clarf.f

Section: LAPACK (3)
Updated: Tue Nov 14 2017
Page Index
 

NAME

clarf.f  

SYNOPSIS


 

Functions/Subroutines


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

Function/Subroutine Documentation

 

subroutine clarf (character SIDE, integer M, integer N, complex, dimension( * ) V, integer INCV, complex TAU, complex, dimension( ldc, * ) C, integer LDC, complex, dimension( * ) WORK)

CLARF applies an elementary reflector to a general rectangular matrix.

Purpose:

 CLARF 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 (the conjugate transpose of 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 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
          The value tau in the representation of H.


C

          C is COMPLEX 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 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:

December 2016

Definition at line 130 of file clarf.f.  

Author

Generated automatically by Doxygen for LAPACK from the source code.


 

Index

NAME
SYNOPSIS
Functions/Subroutines
Function/Subroutine Documentation
subroutine clarf (character SIDE, integer M, integer N, complex, dimension( * ) V, integer INCV, complex TAU, complex, dimension( ldc, * ) C, integer LDC, complex, dimension( * ) WORK)
Author