LAPACK 3.12.0
LAPACK: Linear Algebra PACKage
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◆ cunmr3()

subroutine cunmr3 ( character side,
character trans,
integer m,
integer n,
integer k,
integer l,
complex, dimension( lda, * ) a,
integer lda,
complex, dimension( * ) tau,
complex, dimension( ldc, * ) c,
integer ldc,
complex, dimension( * ) work,
integer info )

CUNMR3 multiplies a general matrix by the unitary matrix from a RZ factorization determined by ctzrzf (unblocked algorithm).

Download CUNMR3 + dependencies [TGZ] [ZIP] [TXT]

Purpose:
!>
!> CUNMR3 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(1) H(2) . . . H(k)
!>
!> as returned by CTZRZF. Q is of order m if SIDE = 'L' and of order n
!> if SIDE = 'R'.
!> 
Parameters
[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]L
!>          L is INTEGER
!>          The number of columns of the matrix A containing
!>          the meaningful part of the Householder reflectors.
!>          If SIDE = 'L', M >= L >= 0, if SIDE = 'R', N >= L >= 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
!>          CTZRZF in the last 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 CTZRZF.
!> 
[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
!> 
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Contributors:
A. Petitet, Computer Science Dept., Univ. of Tenn., Knoxville, USA
Further Details:
!>