1DLATZM(1)                LAPACK routine (version 3.1)                DLATZM(1)
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NAME

6       DLATZM - i deprecated and has been replaced by routine DORMRZ
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SYNOPSIS

9       SUBROUTINE DLATZM( SIDE, M, N, V, INCV, TAU, C1, C2, LDC, WORK )
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11           CHARACTER      SIDE
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13           INTEGER        INCV, LDC, M, N
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15           DOUBLE         PRECISION TAU
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17           DOUBLE         PRECISION  C1( LDC, * ), C2( LDC, * ), V( * ), WORK(
18                          * )
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PURPOSE

21       This routine is deprecated and has been replaced by routine DORMRZ.
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23       DLATZM applies a Householder matrix generated by DTZRQF to a matrix.
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25       Let P = I - tau*u*u',   u = ( 1 ),
26                                   ( v )
27       where v is an (m-1) vector if SIDE = 'L', or a (n-1) vector if  SIDE  =
28       'R'.
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30       If SIDE equals 'L', let
31              C = [ C1 ] 1
32                  [ C2 ] m-1
33                    n
34       Then C is overwritten by P*C.
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36       If SIDE equals 'R', let
37              C = [ C1, C2 ] m
38                     1  n-1
39       Then C is overwritten by C*P.
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ARGUMENTS

43       SIDE    (input) CHARACTER*1
44               = 'L': form P * C
45               = 'R': form C * P
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47       M       (input) INTEGER
48               The number of rows of the matrix C.
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50       N       (input) INTEGER
51               The number of columns of the matrix C.
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53       V       (input) DOUBLE PRECISION array, dimension
54               (1  +  (M-1)*abs(INCV))  if SIDE = 'L' (1 + (N-1)*abs(INCV)) if
55               SIDE = 'R' The vector v in the representation of P.  V  is  not
56               used if TAU = 0.
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58       INCV    (input) INTEGER
59               The increment between elements of v. INCV <> 0
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61       TAU     (input) DOUBLE PRECISION
62               The value tau in the representation of P.
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64       C1      (input/output) DOUBLE PRECISION array, dimension
65               (LDC,N)  if  SIDE  = 'L' (M,1)   if SIDE = 'R' On entry, the n-
66               vector C1 if SIDE = 'L', or the m-vector C1 if SIDE = 'R'.
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68               On exit, the first row of P*C if SIDE = 'L', or the first  col‐
69               umn of C*P if SIDE = 'R'.
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71       C2      (input/output) DOUBLE PRECISION array, dimension
72               (LDC, N)   if SIDE = 'L' (LDC, N-1) if SIDE = 'R' On entry, the
73               (m - 1) x n matrix C2 if SIDE = 'L', or the m x (n - 1)  matrix
74               C2 if SIDE = 'R'.
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76               On  exit,  rows 2:m of P*C if SIDE = 'L', or columns 2:m of C*P
77               if SIDE = 'R'.
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79       LDC     (input) INTEGER
80               The leading dimension of the arrays C1 and C2. LDC >= (1,M).
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82       WORK    (workspace) DOUBLE PRECISION array, dimension
83               (N) if SIDE = 'L' (M) if SIDE = 'R'
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87 LAPACK routine (version 3.1)    November 2006                       DLATZM(1)
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