Subroutine */
| 2314 | } /* cgehrd_ */ |
| 2315 | |
| 2316 | /* Subroutine */ int cgelq2_(integer *m, integer *n, complex *a, integer *lda, |
| 2317 | complex *tau, complex *work, integer *info) |
| 2318 | { |
| 2319 | /* System generated locals */ |
| 2320 | integer a_dim1, a_offset, i__1, i__2, i__3; |
| 2321 | |
| 2322 | /* Local variables */ |
| 2323 | static integer i__, k; |
| 2324 | static complex alpha; |
| 2325 | extern /* Subroutine */ int clarf_(char *, integer *, integer *, complex * |
| 2326 | , integer *, complex *, complex *, integer *, complex *), |
| 2327 | clarfg_(integer *, complex *, complex *, integer *, complex *), |
| 2328 | clacgv_(integer *, complex *, integer *), xerbla_(char *, integer |
| 2329 | *); |
| 2330 | |
| 2331 | |
| 2332 | /* |
| 2333 | -- LAPACK routine (version 3.2.2) -- |
| 2334 | -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| 2335 | -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| 2336 | June 2010 |
| 2337 | |
| 2338 | |
| 2339 | Purpose |
| 2340 | ======= |
| 2341 | |
| 2342 | CGELQ2 computes an LQ factorization of a complex m by n matrix A: |
| 2343 | A = L * Q. |
| 2344 | |
| 2345 | Arguments |
| 2346 | ========= |
| 2347 | |
| 2348 | M (input) INTEGER |
| 2349 | The number of rows of the matrix A. M >= 0. |
| 2350 | |
| 2351 | N (input) INTEGER |
| 2352 | The number of columns of the matrix A. N >= 0. |
| 2353 | |
| 2354 | A (input/output) COMPLEX array, dimension (LDA,N) |
| 2355 | On entry, the m by n matrix A. |
| 2356 | On exit, the elements on and below the diagonal of the array |
| 2357 | contain the m by min(m,n) lower trapezoidal matrix L (L is |
| 2358 | lower triangular if m <= n); the elements above the diagonal, |
| 2359 | with the array TAU, represent the unitary matrix Q as a |
| 2360 | product of elementary reflectors (see Further Details). |
| 2361 | |
| 2362 | LDA (input) INTEGER |
| 2363 | The leading dimension of the array A. LDA >= max(1,M). |
| 2364 | |
| 2365 | TAU (output) COMPLEX array, dimension (min(M,N)) |
| 2366 | The scalar factors of the elementary reflectors (see Further |
| 2367 | Details). |
| 2368 | |
| 2369 | WORK (workspace) COMPLEX array, dimension (M) |
| 2370 | |
| 2371 | INFO (output) INTEGER |
| 2372 | = 0: successful exit |
| 2373 | < 0: if INFO = -i, the i-th argument had an illegal value |