
CUPMTR(l) ) CUPMTR(l)
NAME
CUPMTR  overwrite the general complex MbyN matrix C with SIDE = 'L' SIDE = 'R' TRANS =
'N'
SYNOPSIS
SUBROUTINE CUPMTR( SIDE, UPLO, TRANS, M, N, AP, TAU, C, LDC, WORK, INFO )
CHARACTER SIDE, TRANS, UPLO
INTEGER INFO, LDC, M, N
COMPLEX AP( * ), C( LDC, * ), TAU( * ), WORK( * )
PURPOSE
CUPMTR overwrites the general complex MbyN 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 nq1 elementary reflectors, as returned by CHP
TRD using packed storage:
if UPLO = 'U', Q = H(nq1) . . . H(2) H(1);
if UPLO = 'L', Q = H(1) H(2) . . . H(nq1).
ARGUMENTS
SIDE (input) CHARACTER*1
= 'L': apply Q or Q**H from the Left;
= 'R': apply Q or Q**H from the Right.
UPLO (input) 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 (input) CHARACTER*1
= 'N': No transpose, apply Q;
= 'C': Conjugate transpose, apply Q**H.
M (input) INTEGER
The number of rows of the matrix C. M >= 0.
N (input) INTEGER
The number of columns of the matrix C. N >= 0.
AP (input) 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 (input) COMPLEX array, dimension (M1) if SIDE = 'L'
or (N1) if SIDE = 'R' TAU(i) must contain the scalar factor of the elementary
reflector H(i), as returned by CHPTRD.
C (input/output) COMPLEX array, dimension (LDC,N)
On entry, the MbyN matrix C. On exit, C is overwritten by Q*C or Q**H*C or
C*Q**H or C*Q.
LDC (input) INTEGER
The leading dimension of the array C. LDC >= max(1,M).
WORK (workspace) COMPLEX array, dimension
(N) if SIDE = 'L' (M) if SIDE = 'R'
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = i, the ith argument had an illegal value
LAPACK version 3.0 15 June 2000 CUPMTR(l) 
