
SORMR2(l) ) SORMR2(l)
NAME
SORMR2  overwrite the general real m by n matrix C with Q * C if SIDE = 'L' and TRANS =
'N', or Q'* C if SIDE = 'L' and TRANS = 'T', or C * Q if SIDE = 'R' and TRANS = 'N', or
C * Q' if SIDE = 'R' and TRANS = 'T',
SYNOPSIS
SUBROUTINE SORMR2( SIDE, TRANS, M, N, K, A, LDA, TAU, C, LDC, WORK, INFO )
CHARACTER SIDE, TRANS
INTEGER INFO, K, LDA, LDC, M, N
REAL A( LDA, * ), C( LDC, * ), TAU( * ), WORK( * )
PURPOSE
SORMR2 overwrites the general real m by n matrix C with Q * C if SIDE = 'L' and TRANS =
'N', or Q'* C if SIDE = 'L' and TRANS = 'T', or C * Q if SIDE = 'R' and TRANS = 'N', or C
* Q' if SIDE = 'R' and TRANS = 'T', where Q is a real orthogonal matrix defined as the
product of k elementary reflectors
Q = H(1) H(2) . . . H(k)
as returned by SGERQF. Q is of order m if SIDE = 'L' and of order n if SIDE = 'R'.
ARGUMENTS
SIDE (input) CHARACTER*1
= 'L': apply Q or Q' from the Left
= 'R': apply Q or Q' from the Right
TRANS (input) CHARACTER*1
= 'N': apply Q (No transpose)
= 'T': apply Q' (Transpose)
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.
K (input) INTEGER
The number of elementary reflectors whose product defines the matrix Q. If SIDE =
'L', M >= K >= 0; if SIDE = 'R', N >= K >= 0.
A (input) REAL array, dimension
(LDA,M) if SIDE = 'L', (LDA,N) if SIDE = 'R' The ith row must contain the vector
which defines the elementary reflector H(i), for i = 1,2,...,k, as returned by
SGERQF in the last k rows of its array argument A. A is modified by the routine
but restored on exit.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,K).
TAU (input) REAL array, dimension (K)
TAU(i) must contain the scalar factor of the elementary reflector H(i), as
returned by SGERQF.
C (input/output) REAL array, dimension (LDC,N)
On entry, the m by n matrix C. On exit, C is overwritten by Q*C or Q'*C or C*Q'
or C*Q.
LDC (input) INTEGER
The leading dimension of the array C. LDC >= max(1,M).
WORK (workspace) REAL 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 SORMR2(l) 
