ if (*info != 0) {
+ i__1 = -(*info);
+ xerbla_("SORGBR", &i__1);
+ return 0;
+ } else if (lquery) {
+ return 0;
+ }
+
+/* Quick return if possible */
+
+ if (*m == 0 || *n == 0) {
+ work[1] = 1.f;
+ return 0;
+ }
+
+ if (wantq) {
+
+/* Form Q, determined by a call to SGEBRD to reduce an m-by-k */
+/* matrix */
+
+ if (*m >= *k) {
+
+/* If m >= k, assume m >= n >= k */
+
+ sorgqr_(m, n, k, &a[a_offset], lda, &tau[1], &work[1], lwork, &
+ iinfo);
+
+ } else {
+
+/* If m < k, assume m = n */
+
+/* Shift the vectors which define the elementary reflectors one */
+/* column to the right, and set the first row and column of Q */
+/* to those of the unit matrix */
+
+ for (j = *m; j >= 2; --j) {
+ a[j * a_dim1 + 1] = 0.f;
+ i__1 = *m;
+ for (i__ = j + 1; i__ <= i__1; ++i__) {
+ a[i__ + j * a_dim1] = a[i__ + (j - 1) * a_dim1];
+/* L10: */
+ }
+/* L20: */
+ }
+ a[a_dim1 + 1] = 1.f;
+ i__1 = *m;
+ for (i__ = 2; i__ <= i__1; ++i__) {
+ a[i__ + a_dim1] = 0.f;
+/* L30: */
+ }
+ if (*m > 1) {
+
+/* Form Q(2:m,2:m) */
+
+ i__1 = *m - 1;
+ i__2 = *m - 1;
+ i__3 = *m - 1;
+ sorgqr_(&i__1, &i__2, &i__3, &a[(a_dim1 << 1) + 2], lda, &tau[
+ 1], &work[1], lwork, &iinfo);
+ }
+ }
+ } else {
+
+/* Form P', determined by a call to SGEBRD to reduce a k-by-n */
+/* matrix */
+
+ if (*k < *n) {
+
+/* If k < n, assume k <= m <= n */
+
+ sorglq_(m, n, k, &a[a_offset], lda, &tau[1], &work[1], lwork, &
+ iinfo);
+
+ } else {
+
+/* If k >= n, assume m = n */
+
+/* Shift the vectors which define the elementary reflectors one */
+/* row downward, and set the first row and column of P' to */
+/* those of the unit matrix */
+
+ a[a_dim1 + 1] = 1.f;
+ i__1 = *n;
+ for (i__ = 2; i__ <= i__1; ++i__) {
+ a[i__ + a_dim1] = 0.f;
+/* L40: */
+ }
+ i__1 = *n;
+ for (j = 2; j <= i__1; ++j) {
+ for (i__ = j - 1; i__ >= 2; --i__) {
+ a[i__ + j * a_dim1] = a[i__ - 1 + j * a_dim1];
+/* L50: */
+ }
+ a[j * a_dim1 + 1] = 0.f;
+/* L60: */
+ }
+ if (*n > 1) {
+
+/* Form P'(2:n,2:n) */
+
+ i__1 = *n - 1;
+ i__2 = *n - 1;
+ i__3 = *n - 1;
+ sorglq_(&i__1, &i__2, &i__3, &a[(a_dim1 << 1) + 2], lda, &tau[
+ 1], &work[1], lwork, &iinfo);
+ }
+ }
+ }
+ work[1] = (real) lwkopt;
+ return 0;
+
+/* End of SORGBR */
+
+} /* sorgbr_ */
projects / opencv / blobdiff