cupmtr.f man page

cupmtr.f —

Synopsis

Functions/Subroutines

subroutine cupmtr (SIDE, UPLO, TRANS, M, N, AP, TAU, C, LDC, WORK, INFO)
CUPMTR

Function/Subroutine Documentation

subroutine cupmtr (characterSIDE, characterUPLO, characterTRANS, integerM, integerN, complex, dimension( * )AP, complex, dimension( * )TAU, complex, dimension( ldc, * )C, integerLDC, complex, dimension( * )WORK, integerINFO)

CUPMTR

Purpose:

CUPMTR overwrites the general complex M-by-N matrix C with

                SIDE = 'L'     SIDE = 'R'
TRANS = 'N':      Q * C          C * Q
TRANS = 'C':      Q**H * C       C * Q**H

where Q is a complex unitary matrix of order nq, with nq = m if
SIDE = 'L' and nq = n if SIDE = 'R'. Q is defined as the product of
nq-1 elementary reflectors, as returned by CHPTRD using packed
storage:

if UPLO = 'U', Q = H(nq-1) . . . H(2) H(1);

if UPLO = 'L', Q = H(1) H(2) . . . H(nq-1).

Parameters:

SIDE

SIDE is CHARACTER*1
= 'L': apply Q or Q**H from the Left;
= 'R': apply Q or Q**H from the Right.

UPLO

UPLO is CHARACTER*1
= 'U': Upper triangular packed storage used in previous
       call to CHPTRD;
= 'L': Lower triangular packed storage used in previous
       call to CHPTRD.

TRANS

TRANS is CHARACTER*1
= 'N':  No transpose, apply Q;
= 'C':  Conjugate transpose, apply Q**H.

M

M is INTEGER
The number of rows of the matrix C. M >= 0.

N

N is INTEGER
The number of columns of the matrix C. N >= 0.

AP

AP is COMPLEX array, dimension
                     (M*(M+1)/2) if SIDE = 'L'
                     (N*(N+1)/2) if SIDE = 'R'
The vectors which define the elementary reflectors, as
returned by CHPTRD.  AP is modified by the routine but
restored on exit.

TAU

TAU is COMPLEX array, dimension (M-1) if SIDE = 'L'
                           or (N-1) if SIDE = 'R'
TAU(i) must contain the scalar factor of the elementary
reflector H(i), as returned by CHPTRD.

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.

LDC

LDC is INTEGER
The leading dimension of the array C. LDC >= max(1,M).

WORK

WORK is COMPLEX array, dimension
                         (N) if SIDE = 'L'
                         (M) if SIDE = 'R'

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.

Date:

November 2011

Definition at line 150 of file cupmtr.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

cupmtr(3) is an alias of cupmtr.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK