zlarf.f man page

zlarf.f —

Synopsis

Functions/Subroutines

subroutine zlarf (SIDE, M, N, V, INCV, TAU, C, LDC, WORK)
ZLARF applies an elementary reflector to a general rectangular matrix.

Function/Subroutine Documentation

subroutine zlarf (characterSIDE, integerM, integerN, complex*16, dimension( * )V, integerINCV, complex*16TAU, complex*16, dimension( ldc, * )C, integerLDC, complex*16, dimension( * )WORK)

ZLARF applies an elementary reflector to a general rectangular matrix.

Purpose:

ZLARF applies a complex elementary reflector H to a complex M-by-N
matrix C, from either the left or the right. H is represented in the
form

      H = I - tau * v * v**H

where tau is a complex scalar and v is a complex vector.

If tau = 0, then H is taken to be the unit matrix.

To apply H**H, supply conjg(tau) instead
tau.

Parameters:

SIDE

SIDE is CHARACTER*1
= 'L': form  H * C
= 'R': form  C * H

M

M is INTEGER
The number of rows of the matrix C.

N

N is INTEGER
The number of columns of the matrix C.

V

V is COMPLEX*16 array, dimension
           (1 + (M-1)*abs(INCV)) if SIDE = 'L'
        or (1 + (N-1)*abs(INCV)) if SIDE = 'R'
The vector v in the representation of H. V is not used if
TAU = 0.

INCV

INCV is INTEGER
The increment between elements of v. INCV <> 0.

TAU

TAU is COMPLEX*16
The value tau in the representation of H.

C

C is COMPLEX*16 array, dimension (LDC,N)
On entry, the M-by-N matrix C.
On exit, C is overwritten by the matrix H * C if SIDE = 'L',
or C * H if SIDE = 'R'.

LDC

LDC is INTEGER
The leading dimension of the array C. LDC >= max(1,M).

WORK

WORK is COMPLEX*16 array, dimension
               (N) if SIDE = 'L'
            or (M) if SIDE = 'R'

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

September 2012

Definition at line 129 of file zlarf.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

zlarf(3) is an alias of zlarf.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK