LAPACK
3.4.2
LAPACK: Linear Algebra PACKage
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Go to the source code of this file.
Functions/Subroutines | |
subroutine | dlatzm (SIDE, M, N, V, INCV, TAU, C1, C2, LDC, WORK) |
DLATZM |
subroutine dlatzm | ( | character | SIDE, |
integer | M, | ||
integer | N, | ||
double precision, dimension( * ) | V, | ||
integer | INCV, | ||
double precision | TAU, | ||
double precision, dimension( ldc, * ) | C1, | ||
double precision, dimension( ldc, * ) | C2, | ||
integer | LDC, | ||
double precision, dimension( * ) | WORK | ||
) |
DLATZM
Download DLATZM + dependencies [TGZ] [ZIP] [TXT]This routine is deprecated and has been replaced by routine DORMRZ. DLATZM applies a Householder matrix generated by DTZRQF to a matrix. Let P = I - tau*u*u**T, 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.
[in] | SIDE | SIDE is CHARACTER*1 = 'L': form P * C = 'R': form C * P |
[in] | M | M is INTEGER The number of rows of the matrix C. |
[in] | N | N is INTEGER The number of columns of the matrix C. |
[in] | V | V is 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. |
[in] | INCV | INCV is INTEGER The increment between elements of v. INCV <> 0 |
[in] | TAU | TAU is DOUBLE PRECISION The value tau in the representation of P. |
[in,out] | C1 | C1 is 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'. |
[in,out] | C2 | C2 is 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'. |
[in] | LDC | LDC is INTEGER The leading dimension of the arrays C1 and C2. LDC >= (1,M). |
[out] | WORK | WORK is DOUBLE PRECISION array, dimension (N) if SIDE = 'L' (M) if SIDE = 'R' |
Definition at line 152 of file dlatzm.f.