dlatzm(3F)

NAME
     DLATZM - applie a Householder matrix generated by DTZRQF to a matrix

SYNOPSIS
     SUBROUTINE DLATZM( SIDE, M, N, V, INCV, TAU, C1, C2, LDC, WORK )

         CHARACTER      SIDE

         INTEGER        INCV, LDC, M, N

         DOUBLE         PRECISION TAU

         DOUBLE         PRECISION C1( LDC, * ), C2( LDC, * ), V( * ), WORK( *
                        )

PURPOSE
     DLATZM applies a Householder matrix generated by DTZRQF to a matrix.

     Let P = I - tau*u*u',   u = ( 1 ),
                                 ( v )
     where v is an (m-1) vector if SIDE = 'L', or a (n-1) vector if SIDE =
     'R'.

     If SIDE equals 'L', let
            C = [ C1 ] 1
                [ C2 ] m-1
                  n
     Then C is overwritten by P*C.

     If SIDE equals 'R', let
            C = [ C1, C2 ] m
                   1  n-1
     Then C is overwritten by C*P.


ARGUMENTS
     SIDE    (input) CHARACTER*1
             = 'L': form P * C
             = 'R': form C * P

     M       (input) INTEGER
             The number of rows of the matrix C.

     N       (input) INTEGER
             The number of columns of the matrix C.

     V       (input) DOUBLE PRECISION array, dimension
             (1 + (M-1)*abs(INCV)) if SIDE = 'L' (1 + (N-1)*abs(INCV)) if SIDE
             = 'R' The vector v in the representation of P. V is not used if
             TAU = 0.
     INCV    (input) INTEGER
             The increment between elements of v. INCV <> 0

     TAU     (input) DOUBLE PRECISION
             The value tau in the representation of P.

     C1      (input/output) DOUBLE PRECISION array, dimension
             (LDC,N) if SIDE = 'L' (M,1)   if SIDE = 'R' On entry, the n-
             vector C1 if SIDE = 'L', or the m-vector C1 if SIDE = 'R'.

             On exit, the first row of P*C if SIDE = 'L', or the first column
             of C*P if SIDE = 'R'.

     C2      (input/output) DOUBLE PRECISION array, dimension
             (LDC, N)   if SIDE = 'L' (LDC, N-1) if SIDE = 'R' On entry, the
             (m - 1) x n matrix C2 if SIDE = 'L', or the m x (n - 1) matrix C2
             if SIDE = 'R'.

             On exit, rows 2:m of P*C if SIDE = 'L', or columns 2:m of C*P if
             SIDE = 'R'.

     LDC     (input) INTEGER
             The leading dimension of the arrays C1 and C2. LDC >= (1,M).

     WORK    (workspace) DOUBLE PRECISION array, dimension
             (N) if SIDE = 'L' (M) if SIDE = 'R'