Subroutine */
| 33190 | } /* dlauum_ */ |
| 33191 | |
| 33192 | /* Subroutine */ int dorg2r_(integer *m, integer *n, integer *k, doublereal * |
| 33193 | a, integer *lda, doublereal *tau, doublereal *work, integer *info) |
| 33194 | { |
| 33195 | /* System generated locals */ |
| 33196 | integer a_dim1, a_offset, i__1, i__2; |
| 33197 | doublereal d__1; |
| 33198 | |
| 33199 | /* Local variables */ |
| 33200 | static integer i__, j, l; |
| 33201 | extern /* Subroutine */ int dscal_(integer *, doublereal *, doublereal *, |
| 33202 | integer *), dlarf_(char *, integer *, integer *, doublereal *, |
| 33203 | integer *, doublereal *, doublereal *, integer *, doublereal *), xerbla_(char *, integer *); |
| 33204 | |
| 33205 | |
| 33206 | /* |
| 33207 | -- LAPACK routine (version 3.2) -- |
| 33208 | -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| 33209 | -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| 33210 | November 2006 |
| 33211 | |
| 33212 | |
| 33213 | Purpose |
| 33214 | ======= |
| 33215 | |
| 33216 | DORG2R generates an m by n real matrix Q with orthonormal columns, |
| 33217 | which is defined as the first n columns of a product of k elementary |
| 33218 | reflectors of order m |
| 33219 | |
| 33220 | Q = H(1) H(2) . . . H(k) |
| 33221 | |
| 33222 | as returned by DGEQRF. |
| 33223 | |
| 33224 | Arguments |
| 33225 | ========= |
| 33226 | |
| 33227 | M (input) INTEGER |
| 33228 | The number of rows of the matrix Q. M >= 0. |
| 33229 | |
| 33230 | N (input) INTEGER |
| 33231 | The number of columns of the matrix Q. M >= N >= 0. |
| 33232 | |
| 33233 | K (input) INTEGER |
| 33234 | The number of elementary reflectors whose product defines the |
| 33235 | matrix Q. N >= K >= 0. |
| 33236 | |
| 33237 | A (input/output) DOUBLE PRECISION array, dimension (LDA,N) |
| 33238 | On entry, the i-th column must contain the vector which |
| 33239 | defines the elementary reflector H(i), for i = 1,2,...,k, as |
| 33240 | returned by DGEQRF in the first k columns of its array |
| 33241 | argument A. |
| 33242 | On exit, the m-by-n matrix Q. |
| 33243 | |
| 33244 | LDA (input) INTEGER |
| 33245 | The first dimension of the array A. LDA >= max(1,M). |
| 33246 | |
| 33247 | TAU (input) DOUBLE PRECISION array, dimension (K) |
| 33248 | TAU(i) must contain the scalar factor of the elementary |
| 33249 | reflector H(i), as returned by DGEQRF. |