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LAPACK
3.7.0
LAPACK: Linear Algebra PACKage
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subroutine cunml2 | ( | character | SIDE, |
character | TRANS, | ||
integer | M, | ||
integer | N, | ||
integer | K, | ||
complex, dimension( lda, * ) | A, | ||
integer | LDA, | ||
complex, dimension( * ) | TAU, | ||
complex, dimension( ldc, * ) | C, | ||
integer | LDC, | ||
complex, dimension( * ) | WORK, | ||
integer | INFO | ||
) |
CUNML2 multiplies a general matrix by the unitary matrix from a LQ factorization determined by cgelqf (unblocked algorithm).
Download CUNML2 + dependencies [TGZ] [ZIP] [TXT]
CUNML2 overwrites the general complex m-by-n matrix C with Q * C if SIDE = 'L' and TRANS = 'N', or Q**H* C if SIDE = 'L' and TRANS = 'C', or C * Q if SIDE = 'R' and TRANS = 'N', or C * Q**H if SIDE = 'R' and TRANS = 'C', where Q is a complex unitary matrix defined as the product of k elementary reflectors Q = H(k)**H . . . H(2)**H H(1)**H as returned by CGELQF. Q is of order m if SIDE = 'L' and of order n if SIDE = 'R'.
[in] | SIDE | SIDE is CHARACTER*1 = 'L': apply Q or Q**H from the Left = 'R': apply Q or Q**H from the Right |
[in] | TRANS | TRANS is CHARACTER*1 = 'N': apply Q (No transpose) = 'C': apply Q**H (Conjugate transpose) |
[in] | M | M is INTEGER The number of rows of the matrix C. M >= 0. |
[in] | N | N is INTEGER The number of columns of the matrix C. N >= 0. |
[in] | K | K is INTEGER The number of elementary reflectors whose product defines the matrix Q. If SIDE = 'L', M >= K >= 0; if SIDE = 'R', N >= K >= 0. |
[in] | A | A is COMPLEX array, dimension (LDA,M) if SIDE = 'L', (LDA,N) if SIDE = 'R' The i-th row must contain the vector which defines the elementary reflector H(i), for i = 1,2,...,k, as returned by CGELQF in the first k rows of its array argument A. A is modified by the routine but restored on exit. |
[in] | LDA | LDA is INTEGER The leading dimension of the array A. LDA >= max(1,K). |
[in] | TAU | TAU is COMPLEX array, dimension (K) TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by CGELQF. |
[in,out] | C | C is COMPLEX array, dimension (LDC,N) On entry, the m-by-n matrix C. On exit, C is overwritten by Q*C or Q**H*C or C*Q**H or C*Q. |
[in] | LDC | LDC is INTEGER The leading dimension of the array C. LDC >= max(1,M). |
[out] | WORK | WORK is COMPLEX array, dimension (N) if SIDE = 'L', (M) if SIDE = 'R' |
[out] | INFO | INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value |
Definition at line 161 of file cunml2.f.