Subroutine */
| 7999 | } /* slabad_ */ |
| 8000 | |
| 8001 | /* Subroutine */ int slabrd_(integer *m, integer *n, integer *nb, real *a, |
| 8002 | integer *lda, real *d__, real *e, real *tauq, real *taup, real *x, |
| 8003 | integer *ldx, real *y, integer *ldy) |
| 8004 | { |
| 8005 | /* System generated locals */ |
| 8006 | integer a_dim1, a_offset, x_dim1, x_offset, y_dim1, y_offset, i__1, i__2, |
| 8007 | i__3; |
| 8008 | |
| 8009 | /* Local variables */ |
| 8010 | static integer i__; |
| 8011 | extern /* Subroutine */ int sscal_(integer *, real *, real *, integer *), |
| 8012 | sgemv_(char *, integer *, integer *, real *, real *, integer *, |
| 8013 | real *, integer *, real *, real *, integer *), slarfg_( |
| 8014 | integer *, real *, real *, integer *, real *); |
| 8015 | |
| 8016 | |
| 8017 | /* |
| 8018 | -- LAPACK auxiliary routine (version 3.2) -- |
| 8019 | -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| 8020 | -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| 8021 | November 2006 |
| 8022 | |
| 8023 | |
| 8024 | Purpose |
| 8025 | ======= |
| 8026 | |
| 8027 | SLABRD reduces the first NB rows and columns of a real general |
| 8028 | m by n matrix A to upper or lower bidiagonal form by an orthogonal |
| 8029 | transformation Q' * A * P, and returns the matrices X and Y which |
| 8030 | are needed to apply the transformation to the unreduced part of A. |
| 8031 | |
| 8032 | If m >= n, A is reduced to upper bidiagonal form; if m < n, to lower |
| 8033 | bidiagonal form. |
| 8034 | |
| 8035 | This is an auxiliary routine called by SGEBRD |
| 8036 | |
| 8037 | Arguments |
| 8038 | ========= |
| 8039 | |
| 8040 | M (input) INTEGER |
| 8041 | The number of rows in the matrix A. |
| 8042 | |
| 8043 | N (input) INTEGER |
| 8044 | The number of columns in the matrix A. |
| 8045 | |
| 8046 | NB (input) INTEGER |
| 8047 | The number of leading rows and columns of A to be reduced. |
| 8048 | |
| 8049 | A (input/output) REAL array, dimension (LDA,N) |
| 8050 | On entry, the m by n general matrix to be reduced. |
| 8051 | On exit, the first NB rows and columns of the matrix are |
| 8052 | overwritten; the rest of the array is unchanged. |
| 8053 | If m >= n, elements on and below the diagonal in the first NB |
| 8054 | columns, with the array TAUQ, represent the orthogonal |
| 8055 | matrix Q as a product of elementary reflectors; and |
| 8056 | elements above the diagonal in the first NB rows, with the |
| 8057 | array TAUP, represent the orthogonal matrix P as a product |
| 8058 | of elementary reflectors. |